# 8x30 Milling Machine Restoration



## Radials (Oct 29, 2018)

After over a year of this project the finish line is slowly creeping into sight and I've decided it's time to put together my pictures and notes from the rebuild of this milling machine to post out to the forum. Admittedly a rebuild like this wouldn't take nearly this long had I been able to focus full time on it but life only allows so much some times. In any case I'm pleased with how it has developed, and I'll now attempt to catch this posting up as quickly as possible to where things actually are in the rebuild process. 

Let's go back to the beginning...

I had been on the lookout for a milling machine for a garage machine shop for a while. A knee style mill was most desirable to me and I had narrowed my search down to the Taiwanese 8x30 mill. Grizzly seemed to be the only company still importing these but paying over $4K for just the mill wasn't going to happen which put me into the used market. After about 5 months of looking one showed up on eBay that seemed like a good candidate. It was listed by a machinery seller in the greater LA area so shipping up to Oregon wouldn't be too bad. The machine was listed as a 20 to 30 year old house branded floor model that has never been used. Essentially new, but in need of a rebuild from sitting so long. I made them an offer which was declined, so I made a higher one which was my limit and they also declined that. A month and a half later the machine is still listed so I made yet another offer just a shade above my first low offer and they accepted. On the truck it went up here to Oregon. 




Here's the mill right after I pulled it off the truck. It certainly looked like its sat around for a long time but with no signs of ever being used. They stated that the handles were removed at one point and sold to another customer so there was an obviously long period of time that the machine wasn't even being cranked based on the oil staining marks from where the saddle and knee have been situated. 







A coworker helped me get the machine home and unloaded. The engine hoist (crucial!!) worked great but was at it's travel limits lifting it off the trailer so some scooting and swinging was needed to get it all the way. 





After getting the mill on the floor the route forward was to fully disassemble it for a thorough cleaning and paint job after fixing all the chips in the fairing compound.


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## Radials (Oct 29, 2018)

An engine hoist in a small shop is a necessity in my opinion. I have moved this machine 3 or 4 times along with lifting all the heavy sub components and it's still proven to be the best money I've spent in the shop thus far. It's also what makes doing all this solo even possible. 

The teardown was pretty straight forward. I downloaded the Grizzly G0730 manual for a parts and assembly reference. The Grizzly model is identical to this mill. It's since been discontinued however but the G0731 is still available except comes with a factory x-axis power feed. 





All the oil on the machine had turned into a varnish. Nothing slid but the sliding surfaces looked great. I used lots of penetrating oil to get things 
to start moving.



Thick layer of fuzz dust on the knee bevel gears.







Thick chunk of (old grease?) blocking off one of the knee oil feeds. I'm not even sure how this would have gotten in there but good to find. 



The spindle was seized and the grease on top was clumpy. In fact all the grease in the machine is clumpy. While the upper bearing (visible in picture) was trash the spindle bearings did clean up beautifully. Had I put power to the machine right from the get go they would have been trashed as well. Along with the upper head bearings which also cleaned up great.


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## Radials (Oct 30, 2018)

During the course of the tear down I came across a number of disappointments that are probably to be expected in the import machine arena. The ones I could do something about I would.



Take note of the two set screws on the top surface of the x-axis saddle dovetail. That's where the guy at the factory missed the drill hole to the oil passage below twice and plugged the holes with the screws. Third times a charm....



The motor did not swing much at all and in general the design of the belt tensioner wasn't very effective. Take note of the concentricity of the pin holes on the lower tabs of the motor mount. This I was going to do something about. More on that later.




A lot of cleaning and prep work was done and I simply went with Rust-Oleum smoke gray for everything. I ended up rolling the paint on the base with a 4" paint roller and it came out looking much better than I had expected.








Finally it was nice to get to the point of some reassembly.



All the bearings in the knee assembly cleaned up fine with the exception for one on the crank handle shaft that was replaced.


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## Radials (Oct 30, 2018)

The current Grizzly variant has crank wheels on it and I'm partial to crank handles. I also sourced these from Grizzle and only had to broach a new keyway in them and add the setscrew. The knee handle fit perfect as did the dial which took almost two months on back order. Again, all the bearings that could be cleaned and repacked were or else replaced as nothing spun freely.






Now its starting to look like something.



The lube oilier was scrubbed and received new o-rings and gaskets.



All new oil lines throughout. The pump oilier was reinstalled on some standoffs so that it would clear the future y-axis DRO scale.



The table sliding back on. The bracket sitting on top of the mill will become the DRO and power switch mount down the road.


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## Radials (Oct 30, 2018)

Tackling the motor mount.

The current factory job wasn't going to do so I came up with a new one. First I took the portion of the motor mount that connects to the mill and machined the preexisting tabs off of them and faced the cast surface flat. The tab that stuck off of the side was also machined off. I'll note that I'm fortunate enough to work at a machine shop where I'm permitted to come in on the weekends and use the machines for personal use. That has been a much appreciated privilege and made many steps along the way possible. 

The new motor mount is made from 3/8" mild steel plate and barrel hinges so that the motor could easily be lifted on and off the machine when needed. 






The new mill side of the motor mount is bolted over the top of the old one which is now faced and flat. A Carr-Lane push pull toggle clamp acts as the belt tensioning mechanism.









Here's the finished motor mount with the cleaned up and painted motor installed. Worth mentioning that the motor is the only component I haven't opened up. It actually spins very nice so we'll see how it does once it gets put to work for the first time in 2+ decades. 




The carriage bolt in the end of the toggle clamp will provide a small amount of adjustment if needed in the belt tensioning.


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## Grandpop (Oct 30, 2018)

I have the exact same machine. Mine is a MSC brand, and the castings are identical. Mine is probably a little older, as I do not have a one shot lube on mine. It had the ball oilers, but they did not cover several sliding surfaces.

 Like you, I took mine apart to clean and improve it a bit. I added some oil retention scrape marks, added lube lines every sliding surface plus the table nuts and vertical bevel gears. Drilled and tapped the ball oilers for grease fittings and made 2 oil guns to lube it. I added 2 adjustable lock levers from McMaster to the table locks, 1 to the cross lock, and 1 to the knee lock. Much better than the stock locks. Also made some brass tips were the locks push against the gibs.

I like your motor mount. Mine is still mostly stock. I bored the off center holes in correct location (mine were not as bad as yours), added bushings to correct them. I still use the original tensioner. Never had the belt slip.

I did not find the RPM convenient so I moved my motor pulley up so top pulley groove in line with top pulley on intermediate pulley block. That gives a better choice of speeds in the 350-1100 range that I use most. I milled the slot widths in the base of the intermediate block to make them a slip fit for diameter of headed bushings, and milled the thickness so the head of the bushings are a couple thousandth slip fit. Tighten the bolts one time and have never touched them since. Just loosen the tensioner in the back and any belt change can be made by just sliding the intermediate block by hand. Very easy and recommended.

Watching to see rest of your mods.


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## Radials (Oct 30, 2018)

Grandpop said:


> It had the ball oilers, but they did not cover several sliding surfaces.



Something I thought was interesting was the internal oiling system does not deliver oil to the sliding surface of the knee gib. It actually oils the back side of the gib which isn't any help. I didn't correct this issue and sitting here thinking about it now but likely drilling the gib and adding some oil grooves to it would have been beneficial. I just made a mental note that I'll be manually putting some oil on the gib side dovetail.



Grandpop said:


> I added 2 adjustable lock levers from McMaster to the table locks, 1 to the cross lock, and 1 to the knee lock. Much better than the stock locks. Also made some brass tips were the locks push against the gibs.



I elected to install my x-axis DRO scale on the front of the table to not loose the Y travel when having it installed on the back of the table. In doing this I lost both the table travel limit stops and direct access to the threaded holes on the saddle that the table locks go into. The locks I can still make work but I'm thinking I'll be making some sort of locking handle with a jog in it to clear the DRO scale. The table stops will also still be possible in another way that I just haven't thought of or seen an example of yet. Installing the Y-axis DRO scale also made me remove the table stops strip originally located there as well. More details yet to be sorted out.

Thanks for the input on the pulley group mod. I'm going to keep that in mind once I see how I like the available speeds. I've got a motor and VFD on the shelf that I was tempted to put on this rebuild but I'm thinking I want to use it on something else.


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## Radials (Oct 30, 2018)

The original power switch is not located in a good location in my opinion. I'd prefer to have my hand up high and clear of the cutting area if I ever had to go for the switch in a hurry rather than reaching around the side next to the cutting tool. As mentioned there is a bracket I'm making (made) that will hold both the DRO head mount and the power switch up high on the machine which took care of this problem. The second problem was the large hole in the side of the casting where the old power switch used to be.

If you look back to the very first picture you'll see that the attached machine operator light was ripped out and resting on the knee. The threads in the casting were pretty bad and rather than trying to repair them I plugged the hole and painted over it. Figuring that somehow the future switch/ DRO arm would also have the light mounted to it. Instead of going that route I came up with another idea to swap the light to the opposite side of the mill and make a mount that would plug the original switch hole at the same time.




I welded together this bracket arm that bolts from the inside and clamps down on the casting.



The light cleaned up nicely and threads into the top of the arm, and the wiring is still routed inside the casting. There was some waviness between the surface of the column and my plate which created small gaps in places. I had some roll rubber on hand so I cut a 1/8" thick gasket to sandwich between the two surfaces to take up the gap and keep chips from collecting here. Probably a non issue once the way cover goes on and shields this area as well.


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## Grandpop (Oct 31, 2018)

I am in FL right now attending my rapidly failing father, but will send some photos when I get home Friday.

Mine did not have a factory light, but I did bolt one on the left side of casting. I also have a DRO from the PO, and the scale is on the front. That is why I needed the adjustable handle locks, as wasn't enough room under the scale to unlock and lock them. I can tell that on mine I keep the gib slightly loose, but you do need both locks tight when cutting with side of end mill.

PO never mounted the DRO head display so I made a pivoting arm base that mounts about where your light is.

Yes. I did drill thru the knee gib to get oil to the other side and added long oil grooves too.

I did not mention it, but this is my only mill. In order to mill the middle pulley base I bought a long belt that goes from motor to spindle pulley. This also provides added speed ranges even when the middle pulley is installed, I use it often.

I have designed a 3 piece riser system that will incorporate a long sliding dovetail block between upper / lower spacers so the head can be moved behind the table all the way out past front of table. Have the steel bought but have not made a chip yet. Hopefully will be my winter project. Kind of like putting a suit on a pig, but the size of the mill fits my available space perfectly.


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## Radials (Oct 31, 2018)

Grandpop said:


> I am in FL right now attending my rapidly failing father, but will send some photos when I get home Friday.
> 
> Mine did not have a factory light, but I did bolt one on the left side of casting. I also have a DRO from the PO, and the scale is on the front. That is why I needed the adjustable handle locks, as wasn't enough room under the scale to unlock and lock them. I can tell that on mine I keep the gib slightly loose, but you do need both locks tight when cutting with side of end mill.
> 
> ...



I'm very interested to see what you've done and what you've got in mind for that head sliding setup! I have been rolling around the idea of making a riser too that would incorporate a way to adjust the head nod without having to shim.    

Best of luck to you and your family with your father.

Nick


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## Grandpop (Nov 2, 2018)

Nick,
Thanks for the thoughts of my father. This site is welcome distraction right now!

Not sure where to start, so in no particular order, here is my mill today.



Some of the changes I made, some of which are mentioned above. First is the added oil lines to the lead and elevation screws (you can see the oil scrape marks I put back on. Yes I know that isn't the right way, but it way better than none). I just drilled thru the screw to get to the elevation gears/screw. Yours would need metering valves added if you did the same.



My machine did not have way wipers for the knee, so I drilled and tapped these holes for future wipers, then made and installed them with as much felt as possible.





Machine did have a front way wiper cover (no felt underneath of it), but did not have a rear way wiper cover. I had to remill the front one to allow for the felt, and made this rear wiper cover.




My motor mount pivot holes were bad, but not as bad as yours. This is how the mount drooped when I got it with all of the slop in it, and the pivot holes after the bushings were installed.





More to follow,
Ted


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## Grandpop (Nov 2, 2018)

part 2....

My machine now has 110 volt light, readout, and power feed, but there was never a place to plug everything in. I added this box to the back and split the incoming 220 to the 110 inside.



My original table, knee and cross locks were crap, and did not have any brass tips where they pushed on the gibs. You see the nice adjustable handles in the DRO photos.




And speaking of the DRO, this is how mine mounts, with plenty of room for the new adjustable handles. Not a great scale like one I would have bought, but I rarely use it so works for me. I did pop in 37 holes on ~3" bolt circle once for an indexer, so was VERY glad I had one.








PO never mounted the read out, I guess it set it somewhere? This is how I mounted the read out. Welded bracket with plastic bushings on machine, bent bracket on read out, plastic bushing at read out, the tube has large 45s on the read out end with welded caps at both ends. Slide to position easily and stays there.








When I finally put my machine back together and started to use it, the first thing I found out is none of my new collets and end mill holders would fit inside the spindle (machine came with 1 collet installed). Thought it was the set screw so adjusted that, but turned out the bore at top of the spindle was too small by .0015, and PO had reduced the end of the collet to allow for it (maybe even his whole set). I asked my Dad (another former tool and die maker) for advise, and he suggested making a sort of lap with crocus paper wrapped around the end. I did not have much hope, but had nothing to lose, so made this, hooked it to my drill and went at it. Wore out 4 strips of crocus, but took less than an hour to have every last collet and end mill holder fit as they should. ALWAYS listen to your elders!






another interesting thing I discovered when I bought a hold down kit was the T nuts would not fit the table. Required tee nuts 9/16 x 7/8 x 11/32 heads can be had easily on web, but my table needed the 11/32 heads slightly thinner (.330 max), some of the 9/16 width reduced (my slots are more like .560 and slightly tapered with .559 at bottom), and if the 7/8 was not exactly centered to the 9/16, then I had to reduce the 7/8 a bit. This is what I had at the time. At time I did not have a surface grinder (mill was first purchase), so had to mill them as best I could with carbide end mill (you can the shinny surfaces). Funny, but since I now have dozens more (I mostly use the 3/8 thread stuff today, not the 1/2 in the photo) I just dusted all of the ones I now have the other day on my current surface grinder (way easier).



slide and pulley block to follow...


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## Grandpop (Nov 2, 2018)

part 3 ....
This is how I made changing the speeds quick and easy. Original design has the intermediate pulley block bolted fast, so needed to loosen the motor adjuster, then the 2 bolts, move the belts, then tighten the motor adjuster and then the 2 bolts. First improvement I made was to mill the intermediate pulley block slot widths to slight slip fit with oil/bronze bushings, then cleaned up the top surfaces so they were same thickness each side and length. I stated in previous post they were headed bushings, but forgot that didn't work so I took the heads off and just used thick washers I filed flat. The intermediate pulley block now just slides back and forth with light hand pressure, never have had need to touch those bolts again. Belt changes less than a minute (with most of that looking at the belt speed chart figuring where I need to put the belts).






Also raised the motor pulley up to match the top spindle/intermediate block pulley heights. This allows for more usable speed range than the machine came with. Motor pulley used to come loose every so often (single set screw on top of the key) even when thread locker was used, so I added 2 other tapped holes and now have 3 set screws equally spaced around the diameter (matching flats filled to motor shaft). They have not come loose since I did that.




How much more usable you ask. First is what I started with, and 2nd is where I am today. I gained aprox new 350, 600, 700, 800 & 1000, but lost the max 3440 that I would never use anyway. The red speeds are when you take a single long belt direct from motor to the spindle and bypass the middle pulley. I was going to make a new motor pulley with 4 grooves for even more spreed ranges, but this is working well for me so may never do that.






and finally my future head riser with slide adjustment. This will be 5" thick, and made from 3 main blocks. Bottom and top will be round to match the mill, but will have dovetails cut into them. A fixed long block with matching dovetails will slide in/out between each upper/lower block. Does not to be super tight precision on the dovetails; I will simply lock the long slider with screws with brass tips pushing against it. As I purchased the steel, this will provide some 14" front/back adjustment. I am not really interested in a nod feature, as my machine is .0015 out on a 8" diameter circle front/back, and better side/side. Plus once shimmed you can easily mark it and you are done (and I now have the surface grinder for things that need to be perfect). This was a simple mock-up I made from wood to double check what I drew on the computer. The final slider block will be longer (only limited by motor mount and rear of spindle casting), but same principal. First photo would be basically as machine is today, 2nd would be head out past table, and 3rd would head back behind table.







The little steel block above sitting on the prototype was just used to stop the part from tipping over during the photos. It is actually one of a set of 4 (exactly 1, 2, 3 and 4" long) that I made years ago for Bridgeports and fits this machine - I use them to lock the spindle down when milling so quill can't move.

Last is the progress to date on the slide - supplies delivered. I found a deal on ebay one time and bought the 8" dia 4140 blocks thicker than I needed for $80 each delivered. Funny but they came USPS in a priority mail box at about 76 lbs ea for $15 shipping - just barely fit in there (my mailman was glad I was home that day to unload them from the truck). The 8" dia blocks need to be cut about 1.5" (or faced) to length. They did not originally fit into my 4x6 cut off saw, so would have had to face them off. I have since modified that saw so they will fit between the guides (barely) today by adding a new location for the fixed jaw. Will still be limited to 5" height of saw casting restriction, but can cut them from both sides in the saw so won't have to face them off for hours and will have some usable scrap peices.



Need to make an indexable dovetail cutter (best) and worst case I buy one from Shars. Going to be many hours into this one....

Ted


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## Grandpop (Nov 2, 2018)

Nick,
I forgot to ask how did you get the spindle out? My spindle makes noise and I need to get some new bearings in there.

Ted


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## Radials (Nov 2, 2018)

Grandpop said:


> Nick,
> I forgot to ask how did you get the spindle out? My spindle makes noise and I need to get some new bearings in there.
> 
> Ted



Ted,

Very complete write up and thanks. I'm going to work my way backwards through them with some more comments but for starters here's the spindle removal information. 

All of the items shown in the red rectangles will need to come off to drop the spindle out. Essentially the pinion train on the quill as the rack teeth on the spindle body don't go all the way to the top, and the return spring needs to be released. The actual pinion gear shaft comes out the right side but in order to free it up you'll need to remove the fine feed engagement components on the left side of the head. The fine feed handle assembly can stay in place I believe. You'll need to remove the depth stop screw to get access to the screws that hold the block (#121) onto the spindle. Perhaps take that piece off last so you have something to keep the spindle from dropping out while futzing with the pinion assembly. 



I made a simple pin wrench tool to crack the spindle nose cap open. I'm not sure what method yours will be, but that seems like a common way the caps are secured. I didn't have any bearing drivers that worked for reassembly so I turned up a set to include one for the head. 




As I was putting my head assembly back together I was a little puzzled as to why the spindle lock hangs out so far in front of the head? Looking at pictures on grizzly's site the current model is still done this way. I took a stab at guessing this isn't actually necessary for any reason (I hope ) and shortened mine up before final reassembly. The actuation was dialed in so that the spindle lock is fully loose at 12:00 and fully tightened by 7:00. The spreader spring had to be replaced in doing this but it seems like it works just fine. 




I went ahead and drilled and tapped the head assembly and the spindle stop block for the future quill DRO while everything was disassembled. 




This is as far as the spindle quill DRO install has gotten thus far. I got the idea for this from Dman1114 on this forum and his thread on installing a DRO on his Grizzly mill just like ours. 

https://www.hobby-machinist.com/threads/dro-install-grizzly-g1008-knee-mill.40480/

The laser cut steel brackets have yet to be drilled for the reader scale to be mounted on and I believe I'll need to make a secondary block as well to get the heights just right. Mine however is just the Shars caliper style quill DRO and not the remote display style as Dman1114 has. The spindle lock  handle swings in nicely behind the lower bracket.




And just because we're on the spindle/ head subject here's a look at the head assembly components....


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## Radials (Nov 2, 2018)

Ted,

One more thing about that spindle...

Before you remove the nose cap take note if there is any gap between the cap and spindle body. I didn't on mine because I didn't even think to look. On reassembly the cap sat quite away further from the spindle body than I would have thought (around .05 if I recall right). Since the bottom portion of the threaded cap is pressing against the spindle bearings themselves I figured perhaps the bearings weren't actually fully seated all the way down in the spindle. I disassembled the spindle to measure up the component stacks and sure enough a gap was inevitable. The edge of the cap that contacts the bearings was faced down so that it was bottomed out about the time the gap closed up. Had I known ahead of time the gap wouldn't have raised the alarm that the bearings might not be seated, but I'm happy I did it anyway.

Nick


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## Radials (Nov 2, 2018)

Ted,

Yes I can see where that pulley block would be a problem. Glad you've got it right in the sweet spot now. Our mill design diverge here a little as mine has a pulley mounted on a swing arm. I'm hoping that the factory got the parallelism close on this to the spindle pulley as I'm not sure how I would correct it if it's off. I'd probably have to shim the pulley sub plate to align it. 




Your mill had a little wider speed range, at least initially, then mine does. It seems that the speeds I have match what the current Griz model does, but I'm going to check it with the tach once its up and running. I like the idea of gaining the extra speed options going with a single belt. One of the other items I made for the machine is a whole new belt cover which I did for a few reasons. First is that the original case aluminum belt cover is big and weighs 20 pounds without all the fairing compound on it. My machine came with the cover broken off the hinges as you can see in the above picture they are damaged. There was some deep cracks and chips to the compound on the cover so I decided to blast it all off and redo it. The compound was thick! The center of the casting looked like a ski jump that the factory tried to even out with the compound about 3/16" thick across parts of the top. With the casting blasted down to bare metal I only started to re-skim it before giving up on that idea in favor of making a new one. 




Here's a look at the cover blasted down to the bare casting. 

Second in addition to the weight of the cover I liked the idea of being able to have quick access to the draw bar like on many other styles of mills. Often I find myself changing tools without always needing to change speeds. Third is that I'm thinking at some point I want to add either a spindle lock or spindle brake and needed some way to mount that. And as if those all weren't good enough reasons the new motor mount I made pushed the motor back far enough that it bumps the old cover, so it looks like I was sold on the idea. 

Here's what I came up with for that.




The new cover is all welded 3/16" steel. Not lighter than the original aluminum one but only the access door needs to be opened to change the belts. The height is much lower than the stock cover and the top of the spindle pulley isn't too far below the opening which provides easy access to the draw bar. At some point if I decide to make a spindle brake/ lock I've also got a good solid structure to mount it too, and would likely locate it on top of the cover. The cover will be mounted down to the pulley sub plate casting to keep it secure. 



Side access door flips open. 

Now admittedly I made a gaffe in the design of this cover. It sits too low to actually remove a belt off the top of the pulley without having to take the bolts out and lifting the cover up. (Whoops) Belt changes will still work fine but in the rare occasions that a belt needs to be replaced the whole cover comes off. With you mentioning running single belt I see that I'm probably not going to be able to do that. 

You're ram riser assembly looks like an awesome project. I suppose if you wanted to ovoid the dovetail cutter you could make a fixture to hold the part at your given angle to mill the bevels with a straight end mill. However making the cutter also sounds like a fun project. 



Grandpop said:


> The little steel block above sitting on the prototype was just used to stop the part from tipping over during the photos. It is actually one of a set of 4 (exactly 1, 2, 3 and 4" long) that I made years ago for Bridgeports and fits this machine - I use them to lock the spindle down when milling so quill can't move.



Could you please explain how these work? Do they sit around the limit screw on the head? 

Nick


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## Grandpop (Nov 3, 2018)

Nick,
 thanks for the spindle write up. I definitely have to look into that. 

I like how you do the quote thing. It took me awhile, but I think I finally figured that quote thing out, so here goes.



Radials said:


> I made a simple pin wrench tool to crack the spindle nose cap open. I'm not sure what method yours will be, but that seems like a common way the caps are secured. I didn't have any bearing drivers that worked for reassembly so I turned up a set to include one for the head.



MY lower cap does have holes for a pin wrench. like you I just drilled holes into end of a long bar. I had to take that end cap off to get to the collet set screw.



Radials said:


> Yes I can see where that pulley block would be a problem. Glad you've got it right in the sweet spot now. Our mill design diverge here a little as mine has a pulley mounted on a swing arm. I'm hoping that the factory got the parallelism close on this to the spindle pulley as I'm not sure how I would correct it if it's off. I'd probably have to shim the pulley sub plate to align it.



If you run into problems you could always just make a base like mine, it can't ever tilt that way. I have that same pivoting setup on my 2 drill presses. One of them never worked right, so I did add a plate and 2 holes like I did for the mill. Works great there as well.



Radials said:


> Now admittedly I made a gaffe in the design of this cover. It sits too low to actually remove a belt off the top of the pulley without having to take the bolts out and lifting the cover up. (Whoops) Belt changes will still work fine but in the rare occasions that a belt needs to be replaced the whole cover comes off. With you mentioning running single belt I see that I'm probably not going to be able to do that.



 I find that I often just change the collet without changing speeds, so you would be good for those changes. When I do change speeds, it seems like every time I have to take at least one belt off to change the one on top. Same thing on the drill presses, always taking one belt off. I find that I need plenty of space for my hands to take the belt off. Could you just make a riser and weld that onto base of your new cover?

By the way, your welds are MUCH nicer than mine! Wish I could do that as nice.



Radials said:


> At some point if I decide to make a spindle brake/ lock I've also got a good solid structure to mount it too, and would likely locate it on top of the cover.



 I thought I was going to want a brake/lock as well after all the time on Bridgeports with them. Never had a need for a lock on this mill - it is very easy just to hold the spindle pulley with one hand while loosening / tightening the drawbar. Occasionally I do miss the brake, but it is rare. Somewhere I have a design squirreled away where a guy put a pad underneath the spindle pulley with a side mounted lever. It looked slick and is also on m,y someday list of things to do.

And speaking of future things to do, I have only rarely ever wanted a quill DRO in my 30 + machine years (either on mill or lathe tailstock). I have lots of images I have saved of how others did their DRO brackets for the quill, but yours look very nice. Interested to see how that finishes up. 

Few times it happened that I needed real depth control with the quill I just rigged an indicator. Mostly when I need an exact depth on the mill I lock the quill and use the knee screw. My mill actually came with a really bad home made quill indicator holder, one that limited the quill travel to less than 1". First thing I threw away. 



Radials said:


> I suppose if you wanted to avoid the dovetail cutter you could make a fixture to hold the part at your given angle to mill the bevels with a straight end mill.



I have a 3 way tilting 5" vise, so using the bottom of a cutter was the plan for the dovetails on the side of the sliding plate. The dovetails on the bottom and top blocks I would use the home made or bought cutter.



Grandpop said:


> The little steel block above sitting on the prototype was just used to stop the part from tipping over during the photos. It is actually one of a set of 4 (exactly 1, 2, 3 and 4" long) that I made years ago for Bridgeports and fits this machine - I use them to lock the spindle down when milling so quill can't move.





Radials said:


> Could you please explain how these work? Do they sit around the limit screw on the head?



I lower the quill to where I want it, then put the blocks on top of the quill travel blocks, raise the quill back up trapping the blocks, then lightly tightened to stop against bottom of the quill travel block.  Maybe these photos will explain it better than I can with words.  Here is the 2" block installed



Here is the 2 and 1" blocks installed


Blocks are simply 1.5 dia cold rolled steel with a .530 wide slot milled thru them.
	

		
			
		

		
	





When using end mills I almost exclusively use end mill holders over collets. The end mill set screw chamfer is down against the side of the set screw as well when tightened. I have seen way too many things ruined over the years due to end mill slippage within collets or quill slippage when it isn't rigidly locked (folks think the quill lock will hold it in place) that I just avoid that possibility whenever I can. Even with the end mill holders I also lock the quill with the stop blocks. I always use the knee screw for final sizing. Only time I use a collet with an end mill is when I am trying to maintain an exact diameter or not cutting accurately on the bottom.

To hold size on a part with the Bridgeports (and works well in my 8 x 30) I always locked the quill at top to start, and I usually started with 1" parallels under part in the vise. All of my milling parallels are exactly on fractional inch size, and in .125 increments. Once you got the size you were looking for on the part, I set the dial on the knee to that actual number i just measured. After that you can mill blocks all day long and know exactly where you are by the knee dial without using micrometers every 2 minutes. Reason for the exact 1, 2, 3 and 4" stop blocks was so I did not have to reset the knee dial when I needed more quill travel - I was still accurate with the knee dial when the quill moved down 2 inches. Saved many hours every week with that method. Still needed mics, but not every 2 minutes.

I use indexable cutters as much as possible to keep my end mill costs down. My favorite ones are the 1" negative rake series (like the Valenite mini-mill 45° chamfer one in photo above). The negative ones always want to push back up into the quill (which can only make the part bigger than intended if that happens), so I will use these with collets. When I use the positive indexable cutters they want to pull down so they always go into the end mill holders. My big flycutter for finishing cuts bolts on an arbor so that can't pull down either. I am probably overly anal about that, but then again I have rarely wrecked a block due to being too small.

Ted


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## Radials (Nov 3, 2018)

Ted,



Grandpop said:


> If you run into problems you could always just make a base like mine, it can't ever tilt that way. I have that same pivoting setup on my 2 drill presses. One of them never worked right, so I did add a plate and 2 holes like I did for the mill. Works great there as well.



As you can see I keep all options open lol. That might be the case too, and another option I'll consider if its the one out of the three that can't be aligned.



Grandpop said:


> I find that I often just change the collet without changing speeds, so you would be good for those changes. When I do change speeds, it seems like every time I have to take at least one belt off to change the one on top. Same thing on the drill presses, always taking one belt off. I find that I need plenty of space for my hands to take the belt off. Could you just make a riser and weld that onto base of your new cover?
> 
> By the way, your welds are MUCH nicer than mine! Wish I could do that as nice.



It looks like I'll still be able to get one belt above the other or vice versa by swapping ends off the top of the center pulley out the access door. Your riser idea might happen if things are still a no go. When I make it out to the garage today I'll double check that. You know what they say about not succeeding the first time...

I would have preferred to mig weld this cover as I'm a little better doing that but it didn't work out to use the welding shop at work. I ended up stick welding it at home because thats what I've got. It turned out not looking too bad after it was all dressed up. 



Grandpop said:


> And speaking of future things to do, I have only rarely ever wanted a quill DRO in my 30 + machine years (either on mill or lathe tailstock). I have lots of images I have saved of how others did their DRO brackets for the quill, but yours look very nice. Interested to see how that finishes up.



I didn't do the quill DRO thinking I really needed it. I was at the moment with all the parts for the mill head disassembled and thought to myself that now is the time to put the threaded holes in them if I wanted to do so. This portion of the build isn't a huge priority but will just be a nice option to have. I had all the parts for the belt cover I made laser cut and figured I'd toss a few brackets in on the order while I was at it for the quill DRO.



Grandpop said:


> I have a 3 way tilting 5" vise, so using the bottom of a cutter was the plan for the dovetails on the side of the sliding plate. The dovetails on the bottom and top blocks I would use the home made or bought cutter.



Right! I was overly focused on the slide and not on the blocks. How will you gain access to the bolts on the head assemble to rotate it? Are you planning on pocketing out the sides of the blocks for those? 

I really like your quill travel block set you made. That's not something I've come across yet and see how its a very simple effective solution to the problem. I'm going to borrow that one from you at some point. 

Nick


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## Silverbullet (Nov 4, 2018)

Nice job on your mill, I have the enco copy hopefully ill get it restored to use . It had been used only for drilling before I got it . They said the motor was shot ,, only needed a new capacitor ,, $12.00 USA not China $4.00.  I didn't like the small cranks so I ordered 6" cast iron chromed to replace those. If I'm able I do plan on stripping and repaint and bearings also. Dro cheap set to start never had a machine with cheaters on it. Hopping and praying these back problems heal up or go away. Thank you God


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## Radials (Nov 4, 2018)

Silverbullet said:


> Nice job on your mill, I have the enco copy hopefully ill get it restored to use . It had been used only for drilling before I got it . They said the motor was shot ,, only needed a new capacitor ,, $12.00 USA not China $4.00.  I didn't like the small cranks so I ordered 6" cast iron chromed to replace those. If I'm able I do plan on stripping and repaint and bearings also. Dro cheap set to start never had a machine with cheaters on it. Hopping and praying these back problems heal up or go away. Thank you God



Thank you, the job has been glacial but I'm getting down the mountain. 

I'm really hoping that you get past those back problems and back out in the shop. In due time though please don't rush it. Hopefully something on this thread is helpfully to you during your rebuild and if you have any questions don't hesitate to ask. 

Nick


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## AndySomogyi (Dec 3, 2018)

Nice mill! 

Hey, would you by any chance have diameters on your pulleys? 

I just bought the variable speed version of this mill, and I'd like to fabricate a set of pulleys so that I get proper mechanical gear reduction in addition to the variable frequency drive.


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## Radials (Dec 5, 2018)

AndySomogyi said:


> Nice mill!
> 
> Hey, would you by any chance have diameters on your pulleys?
> 
> I just bought the variable speed version of this mill, and I'd like to fabricate a set of pulleys so that I get proper mechanical gear reduction in addition to the variable frequency drive.



Thank you.

Here's what my mill has for pulley sizes....

There is no info plate on the motor, but since all the speeds are near identical to the current Griz G0731 I believe it to be a 1.5hp 1725 rpm motor. 

Nick


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## AndySomogyi (Dec 6, 2018)

Wow, thanks!!! Much appreciated!

Mine is the variable speed version of the same mill, and my motor, at 60 hz is 1.5 hp, 1725 RPM.

I just have a single pulley set that just about corresponds to the 3rd highest speed with the step pulley.

Hence, it works fine at higher rpm, but bogs down at lower rpm without the true torque increase you get with step pulleys.

It’s a real nice machine, these 8x30s. I’ve used a real Bridgeport previously, and I just sold a crappy round column mill. The round column mill was an exercise in frustration and just felt like a toy. But this 8x30 mill feels just like a real full-size Bridgeport only smaller. It’s very nice to use.



Radials said:


> Thank you.
> 
> Here's what my mill has for pulley sizes....
> 
> ...






Sent from my iPhone using Tapatalk Pro


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## Radials (Dec 6, 2018)

AndySomogyi said:


> Wow, thanks!!! Much appreciated!
> 
> Mine is the variable speed version of the same mill, and my motor, at 60 hz is 1.5 hp, 1725 RPM.
> 
> ...



Sure thing. If you end up making those pulleys make sure to post some pictures. I'd love to see what you come up with.


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## Paul Jr (Jan 15, 2019)

Excellent Info Radials! I just got an Enco model from 1985 over this past weekend. It's in pretty good shape aside from it never having oil points or grooves installed. I am in the process of trying to figure out the best placement points for my fittings, specifically for the table ways. Does the oil make it to the opposite side of the ways from the fittings installed on the end? I want to place them there for convenience but my feeling is they will not adequately provide lubrication. I also would like to ensure lube gets to the gib and dovetail surfaces. Can you provide some insight to how yours have been working so far, photos of your fitting placement would be fantastic! Thanks for the helpful info thus far!


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## Radials (Jan 26, 2019)

Hello Paul and congratulations on the new-to-you machine! 

My machine progress has really slowed down. As mentioned in the more recent posts I had there was a problem with belt clearance that I failed to realize before fabricating the new belt cover. I have since corrected this but haven't spent much time on this project beyond that partly because of how cold its been here. Now I'm in the process of prepping my current house to rent out and scheming how I'm going to get the milling machine up the very steep driveway of the new house I'm moving into in the coming months. That might require disassembling it again to make it more manageable which kinda makes me glad that the oilier system on my mill still currently is dry. If I do that I'll also correct some things I wish I would have done before assembling it which would include a couple new oil ports perhaps.

Yes, oil is intended to pump into the fitting on the end of the saddle and splits off to the different dovetails of the table as shown below. The center fitting position is where the oil comes up from the knee and ties into this block. 




Here are a few view the oil takes to get to the top sides of the dovetails from there.






Oil line turns up and goes though the saddle casting to deliver oil to the top side of the rear dovetail.

Sitting looking through my pictures I'm just not recalling how the oil makes it's way to the gib face along with the opposing dovetail face... I know in the case of the knee the oil is delivered to the back side of the gib which makes no sense. I believe however that in my assessment of the oilier system my mill has I just accepted the fact that the one shot would get oil to many places but some manually applied oil would also be necessary as well. The holes that can be seen in the saddle casting breaking through horizontally to the dovetail in the front are for the saddle locks and in the rear are the drill thru holes for the rear way covers. So i'm not thinking there is any oil delivery to the dovetail. 

If/when this machine comes apart again I believe I'll drill and tap some manual oil points as Ted has shown above on his mill. 

By the way sorry for the long wait on the reply. Just as mentioned life has stacked up on me over the last few months. Take some pictures and feel free to add them here on what you decide to do with your oil system. 

Nick


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## AndySomogyi (Jan 26, 2019)

I’ve got the Taiwan made, Grizzly branded same 8x30 mill.

Got the head trimmed to 5/10’ths tram side to side.

But it’s out about 1.5 thousands in the Y (nod) direction. Guess I’ll have to eventually pull the head off and scrape the pivot surface.

How tight do you guys adjust the knee gibs in z direction on these?








Sent from my iPad using Tapatalk Pro


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## Radials (Jan 30, 2019)

AndySomogyi said:


> How tight do you guys adjust the knee gibs in z direction on these?
> 
> Sent from my iPad using Tapatalk Pro



I'm not sure what to suggest on making the knee gib adjustment. When I was reassembling my machine I only had the knee on the machine and kept tightening it until there was no rock in the knee and no noticeable drag when lowering it. 

Nick


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## Pfowler67 (May 17, 2020)

Hello all! 
I'm a brand new member, so bear with me.
Stumbled across this forum a while back - so much helpful information. 

I've been looking for one of these 8x30 knee mills for some time, posted an ad on Craigslist (looking to buy) and recently received a nice email from a guy just down the road in Vancouver, who is selling his 'pristine' KBC branded machine. So I went to see it yesterday and it really is awesome! He wants $2500 CAD for it so i'm really excited to be going to collect it on wednesday. Check out the pics and see what you all think. All the ways are beautifully clean and the spindle is like new. All very smooth and tight throughout.
My next challenge will be to dismantle it, drive it home to Whistler and lug it down the 15 steps at the front of my place, through three 30" doorways and into my shop. Wish me luck!


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## Silverbullet (May 17, 2020)

Pfowler67 said:


> Hello all!
> I'm a brand new member, so bear with me.
> Stumbled across this forum a while back - so much helpful information.
> 
> ...


If it dont work out theres one on craigslist in south jersey but it needs work cleaning n restoring- says needs capacitor for motor. But its $1,000 enco Taiwan made.


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## Giorgio (May 17, 2020)

Hey Pfowler,

The machine looks good. Some tooling and the vice would be nice to come with it. Hope it does. 

I picked up the Craftex (BusyBee) version of this mill a few years back here in New Westminster. I’m still new to milling, but have no problem smoking the odd endmill and milling bigger pieces of steel into smaller pieces! Im not too excited by belt changes and need to sort that out with some kind of mod for my machine.

I MUST add a DRO. 

Best of luck lugging that monster down to the basement.  I hired a HIAB and we wheeled into the garage.


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## Aaron_W (May 17, 2020)

Pfowler67 said:


> Hello all!
> I'm a brand new member, so bear with me.
> Stumbled across this forum a while back - so much helpful information.
> 
> ...




These mills look like they are heavily inspired by the Clausing 8520. I was able to disassemble my Clausing into 5 major components, head, motor, table, column/knee and stand which made moving it very easy. I was able to hand carry everything (most parts 50-100lbs) except the column / knee (200-300lbs) which required two people to load in my truck, and I unloaded / moved into my shop with an engine hoist and a sturdy cart. If I had removed the knee I probably could have done the whole thing by hand by myself.

One major difference is the Clausing sits on a steel box / stand which can be separated from the column. It looks like this mill extended the column casting to form a base, which will make moving the column more difficult (heavier). I was able to hand carry the column on my Clausing with 2 people, knee intact. If you remove the knee you could probably do the same. I'd recommend using a small movers cart as it sounds like you may have a bit of a walk from the driveway to your shop.


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## Radials (May 18, 2020)

Pfowler67 said:


> Hello all!
> I'm a brand new member, so bear with me.
> Stumbled across this forum a while back - so much helpful information.
> 
> ...



Hi there and welcome! Looks worth the price to me as I've been very happy with my machine. Dismantling the machine isn't bad with the help of an engine hoist. I thought I was moving awhile back and designed a sled I could put just the base of the machine on laying on its back so that it could be moved in the bed of my truck. The idea was that only a engine hoist would be needed to move it. I'm happy I didn't have to but think the idea would have worked out well enough. Post some pictures of the move and good luck!

Nick


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## BGHansen (May 18, 2020)

+1 on Radials disassembly of the machine.  I have a Jet JVM-830, same mill.  I pulled the motor, then the turret.  I slid the rest (base, column, knee and table) down a board into my basement.  I think I used a come-along to control it down the board, but don't recall for sure as it was 35 years ago.  I got it out of the basement by pulling the turret/motor and used a skid trolley and a 12V truck winch to lift it out.  Pulled the turret/motor with an engine hoist.

Bruce


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## Radials (May 18, 2020)

Giorgio said:


> Im not too excited by belt changes and need to sort that out with some kind of mod for my machine.



I wasn't happy with the belt tensioning method either on the machine, you can see earlier in this post how bad my machine motor mount was from the factory. I came up with this mod to easily get the tension just right. The toggle does most of the work and the threaded carriage bolt in the end of it allows the tension to be dialed in just right with a few spins. I did have to make a new belt cover as well when I did this because it pushed the motor back far enough to contact the old cover. It just sits on the shelf now if anyone is in need of one. 

I assure the critiquing masses that the belts matching the toggle clamps was completely fortuitous. Not that I'm not the type that would do such a thing, but in this case I went to Napa looking for belts and lo and behold I snag a few style points out of luck.


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## Pfowler67 (Jun 1, 2020)

Hey all, 
Well, it's in the shop ok, still in pieces, but it's in!

Took the heavy beast apart into four pieces; column/base, head, table and knee - all came apart very easily to my relief. Rented a 4foot mechanical 'Genie' fork lift to lift the column and base into the van, then out again and onto a wooden sled I made to get it down the steps. The steps here are wooden sleepers set into the hill at the front of our place. Thankfully, the sled had enough friction on the steps to prevent a total toboggan-like disaster, so we could quite easily slide it without any worry at all. Phew! Then we used the lift again at the bottom to dolly the machine inside and through all the doorways. It now rests in the four pieces in my shop while I source some nice way oil and am able to spend a bit of time cleaning and reassembling. Then I'll get round to installing a 3axis DRO. I will leave the machine in its single phase state for now I think, then maybe one day I will think about a VFD. No plans yet though. 

I'm so happy I found this machine. It really does seem to have not been used very much at all. A very lucky find indeed.


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## Pfowler67 (Jun 1, 2020)

Oh, forgot to mention, its a Taiwan made machine, made in 1994. I like some of the mods you guys have made to your machines and will be thinking about those when I rebuild mine.

Cheers!


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## AndySomogyi (Oct 4, 2020)

Hey @Radials, how did you take the knee off? 

I’m trying to fix my Grizzly and looks like there are two ball bearings that hold the knee to the screw, so they have to be pressed out?


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## Radials (Oct 4, 2020)

AndySomogyi said:


> Hey @Radials, how did you take the knee off?
> 
> I’m trying to fix my Grizzly and looks like there are two ball bearings that hold the knee to the screw, so they have to be pressed out?



Yes there are two bearings on the knee lead screw. I removed my knee by rotating the head out of the way and cranked the knee up as high as it would go. With an engine hoist attached I loosened the knee gib and then hoisted the knee off the dovetail with the screw still attached. This method worked but the knee wasn't balanced and was finicky to handle once in the air. My picture below indicate I changed the sling method at one point during removal. 



When I put it back on I made a block to mount to the center of the knee dovetail and got the balance right before lifting the knee up in the air so it was easier to guide back onto the base. 



The bearings as I recall didn't need to be pressed out, but tapped out with a brass punch. There is a castle nut and (tabbed washer?) that hold the screw into the bearings that is easy to remove.




-Nick


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## AndySomogyi (Oct 4, 2020)

Thanks for the info.

I was thinking about just lifting it out by hand, looks like it probably only weighs about 100 lbs or so (I deadlift 300  ), but maybe a hoist is smarter, like the hook idea.

It almost looks like with the gib removed it might slide straight out.

I originally just planed on scraping the top ways on mine because they were damaged from previous owner, but I’ve now found out that the knee is tilted sideways by about 0.015 over 8”, no wonder I could never machine a square part with that knee. 

Got a thread of my disaster here:









						Grizzly G0678 8x30: Repair, Scraping and Alignment
					

to be honest so far I've been pretty impressed - the nod was out by a touch, so I sorted that out with a piece of 7-up can between the knuckle and the base, which put it within 0.01mm over the width of the table. All the sliding surfaces are in good condition, no gouges or ugly machining marks...




					www.hobby-machinist.com


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## Mtnmac (Oct 4, 2020)

I bought one a couple years ago.  Found it down the road at a estate sale, 400 bucks.  I put my DRO on the front of the table too.  I made extensions so the X axis table locks extend out beyond the scale cover.  It's been a good machine, but will get a VFD eventually and keep the ability to move the belt for low end torque.  This also will give me reverse spindle rotation... this machine has none.


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## Radials (Oct 6, 2020)

AndySomogyi said:


> Thanks for the info.
> 
> I was thinking about just lifting it out by hand, looks like it probably only weighs about 100 lbs or so (I deadlift 300  ), but maybe a hoist is smarter, like the hook idea.



I actually weighed my knee while it was out. Only 55 lbs.


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## AndySomogyi (Oct 6, 2020)

Radials said:


> I actually weighed my knee while it was out. Only 55 lbs.
> 
> View attachment 339616



Thanks Much.

I got mine out, I’m surprised at how light it is. The bearing to screw fit was a bit on the tight side, but I just screws the Z screw in and it came loose. 

Now I’m working on squaring it up. The dovetails are WAY off, like 0.015 over 8”, and top ways were ground with a 0.005 twist. I’m guessing the knee probably slipped when they were grinding it.


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## Radials (Nov 26, 2020)

Ok, finally got a power feed on my mill. A few more details to sort out but came out nicely. 

Here's the project thread.









						8x30 Power X-Axis Power Feed
					

I've had an 8x30 x-axis power feed modification on the back burner for quite sometime now and I'm getting close with the project being complete. A goal of this project was to also replace the leadscrew bearing blocks on either end and align the leadscrew which was not parallel to the table. The...




					www.hobby-machinist.com


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## Pfowler67 (Nov 26, 2020)

Hi everyone. Excited to see some further modifications to you mill there, Radials. I just received my Sino DRO so am keen to get into that next, but here’s some pictures after getting mine home and into place.


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## Pfowler67 (Nov 26, 2020)

I still have some dialling in to do before the DRO goes on, so will do that first. There are some other mods I’d like to make too. One concerns the x axis leadscrew arrangement. Seems to have been put together rather wonkily! Doesn’t seem right anyway. I’ll put some pics on here for you to see.
Keep up the great work, Radials and everyone else!


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## Radials (Nov 26, 2020)

Pfowler67 said:


> I still have some dialling in to do before the DRO goes on, so will do that first. There are some other mods I’d like to make too. One concerns the x axis leadscrew arrangement. Seems to have been put together rather wonkily! Doesn’t seem right anyway. I’ll put some pics on here for you to see.
> Keep up the great work, Radials and everyone else!



Yea, as mentioned on my X-Axis power feed mod thread I also had a wonky factory install job on mine. The time I spent laying out the new bearing blocks to correctly align the lead screw made a big different in the feel of the mill.


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## Pfowler67 (Dec 29, 2020)

Hi folk!

So I finally got around to getting the new mill up and running, dialling in the gibs and have almost completed the DRO install. Here's some pics of the work so far. I will do the Z axis scale tomorrow.

I'm really happy with how rigid and well the whole thing has gone together so far. The trickiest part so far being the X axis reader mount, which I have made a special bracket for. I chose to mount the X axis scale on the rear of the table, as I like to use the limit stops on the front of my current machine and have managed to keep the amount of lost Y axis travel down to a minimum. The new machine has way more travel than my old machine so i'm happy to live with this decision.

I will post details on the Z axis installation soon.


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## u50067 (Jan 5, 2022)

Radials said:


> Yes there are two bearings on the knee lead screw. I removed my knee by rotating the head out of the way and cranked the knee up as high as it would go. With an engine hoist attached I loosened the knee gib and then hoisted the knee off the dovetail with the screw still attached. This method worked but the knee wasn't balanced and was finicky to handle once in the air. My picture below indicate I changed the sling method at one point during removal.
> View attachment 339371
> View attachment 339372
> 
> ...


Am a new member.  I have a Jet JVM-830 mfg in 1978.  Have used it mostly for drilling holes on location.  Have found the knee to quill distance to be not quite enough a couple of times.  So am considering making a riser.  Would like to fab the rise before disassembling the mill for installation.  I need the female and male diameters of the interface between the head and column. Also the depth of the female diameter that the male diameter is inserted into


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## u50067 (Jan 5, 2022)

Grandpop said:


> part 3 ....
> This is how I made changing the speeds quick and easy. Original design has the intermediate pulley block bolted fast, so needed to loosen the motor adjuster, then the 2 bolts, move the belts, then tighten the motor adjuster and then the 2 bolts. First improvement I made was to mill the intermediate pulley block slot widths to slight slip fit with oil/bronze bushings, then cleaned up the top surfaces so they were same thickness each side and length. I stated in previous post they were headed bushings, but forgot that didn't work so I took the heads off and just used thick washers I filed flat. The intermediate pulley block now just slides back and forth with light hand pressure, never have had need to touch those bolts again. Belt changes less than a minute (with most of that looking at the belt speed chart figuring where I need to put the belts).
> 
> View attachment 278887
> ...


Do you have the dimensions of the male and female diameters of the interface between the head and column??  Am considering fabing a 5 inch riser.   Also need the depth of the female diameter and the diameter of the bolt hole circle.  I would like to fab the riser before disassembling the mill for installation of the riser.  Maybe someone else has this info.


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## BGHansen (Jan 5, 2022)

You'll like having a 5" riser.  I made one from a solid round 6" long and ended up with a touch over 5".  I don't have the dimensions as this mod was done 35 years ago.  I had a Grizzly round column mill and Atlas 12 x 36 lathe at the time.  I pulled the head and measured that diameter.  I recall the 3 clamping bolts being evenly spaced.  The lathe work to turn the shoulder/pocket were done on the Atlas.  The pockets for the lower bolt holes in the riser were done on the Grizzly round column.  

If you don't have two mills available, pull the head, take your measurement of the shoulder on the bottom of the head.  Turn to that dimension on the lathe minus maybe 0.010". 

Another mod done by the previous owner to me was the addition of another set of pulleys above the motor and center pulley.  As designed, the slowest speed was 280 RPMs.  The larger upper/middle pulley cut that nearly in half to 145 RPMs.  I fab'd up the cover since the stock one wouldn't fit with the taller pulley stack.  My mill's speed chart is below; checked at the spindle with a Jacquet RPM meter.

Bruce


Jet JVM-830 mill with a 5" solid steel riser block


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## Radials (Jan 6, 2022)

u50067 said:


> Do you have the dimensions of the male and female diameters of the interface between the head and column??  Am considering fabing a 5 inch riser.   Also need the depth of the female diameter and the diameter of the bolt hole circle.  I would like to fab the riser before disassembling the mill for installation of the riser.  Maybe someone else has this info.


A head riser was on my list of modifications to do to this mill. Unfortunately, the need and opportunity to upgrade to a larger mill has come along for me resulting in the sale of my 8x30 milling machine recently. With it to the new owner went all my notes on the machine including the ones about the head riser dimensions. Even with these milling machine being very similar I honestly wouldn't want to build something for it without actually measuring my own machine since there are subtle differences. While it is more work probably the best option is like what Bruce mentioned to lift the head off. On my machine the power originally ran through the column up to the motor. Not sure if yours does, or if there's enough slack inside to account for a head riser. You may need to disconnect the motor though to lift the head. 

Nick


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## u50067 (Jan 6, 2022)

BGHansen said:


> You'll like having a 5" riser.  I made one from a solid round 6" long and ended up with a touch over 5".  I don't have the dimensions as this mod was done 35 years ago.  I had a Grizzly round column mill and Atlas 12 x 36 lathe at the time.  I pulled the head and measured that diameter.  I recall the 3 clamping bolts being evenly spaced.  The lathe work to turn the shoulder/pocket were done on the Atlas.  The pockets for the lower bolt holes in the riser were done on the Grizzly round column.
> 
> If you don't have two mills available, pull the head, take your measurement of the shoulder on the bottom of the head.  Turn to that dimension on the lathe minus maybe 0.010".
> 
> ...


Thanks for your response and info.  If I can learn how to use my wife's smart phone I may post a picture of what I have to attempt to make the riser from.  Your rpm reduction reminded me of what I did with one of my drill presses.  I addesd a jack shaft pulley in the middle and later obtained a 825 RPM motor.  The arrangement reduced the spindle RPM to approx 135 RPM according to an online calculator.


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## u50067 (Jan 7, 2022)

u50067 said:


> Thanks for your response and info.  If I can learn how to use my wife's smart phone I may post a picture of what I have to attempt to make the riser from.  Your rpm reduction reminded me of what I did with one of my drill presses.  I addesd a jack shaft pulley in the middle and later obtained a 825 RPM motor.  The arrangement reduced the spindle RPM to approx 135 RPM according to an online calculator.


Here is what I have for the riser.  Got it at a local junk yard for perhaps 20 cents a pound.   It is 7-1/2 inches in diameter (near same as mill column) x 5 inches tall.  The flanges are 7/8 inch thick, and the center is 3 inch x 1/4 inch wall pipe.  Thinking of welding at least three 3/8 thick gussets between the two flanges and to the center pipe, and then let it sit in the barn for at least a year.  A friend told me I would have better success getting the two faces parallel if the second face was faced on a surface grinder or a mill.  Any suggestions???


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## Grandpop (Jan 7, 2022)

I hope you misread your rule for that pipe wall thickness? Would be best if that was more than 1/4 wall thickness, as all of the milling loads are cantilevered quite a bit with a 3" OD pipe diameter riser to react the forces (as opposed to a 7-8 diameter riser).

Welding in the 6 gussets will help with the small diameter riser and the minimal wall thickness. After welding them in, I do not see much advantage to letting it sit for a year before final machining. You have to machine the top/bottom flanges of your weldment to match your mill anyway.

Not sure what equipment you have to machine the steps in the flanges, but you pretty much have 2 choices: a. milling machine AND rotary table, or b. lathe. Either way, when you machine the first flange recess or boss, the entire surface will be square/flat, so when you turn it over to do the other flange end it should not be out by hardly anything to worry about.

I measured the flange diameters on mine when I had it all apart after I first bought the machine. My flange outer diameters are 7.800, and the inner locating/rotating flanges are 4.720 (your machine will be different). The lower casting on mine is recessed, with the upper casting flange boss sticking out .250. If yours is same construction, the lower flange on your riser would need to stick out and the upper end would need a spot-face/recess.

As Bruce said, a .010 extra clearance on those flange fits is not going to hurt anything.

My approach is going to be a bit different than a solid 5" riser. I will be 5" overall, but with a 2" high x 6" wide x 12" long double dovetailed bar in the middle. This allows for the head to be moved out/back to reach every part of the table/part. I know that will take some of my rigidity away, but hoping that will be minimal compared to the greatly added flexibility of the fore/aft Bridgport like movement. Might be hard to see/understand, but it will look like this. Loosen 2 locking handles on top and bottom of the dovetailed bar, and slide the head where you want it, tighten 4 locking handles and start machining. The pink part sticking out the right side is just a rod to help slide the dovetailed bar. To make the dovetail milling in the top/bottom riser sections easier, the riser top/bottom will be hex shaped at dovetail end and round where it attaches to the machine.


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## Mark Early (Mar 23, 2022)

Very nice write up on your extensive project!  I have an Enco mill that I bought new in 2001 that looks identical to your project mill.  I don't use it much anymore and was getting ready to sell it to a young man that is a millwright.  I went to set it up with an endmill and no matter which collet I use I can't seem to get the collet to pull in tight to the end mill.  I was wondering if you could share some additional info on the quill rebuild you did?  I notice that my collets are getting a little gouging on the keyway a couple inches from the top.  Could the spindle set screw have loosened up?  Do I need a new spindle?  Thanks for any advice you can offer.  
Mark Early


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## MikeInOr (Mar 23, 2022)

Mark Early said:


> Very nice write up on your extensive project!  I have an Enco mill that I bought new in 2001 that looks identical to your project mill.  I don't use it much anymore and was getting ready to sell it to a young man that is a millwright.  I went to set it up with an endmill and no matter which collet I use I can't seem to get the collet to pull in tight to the end mill.  I was wondering if you could share some additional info on the quill rebuild you did?  I notice that my collets are getting a little gouging on the keyway a couple inches from the top.  Could the spindle set screw have loosened up?  Do I need a new spindle?  Thanks for any advice you can offer.
> Mark Early



I would first take a look at the draw bar.  I doubt it is the problem but it is really easy to remove and check.

I would then put a camera/cell phone camera on the table and point it directly up the spindle and take a picture.  You will, of course, need something to light the inside of the spindle while taking a picture.  I think a good picture of the inside of the spindle will show you what you need to do next.


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## Mark Early (Mar 24, 2022)

MikeInOr said:


> I would first take a look at the draw bar.  I doubt it is the problem but it is really easy to remove and check.
> 
> I would then put a camera/cell phone camera on the table and point it directly up the spindle and take a picture.  You will, of course, need something to light the inside of the spindle while taking a picture.  I think a good picture of the inside of the spindle will show you what you need to do next.


I will give that a try, thanks.  Also, I received the instructions to take everything apart from Grizzly.  Enco doesn't really support this machine any more, but the Grizzly looks like the same machine with some improvements over the years.


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## Mark Early (Mar 24, 2022)

Hi Mike,
Here is a photo of the machine and a look up from the bottom.  My guess is the set screw in the spindle is protruding out too far?  What do you think?
Mark


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## Mark Early (Mar 24, 2022)

hmmm, didn't see the photos, trying again


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## Mark Early (Mar 24, 2022)

How do you remove the drawbar from the spindle, and do you have any photos of how you removed the bearings?  I'm just trying to see why my collets won't draw up the end mill tight.  I have the quill assembly out of the machine and the draw bar is captive by something.  It's a 2001 Enco 8 x 30 from MSC I bought new.   Thanks,   Mark Early


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## Radials (Mar 24, 2022)

I though at first it was the drawbar as well. It'll just pull right out if you lift it up, but yours is stuck? To me the setscrew looks correct in your picture. Just enough to keep the collet from spinning while tightening the drawbar. It does take two wrenches to tighten the drawbar on these mills since there no spindle brake. Are you using two? I'm not really too sure as to what is keeping yours in the spindle.  Can you actually see the end of the bar? There should be some threads visible unless something is threaded onto it? 

Nick


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## MikeInOr (Mar 25, 2022)

Yes, the drawbar just pulls out the top of my Husky 8x30 mill.  I assumed most 8x30 mills are similar.

Let me preface this by saying I am no expert but "I" would be tempted to try to gently clean up the inside of the spindle.  Maybe some steel wool or scotch bright.  Nice job on the picture by the way.  I will confess to not having looked up the center of any other spindles but the set screw doesn't look out of whack to me either.  The bottom of the draw bar looks unusually rough... almost like a previous owner might have broken off the bottom threads?  I would definitely recommend pulling the draw bar out and looking at it.  I would appreciate a picture if you do so.  What happens when you try to pull the draw bar straight up?  Does it catch on something?

Radials did a really nice rebuild on his 8x30 and as such is much more knowledgeable with them than I am.  After reading his response several times I believe he is implying that *a broken off top of a collet or other tooling might be on the bottom threaded portion of the draw bar which would explain both why you can't remove the draw bar and why you can't get anything tight*.  Now that I think about it this does make perfect sense!  If this is so your next question will be: How do I fix it?  For which I think that you may have to cut off the top of the draw bar then slant the mill head to the side so you can pull the draw bar out the bottom of the spindle once the top hex has been sawed off.

I know that replacement drawbars can be had for quite cheap on ebay if you end up needing to replace yours.

I am really just guessing here... I look forwards to seeing what others have to say on the subject.

*Edit:* Another thought, if the draw bar is stuck and there is something foreign screwed onto the bottom of the draw bar threads maybe you could put a rod of round stock up the spindle and lower the spindle or raise the knee so that it puts pressure on the foreign object to keep if from spinning while unscrewing the drawbar from the top counter clockwise?  Maybe even use an impact wrench to try to unscrew the draw bar with the rod applying tension on the foreign piece?

*Edit2:* A higher resolution picture of the inside of the spindle might make it easier to decern if there is something foreign screwed on to the bottom of the draw bar... if possible.

*Edit3:* The threads on the end of a R8 draw bar are 7/16" x 20tpi.  A 1/2" schedule 40 iron pipe has an ID of .625".  Using a 1/2" pipe up through the spindle instead of the rod described above might allow you to actually pinch the foreign object between the pipe and the inside of the spindle while leaving the draw bar free to unscrew.  I would still use the table and raise the knee to provide the upwards pressure on the pipe.  I think this is the approach I would try first if you confirm there is something stuck on the bottom of the draw bar.  Putting the pressure directly on the foreign object instead of the bottom of the draw bar should be much more effective in capturing the object and keep it from spinning while unscrewing the draw bar.


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## Mark Early (Mar 25, 2022)

Radials said:


> I though at first it was the drawbar as well. It'll just pull right out if you lift it up, but yours is stuck? To me the setscrew looks correct in your picture. Just enough to keep the collet from spinning while tightening the drawbar. It does take two wrenches to tighten the drawbar on these mills since there no spindle brake. Are you using two? I'm not really too sure as to what is keeping yours in the spindle.  Can you actually see the end of the bar? There should be some threads visible unless something is threaded onto it?
> 
> Nick


Hi Nick,
Thanks for the information.  I was able to pull everything apart yesterday.  I have the quill, spindle and drawbar assembly in a vise (gently & padded).  There is something that the drawbar is secured to above the top of where a collet sits.  I kept spraying and dripping liquid wrench on the spindle and drawbar being careful not to get any on the bearings.  After a while I noticed that the collets would seat a little more deep in the spindle.  I think the drawbar and spindle come out as an assemble when the bearings are pressed out.  I'm not sure I want to mess with that at this point.  What did you do with yours to get the bearings out and repack or replace?  I saw there were comments about using heat to expand the quill and special races turned to match the bearings.  I had a 12 ton press that I recently got rid of, so not an option for me.  I think I'll fiddle with the quill to see if it was just dirty, rusty and dusty from not using it for a couple of years.  Can't believe I've had the machine for over 20 years now.
Mark


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## Radials (Mar 26, 2022)

Mark Early said:


> Hi Nick,
> Thanks for the information.  I was able to pull everything apart yesterday.  I have the quill, spindle and drawbar assembly in a vise (gently & padded).  There is something that the drawbar is secured to above the top of where a collet sits.  I kept spraying and dripping liquid wrench on the spindle and drawbar being careful not to get any on the bearings.  After a while I noticed that the collets would seat a little more deep in the spindle.  I think the drawbar and spindle come out as an assemble when the bearings are pressed out.  I'm not sure I want to mess with that at this point.  What did you do with yours to get the bearings out and repack or replace?  I saw there were comments about using heat to expand the quill and special races turned to match the bearings.  I had a 12 ton press that I recently got rid of, so not an option for me.  I think I'll fiddle with the quill to see if it was just dirty, rusty and dusty from not using it for a couple of years.  Can't believe I've had the machine for over 20 years now.
> Mark



Mark,

So just to clarify, it seems there was a time you used this machine and there was no trouble with the collet installation? Honestly I don't believe pressing the spindle out of the quill is necessary. The drawbar is a wear component on mills and having to go through all this just to change it doesn't seem logical. When I had my quill apart I didn't notice anything indicating that there was suppose to be an internal retainer on the drawbar. Mike's suggestion to put pressure on whatever you see up in the spindle threaded onto the drawbar to thread it out seems like a good method. Maybe even going as far as supergluing a modified rubber washer or some sandpaper to the end of the pipe/tube if you need some more grip on it. 

Nick


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## Mark Early (Mar 26, 2022)

Radials said:


> Mark,
> 
> So just to clarify, it seems there was a time you used this machine and there was no trouble with the collet installation? Honestly I don't believe pressing the spindle out of the quill is necessary. The drawbar is a wear component on mills and having to go through all this just to change it doesn't seem logical. When I had my quill apart I didn't notice anything indicating that there was suppose to be an internal retainer on the drawbar. Mike's suggestion to put pressure on whatever you see up in the spindle threaded onto the drawbar to thread it out seems like a good method. Maybe even going as far as supergluing a modified rubber washer or some sandpaper to the end of the pipe/tube if you need some more grip on it.
> 
> Nick


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## Mark Early (Mar 26, 2022)

Hmm,  I will check through all my collets to see if any are missing something.  Thanks for all the comments!  Soaked it overnight with penetrating oil and tried tapping on it with a brass punch so as not to bugger up the bottom of the drawbar.  Doesn't seem to want to move.  Dennis at the MSC machine support in Atlanta seemed to think maybe it is a washer that got rusted onto the drawbar.  I'll try some other tricks to free things up.  Does anyone know of a place where I can have new bearing installed?  I sold my 12 ton press recently and probably would not want to tackle this job anyway.


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## Mark Early (Mar 26, 2022)

Radials said:


> Mark,
> 
> So just to clarify, it seems there was a time you used this machine and there was no trouble with the collet installation? Honestly I don't believe pressing the spindle out of the quill is necessary. The drawbar is a wear component on mills and having to go through all this just to change it doesn't seem logical. When I had my quill apart I didn't notice anything indicating that there was suppose to be an internal retainer on the drawbar. Mike's suggestion to put pressure on whatever you see up in the spindle threaded onto the drawbar to thread it out seems like a good method. Maybe even going as far as supergluing a modified rubber washer or some sandpaper to the end of the pipe/tube if you need some more grip on it.
> 
> Nick


Hi Nick,

I get the dummy of the year award, but thanks to all the comments I finally figured it out.  The last job I used the 3/4 inch collet while milling a weld bead off a large trailer hitch extender for my camper.  When I pulled the collet out I didn't notice that the insert on the top of the collet was still on the drawbar, ha!  Here is a photo of a 7/8 and 3/4 collet side by side.  The 3/4 collet insert is missing and must be the piece on the end of the drawbar.  I've been running bridgeports since I was 18 and am now 67 and I have never seen a collet do this.  I'll have to get creative and somehow get ahold of that insert and remove it.  All these enco collets will then go into the steel recycle bin at the dump.  Thanks again for the help!


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## Mark Early (Mar 26, 2022)

what kind of dolly are you using to move the machine on?  Looks like it must be pretty robust.


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## Radials (Mar 27, 2022)

Ok glad you were able to figure out the problem! 



Mark Early said:


> what kind of dolly are you using to move the machine on?  Looks like it must be pretty robust.


I used an engine hoist to get the machine around. Very handy to have in the shop.


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## rfurzer (May 11, 2022)

Radials said:


> An engine hoist in a small shop is a necessity in my opinion. I have moved this machine 3 or 4 times along with lifting all the heavy sub components and it's still proven to be the best money I've spent in the shop thus far. It's also what makes doing all this solo even possible.
> 
> The teardown was pretty straight forward. I downloaded the Grizzly G0730 manual for a parts and assembly reference. The Grizzly model is identical to this mill. It's since been discontinued however but the G0731 is still available except comes with a factory x-axis power feed.
> 
> ...


Was the spindle nose cap right or left hand thread? I once tried to strip mine, but it was either LH or very very tight


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## Radials (May 22, 2022)

rfurzer said:


> Was the spindle nose cap right or left hand thread? I once tried to strip mine, but it was either LH or very very tight


In my mind I'm not remembering the threads being LH, but I honestly don't recall at this point.


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