# G0773 Lathe / Mill Combo



## BROCKWOOD (Nov 3, 2018)

To start, if you have searched on this forum for the Grizzly G0773, as I have, the most notable comment, & I paraphrase, "Lotta money for a little machine." Yet, it doesn't fit neatly into the benchtop group because it is kinda big for that group - yet the mill portion is really small for that group as well. So, no-one admits to having 1 or all have stayed clear. Given parts replacement can take 6 months, it may well be that few are sold. 

I knew I needed a mill when I went shopping. Didn't need much in size as my interest was in making parts for bass guitars. Now I am new to milling, not that I hadn't admired the trade - cause from a young age I have & do admire the trade. I just don't know the trade. But, I ventured that for a little more money, I could have my small mill & a lathe all in 1.

Here it is loading onto my bench.




Now back in the early 20th Century it was understood that tools of the trade here in the USA needed fine tuning once you bought them. Hand Planes are a fine example of this truth. I had no illusions of my Grizzly being good to go.  First challenge was getting the compound on the cross slide to rotate 360 degrees. This is best solved by making a plug that allows the T nuts for the cross slide to glide across the access hole for the T nuts.







More to come & by all means, if you have this or similar please share your improvements!


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## mikey (Nov 3, 2018)

Congrats on the new machine, Brockwood! Reminds me of the Emco lathes that had a milling column attached to the lathe bed in the exact configuration you have there. While limited to smaller work, I'm sure it will come in handy for the occasional light milling job. 

The lathe looks like a 12X36? Has a separate saddle drive shaft so this is not your lower spec mini-lathe, and I like that the cross slide had full length T-slots so you can rear-mount tools (like a parting tool). 

Looks good!


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## BROCKWOOD (Nov 3, 2018)

12 x 27 so still a little short there. Feeds n speeds are in X & Y directions. I split the power feed into dedicated 20A Lathe & a separate dedicated 20A Mill for the sole purpose of power feeding under the mill as well. No wiring changes required. Just unplug the mill power from the intended source & using an extension PC power cord, plug it into it's own source. Sub panel was a necessary addition in my case anyway.




I really hope others will share their experiences & remedies. I thank you for your input Mikey!


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## mikey (Nov 3, 2018)

Does the mill have an R8 spindle? That would sure make finding accessories a lot simpler.

My lathe is an Emco Super 11 CD, which is an 11 X 24 - small, very accurate lathe. For the work I do, the 1-3/8" spindle bore has been enough that the length hasn't mattered too much. Looks like a nice lathe - enjoy!


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## BROCKWOOD (Nov 3, 2018)

All literature indicated R8 for the mill portion. So I bought some R8 tooling. But mine was made before that change & has an MT3 spindle & tailstock. At least they are the same. Only had to buy 1 drill Chuck! Accuracy is much more important than size, yours sounds like a fine machine Mikey!


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## BROCKWOOD (Dec 5, 2018)

I've added a QCTP FINALLY. Whew. I bought the BXA cause it's good for a 12" swing right?! Swing is NOT the measure to dial in the size that is right for you. Center height above the cross slide is what matters. No, get the AXA for this model G0773. Whittling down tool holders to get the center height dialed in was an experience. The mini mill portion wouldn't put a dent in them, so I set them up on my belt sander to wear them down like a river over a rock - but only while I was present & near the switch. Yes, safety can add a million years to a million year project.

Now I don't deny being new to machining & relish the advise of those that know. You might've even seen the thread on whittling down QCTP tool holders yourself. I'll sum it up for those that haven't:  Get a 4 jaw chuck for your lathe, chuck up a tool holder center as near center can be without too much fuss & starting from the center it is possible to cut it down while feeding outwards. I had all ready measured how much to remove. It went surprisingly quick - especially compared to the million years my own erosion plan would take. Doing the best I could, I do still have to admit that facing them on the lathe - as a compromise - left a tit in the middle of the face. The little tit came off quickly on the belt sander.

Another thing I finally checked was actual feed per revolution on the cross slide handle. The dial reads l to l = 0.001" yet, the numbers only count to 80 per rev or 0.080". Each revolution with a known good dial indicator is actually 0.100". Can't find the thread where a guy is making a new cross slide screw & nut for his Chinesium lathe. People cut him down for going to the trouble of making a 100 division dial. They essentially said that a precision dial on a imprecise screw is like lipstick on a turd. Must've seen that on another site. Anyway, you can dial in your backlash & as long as you only take your measures with feeds in 1 direction (again only 1 direction), you are not straying from your goal. I say this + a dial indicator for a good proof that you moved to the correct spot is just smart on any machine. Here's the part that I didn't like & it made me mad:  You can't cut down the manufacture of a screw that is owner made unless he gave you that screw (only then could you know if it was any good). So, as delivered I must do the math conversion 0.040 on the screw is = to 0.050" or I could make a new scale to fit the dial & know it matches the dial indicator.

Finally, I'm a little more proud of my lit'l Grizzly. I chucked a 25" piece of 1.5 bar & managed an 0.035" cut the entire exposed length on auto feed!


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## Aaron_W (Dec 5, 2018)

I've never been a fan of combination items other than the Swiss Army knife and Leatherman tools. It always seems like one part breaks or becomes obsolete leaving a weird item that doesn't work, but works too well to throw away without guilt. TV / VCR, washer / dryer unit.

On the other hand I've known a lot of people who got stuff cheap because of that. It seems like every kid who grew up in the 1970s was gifted a stereo / turn table / 8 track player from an older sibling, aunt / uncle etc when 8 tracks went out of style. Usually got it with one 8 track cartridge, Iron Butterfly or the Bee Gees seemed popular.

For a time my dad had one of those big console TVs with a stereo and turn table. The TV didn't work so he used it as a stereo and had a TV / VCR on top, the VCR part didn't work so he had a VCR next to the TV / (broken) VCR. The only thing he actually bought was the VCR, the rest he got for free.



Anyway, I think that is why you see some disdain for mill / driils and combo lathe / mills. They sell enough of these that you have quite a few options to choose from, so they obviously fill the needs for some, such as yourself. If it works for you that is all that matters. The mini-lathe / mills get much of the same, it is hard for some with a 1 ton lathe to understand how anybody could be satisfied with a lathe that a child can pick up and carry.



If you were able to figure out which lathe and mill are closest to those used on your lathe / mill you might have better luck getting answers it you treated them as if they individual machines except when it involves the fact that they are joined at the hip.


I give you credit for ingenuity and determination downsizing your QCTP, but wouldn't it have been easier to return it and order the AXA size? 


Is this the thread you were asking about? He is replacing the lead screw on his 9x20 lathe.

https://www.hobby-machinist.com/threads/9-x-20-half-nut-problem.74021/


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## BROCKWOOD (Dec 5, 2018)

Thank you Aaron. Savarins 9x20. That's it. Still learning my way around.


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## BROCKWOOD (Dec 5, 2018)

Though I agree that the swap to the AXA size would have been the most prudent solution to my fitment challenge. I have a large lathe in my future & want to keep the tool holders interchangeable.

Ah, the combo packages for so many things right up through the middle 80s really. I have a Zenith portable radio / phonograph from the 30s. Must weigh 25 pounds & plays 78s. I have a huge RCA Stereo Console from the 60s that is made of real furniture grade wood that still works great too. Good idea on concentrating on either the mill or lathe for ideas from others with similar machines!


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## Aaron_W (Dec 6, 2018)

Ok, I can see how it could be useful to have both lathes use the same size tool holders.


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## BROCKWOOD (Dec 8, 2018)

Another good mod for any lathe is to add holders for everyday tools. T Handles will always need to be close (but nut in the chuck when not in hand). My lil combo uses 6mm for most everything, so I included it in my holder design. I made it using 1/2" electrical thin wall conduit.


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## BROCKWOOD (Dec 20, 2018)

I've actually had this lathe 3 years last April. Now I've done it. Really! By all appearances, I've fried the lathe motor. Made a pass, turned it off, set up for a new pass, turned it on & HMMMMM. Maybe a start cap, so I turned the chuck. Nope. Every manual for every machine states, "leave room to access from the rear." Of course I didn't. It's a 2 car garage full of car parts.

Specs call for 115V 1700RPM. Grizzly doesn't seem to offer it anymore (was just checking my options). Seems nobody does 1700RPM & Grizzly is into 1ph 220V for similar offerings these days. 

Gotta get the motor out & see if it is repairable or rebuildable. Pics as I gain access. Of course getting all strain off the motor to retry spinning it up to speed proved useless.




Couple pics of diving into the belly.


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## Mitch Alsup (Dec 20, 2018)

You are going to have to move it away from the wall.

But it is likely that the start or run capacitors have turned to toast and that the motor is not completely dead.

Good luck.


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## Aaron_W (Dec 20, 2018)

That is a bummer, 3 years seems a short life for a motor unless you run it a lot. Hope it is a relatively simple fix. 

If not it 1725rpm seems to be a fairly common motor speed, I wouldn't think they are so picky that an extra 25 would be an issue. My lathe has a Baldor 1725 rpm motor that can be wired 115 or 230v.


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## BROCKWOOD (Dec 20, 2018)

Just looked at what it would take to move it all out from the wall. Gotta see what I can do to avoid that. In the end Mitch is right for best results etc. I'm not sure that 1 of the motor bolts is even accessible with the lathe mounted to the table. 

Aaron brings up a good point about motor RPM vs Speeds & Feeds. At 1st blush, speeds must be affected, right? Going from 1700 to 1725 RPM isn't much, but still should ......... Math best left to ponder at a later date.

So, here is the lay of the land.




Needs a reorganization anyway.


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## BROCKWOOD (Dec 24, 2018)

Well, I knew I wanted to take the motor out to at least clean & inspect it. (Was leaning on it being bad.) And I knew I wanted to make the motor serviceable without unbolting the lathe from the table or moving the table. Plans are to add an inline connector to the wiring as it exits the motor & to use studs with nuts in place of the 4 motor mounting bolts. As an inquiring mind, I went ahead & pulled the F / R switch to see how it works. Motor wires had to come off anyway.




I've cut out the Mill portion of the diagram. It's on a completely different circuit now (as discussed earlier). That switch & connection are labeled AUX. The F / R switch (CCW / CW) has 4 jumpers that do not show up in the stock diagram. That is how the switch comes. I've added them to the diagram. So here is how the switch works.




I do believe we have solved the puzzle. 1 of the plastic spring retainers had melted just enough to prevent Z2 from ever making contact.




This switch is 1 - 2 months away if I order today. Really looking for a better switch that is much easier to get. Any ideas?


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## BROCKWOOD (Dec 25, 2018)

Old switch is rebuilt (from the pile of parts seen above) & ready to go - short term. Contacts are burnished & the melted plastic cut away for smooth contact + make / break functionality. Next it was on to pulling wires through the conduit they are routed in to get to the motor. Turns out the Z2 wire has melted to the wire casing for the chuck guard limit switch down inside the conduit. Gonna need bigger wires with that better rotary switch. I don't need to go up by much - 1 better wire size with good insulation & really just wanting all this to be good for 20Amps min.

Thoughts & recommendations are always welcome?


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## FOMOGO (Dec 25, 2018)

12 gauge fine stranded wire should be fine for your application. Mike


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## BROCKWOOD (Dec 26, 2018)

Thanks Mike. I have 12 gauge stranded rounded up. There is a piece of conduit that runs through the gearbox. Looks like water pipe - only very thin. Well, it did not like the heat that had built up. Wiring sheaths stuck to it like glue. I have a thick wall cold water pvc pipe. But I'm leaning toward cutting down a piece of electrical PVC into a trough for the bigger wires to lay in.

Been looking at barrel switches. Exact replacement is just going to burn up again. KEDU makes a higher amp version - but nothing on the shelf here in the states that I could find. Dayton / Eaton have readily available barrel switches, but I am not able to picture how it would wire directly in place of what I have.  Lots to ponder.


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## BROCKWOOD (Dec 30, 2018)

The GE SB-1 switch comes in just about any configuration you can imagine. Still available new & much higher than what is listed on EBay.  I happen to have saved a few old versions. Just change cams to fit your application. Might have to make my own cams though. Too cold in the shop, so mapping this out for current & future projects is fun.


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## BROCKWOOD (Jan 2, 2019)

Got the motor out. Quite the physical therapy for recovering from back surgery. New switch needs new cams. Just a little each day!


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## BROCKWOOD (Jan 5, 2019)

Had to modify a couple of cams to get the switch to work as needed & added return springs. Good positive feel going on in either direction + snap action off from both forward & reverse. The other stock switch was Lathe - Off - Mill. I want Off - Lathe - Lathe & Aux. So I put together another switch. For now the Emergency Off is all that will be left of the stock controls.




Time to make mounts & wire this up!


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## BROCKWOOD (Jan 6, 2019)

Motor leads upgraded & mount studs installed. Getting there!


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## Aaron_W (Jan 6, 2019)

BROCKWOOD said:


> Had to modify a couple of cams to get the switch to work as needed & added return springs. Good positive feel going on in either direction + snap action off from both forward & reverse. The other stock switch was Lathe - Off - Mill. I want Off - Lathe - Lathe & Aux. So I put together another switch. For now the Emergency Off is all that will be left of the stock controls.
> 
> View attachment 284215
> 
> ...




Did you buy or build a new switch? 

I'm ok with mechanical stuff, but really not a fan of wiring and electrical work. Too much like black magic for me.


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## BROCKWOOD (Jan 6, 2019)

Just old retired switches I had laying around. Built to last forever. Company wanted new tech, so I held on to these. Had to make cams to fit them to this purpose. So long as your switches are rated for the machine you have, just change out as needed with the same switch. My Grizzly needs better than it was built with, so here we are. Dayton makes a fine drum switch for a motor. But I prefer seeing what I can do with what I have laying around.


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## BROCKWOOD (Jan 7, 2019)

Looks like my switches could fit up front where the original switches were. But, I have a better plan. I return to my job tomorrow, so this will have to wait.


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## BROCKWOOD (Jan 13, 2019)

I wanted to mount the switches out back & run handle extensions through to the front. This would require making couplings & some sort of bushing out front to support them. Either way, I needed & ordered a sheet of aluminum. As built the 2nd switch maintains lathe power while switching the auxiliary on & off. Well, parts for 3 bank switches, such as shafts & housings, I have. So modify parts for the 2 bank or add the 3rd bank? I've decided the added bank will maintain power to the Aux while switching the Lathe off. So it's back to cam design. Here is 1 of my renderings as I began to figure the timing of each cam. Despite best efforts to look, there are neither Edelbrock or Iskenderian in my DNA. I'll get this sorted before my aluminum arrives.


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## BROCKWOOD (Jan 18, 2019)

Well, I left the power switch I had dialed in off to the side & started assembling a new one with 3 banks. I set the limit to 4 positions, stacked the 1st 2 banks & had everything I needed. That is OFF - LATHE - LATHE + AUX - AUX. The 3rd bank became the + ??? to the AUX.  It's a mystery position that will remain unused - for future needs.

Aluminum for the faceplate came in & I've marked it for cuts & bends. Just not up to it right now. So I made a label for 1 of the switch covers.




At left is a cover that had whiteout labels on it. It didn't clean up as well as I had hoped. Middle is with my new label installed. Right is for the F / R switch. In it's original use, the handle would return to the center position after TRIP or CLOSE were selected - but the target in the window would remain RED for CLOSE or GREEN for TRIP. My handle will stay in the selected position & when it is turned off (straight up) the last direction used remains in the window.

It's really down to jig sawing, bending, drilling & wiring. So glad I can walk again. Just have regain my strength slowly.


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## BROCKWOOD (Jan 22, 2019)

Just have to regain my strength slowly. Sorry, I couldn't find the edit button to fix that sentence. So my task is to make a front cover to house the switches. I went with 6061 aluminum & then remembered that I've never bent it brfore. I cut a slice of it wide enough to become the sides & experimented with it. More to come.

.
	

		
			
		

		
	




I'll leave it at this for now:  Bending 6061 Al has it's own set of challenges.......................


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## BROCKWOOD (Feb 11, 2019)

I did bend the 6061 & thought it came out terrible. Here is the surround for the front cover that will not be used.




I decided to go with 10 gauge wire just for the front to back harness with a terminal block on each end. Had to modify a 12 term block down to 8. I'm working with old stock that's been laying around for years. When is the last time you saw a modular terminal block?! I plan to use 12 gauge hinge wire for the rest (as seen coming out of the motor).




Sure looks clean back here! A plug was added for the Aux. Supplemental, really, since the computer style connector remains.




Getting there & really ready to get back to making parts for the B&S 2 dividing head.


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## BROCKWOOD (Feb 11, 2019)

Buttoned up the back. Next time it has to come off, undoing only 4 wires + a ground allow it to separate as a complete subassembly. I hope it isn't 3 weeks before my next update. For now, it's off to work & ordering up more wire & lugs.


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## BROCKWOOD (Feb 18, 2019)

I have loved using 6061 in 1/8" plate for making flat panels. Once I saw that it wouldn't bend to my desired shape, I ordered up a sheet of 3003 in 1/16" sheet. I knew I wanted the edges to be rounded, so, though this is a shapeable aluminum, I had my work cut out for me. I began with a piece of paper to see what a corner cut line might look like.




I can't even get it to turn out right in paper. So, I've ordered up some quarter round aluminum extrusions. This should postpone my foray into how to hammer out a Ferrari GTO body. More importantly, this should get me my lathe running much sooner.

Back to waiting on parts, but staying busy with prep work. Only the front panel & wiring remains. All the wiring in every other part is complete & buttoned up. I rounded out the 2 bottom corners & retired the gear cover safety switch. I will keep the chuck cover safety switch in use. That's the 2 wires sticking up out of the power / motor bus. The Emergency Stop will now kill the Lathe (as it always did) & the Aux too once wiring is complete.




SB-1 switches sometimes called for a factory jumper. I decided to make some out of brass. Factory jumpers are in the background.




Clickspring makes shaping brass look easy. Well, I am doing 4 at once. I'm also working up the schematic of the as finished changes. Keeping busy & having fun getting there!

In other news, Grizzly has dropped the G0773 from their 2019 catalog. Their latest combo is based on the 4003 series. It uses 240V single phase & the mill no longer has the left / right column tilt debacle (feature). My mill portion will get upgrades at some point - but that is a story for another time.


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## BROCKWOOD (Feb 19, 2019)

Wiring Diagram complete. 1st drawing is before & 2nd is how I will wire it with better everything - except for the switch for the chuck guard & the kill switch.


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## BROCKWOOD (Mar 3, 2019)

Finally starting on the front panel. Too much overtime to move along as quickly as I'd like. Still have trimming & fabrication to go - but any progress is good!


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## BROCKWOOD (Mar 8, 2019)

Well, with these big ol switches, I needed more mounting space. A little jigsaw, a little Dremel & some big files!




Could have just made it all fit, but prefer making it as professional as we had in the old days! & yes, I am slow on account of my tools are slow but steady! Hey, helps me regain my strength in measured steps.

Lots of filing & shaping left - but getting there & as always, just glad for progress at this point in the game!


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## BROCKWOOD (Mar 14, 2019)

Trying to come up with a commercial grade finish is tough. Just hoping to start wiring by morning.


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## BROCKWOOD (Mar 22, 2019)

Front panel & mounting complete. Parts installed. Factory pic then a few of my finished upgraded panel. I really hope to always have a lathe & mill to help with every one of my future projects.


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## BROCKWOOD (Apr 13, 2019)

My favorite part about this site is how we all take the label "Hobby" as a good thing! I don't have the time constraint weighing on me. No constant compromise between finish the job & quality. Plus, this only gets to happen when all else is done for the day.

When we left off 3 weeks ago, the front panel fit as designed & it was time to just finish connecting the wiring. Well, it didn't go that easily. After adding just a few wires to the front panel, I decided to check fitment to the lathe. No Go. I had to cut an additional 1/2" out of the lower lip.  




Now the loom is complete with my 1st ever old school wax string wrap (think pre zip ties).







The safety switch (for the chuck cover) wiring is too short. It turned out to be 16 gauge, so an upgrade had to happen. Having never found a replacement that I thought ideal, it was time to see what could be done with what I have.




Just like all the ones I've found on line, there is a NO & a NC contact. Stock is the lower of the 2 in the pic. I've converted the top one to 2 NC contacts, removed a ribbing on the perimeter center & am making brass jumpers. This will bump the amp rating to 24 & the wiring will be 12 gauge. Slow but steady & making progress. It's a pleasure to do this work without a time clock! I also need to grind out the right corner in the last pic. The wiring loom needs a place to bend onto it's final approach at the terminal block on the chassis (behind the paper towel). It's designed to just pull the front cover away & flip it upside down to rest on top for disconnection & servicing. Cool thing is when you design this much fortitude into a product & also plan ahead for servicing:  The need for servicing goes away!!!!!!!!!!!


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## BROCKWOOD (Apr 17, 2019)

She's alive! Well, now I need a new start cap. Yep, had to spin it up by hand. The good news is that with all my modifications, I had the motor back out in less than 30 minutes!


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## BROCKWOOD (Jun 29, 2019)

Start cap I went with was too long for the housing. Modified that & now it's a tight fit poking out of the housing. I should've taken a picture of that.  Then, I had the motor mounted & removed 3 times in a single day & still could not get this lathe to power up on it's own. So, I took the motor to the motor shop & turned my attention to other projects. A month later I went & got my motor back. It was never touched or worked on. The centripical start contact has since been filed & polished. So, it's mounted & as long as I help the spin up when starting & only use the E Stop  for quitting:  All is well & more chips are happening as of today! This has been so important to me in part because I'm using this lathe to build parts for other machines that I'm restoring.


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## hman (Jun 30, 2019)

Don't know if this is related to your motor problem, but ...
The motor on one of my bench grinders went "unstart" on me a month or so ago, but I was able to get it to run by spinning up by hand.  Opened it up, checked the start switch contacts and capacitor ... no problem.  Reassembled, no start.  I finally figured out that the rotating part of the start switch had slid sideways on the shaft a bit, preventing it from closing the switch.  Loosened the setscrew, moved the switch over, tightened the setscrew, and all is now well.


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## BROCKWOOD (Jun 30, 2019)

HMAN, This is definitely food for thought & I thank you for your input. Mine has a horseshoe affair, with the start contact in the middle of the curve, mounted inside the end cover. The centripical spring pack has a plastic ring that either rides against the contact in the run position to force the contact open or springs back. Perhaps it has shifted on the shaft? This is going on my to do list next time I have to get back to that area.

As for now it is working! I'm needing an 11 TPI for a part I'm making - seems everything on my mill is 5/8 - 11.

I'm about to do the math & make some changes. Here is what's available.




You can be sure my next lathe with include 11, 13 & a host more TPI selections.


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## hman (Jul 1, 2019)

Just for fun, I tried playing with the probable gear ratios that might produce a threading table like you have.  Couldn't figger out any "G" gear that would get you to either 11 or 13.  MAYBE you could swap some other gear for one of the 1,2,3,4,5 or A,B,C gears.  But as far as I can tell, playing with G just won't do it.

On the other hand, I think there's a way for you to get 27 TPI (which some members have posted about not being able to get on their lathes).  It would require a 40 tooth G gear, and setting 1-B.


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## BROCKWOOD (Jul 1, 2019)

Thanks hman!  I played with the chart more today EDIT:  07/02/2019. hman shows the math a little further down. My attempt at playing with ratios was off. So this is just the open gear section without an incorrect chart.





I'm about to go slap the 35 onto the G spot, set the dials to 4 - C & check my math. Update by 2300.


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## BROCKWOOD (Jul 1, 2019)

1st run.




My thread gauge only goes to 40. Forgot to change the dials. Should be 66 TPI.

OK. Set the dials.




That is off a bit.




5/8 - 11 stud matches the thread gauge - but still shows this is off a fractional bit over the course of an inch. The disk on the right side of the test subject is what I need to be 11 TPI. I think I'll venture it. Unless $7 - $10K appears as an unexpected blessing......... I'll see if this will get me there or cut my diameter to fit inside the threads, thus clearing them altogether.

I think this is a case of [my math was wrong]. The difference actually does stack up to cause an ever expanding error as length increases. When is 3 3rds not a whole? 0.333 / 0.666 / 0.999....................... As much as I wanted to truly understand this, I simply could not move this beyond simple ratios.

In conclusion:  My chart is plain wrong, but hman straightens it all out below!


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## hman (Jul 2, 2019)

Unfortunately, I have no way of knowing the gear sizes (tooth counts) represented by A,B,C or 1,2,3,4,5.  The way I approached the problem was to use the formula: Combo/G=TPI.  For instance, using the second-to-last line of your chart, 4C/30=12TPI leads to 4C=360.  Checking, 4C/60=360/6=6TPI.  That works.  Now plugging in G=25 and G=35, I would predict 14.4 and 10.29 TPI, respectively ... NOT the 13 and 11 you were hoping for. 

Just for fun, I worked up a quick spreadsheet (using Open Office, not XL - don't have XL on my Mac).  The upper half calculates the "fudge factors" of all the 12345ABC combinations, based on your TPI original table and G=60.  The lower half calculates the result of changing G.  I've included two such tables.   The one for G=30 is intended to check the math.  It correlates with the G=30 settings on your original table, so I'll claim that my math is correct.  The one to the right sets G=40, and you can see where I got 27 TPI for 1B.

I don't know how successfully I can reformat the spreadsheet for XL.  Open Office can supposedly do that, so if you want me to try, send me a PM.


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## BROCKWOOD (Jul 2, 2019)

hman I thank you for taking the time to show me the right approach to this! I'll have fun doing the math.

So I made a spread sheet that would do the math & played with the 'G' gear tooth count.




Assuming a smaller gear than the stock 30T could fit, I see some benefits to making these gears. But as hman stated, nothing gets an 11 TPI with just the 1 gear change.


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## BROCKWOOD (Oct 15, 2019)

Well, I did it. I wore out the timing belt that goes between the motor & idler puller. Grizzly doesn't offer the belt listed in my parts list & the local supply house couldn't match it either. So, I went about my search on google & found 1 from Grizzly. Grizzly has completely retired from servicing my lathe - but carries what I needed under a new part no for a different machine. I bought 4!!!


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## BROCKWOOD (Oct 24, 2019)

Oops, forgot to include the pics & info. 
	

		
			
		

		
	







I have since learned that part of my problem with tearing up the timing belt was over tightening the other belt. it couldn't slip any more. Never mind it just jumps off otherwise. Always something to bring out the 'engineer' waiting to be designed out of these things.


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## BROCKWOOD (Oct 28, 2019)

Some might remember this has the BX QCTP installed (retrofitted). It's always different from the intended design with this model as the mount is simply a post (stud) as opposed to the usual wide T slot. So, I turned the end of the new post down & threaded it & away we go! Recently, I lost the ability to loosen the top nut for angle adjustments. The whole thing moved. So, once the part I was working on was complete, it was time to get to the bottom of this. I pulled the set screw out of the cross slide with the intention of drilling an indent in the stud. Not happening. Long story short: Clock the stud & mill a flat into it! I went up a size for the set screw while I was at it! Not gonna be a problem any more! 

Also, I made a holder for a - not sure what to call it. When loosening the drawbar on the mill portion a rod is needed to insert into a hole in the side of the spindle to counteract the loosening. I'm using a steering wheel tilt stalk because it's longer & more comfortable. The holder is from scrap.


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## BROCKWOOD (Nov 6, 2019)

For my next trick, the 80 total graduations on the crossfeed dial have to go. A single revolution does equal 0.010" so it's high time to regraduate this to the proper 100 graduations. Step 1 is finding a  1/8" set of number stamps in a likable font.





And, Yes, the trick will be doing this successfully on the 1st try. I'll be using a dividing head if I can work out the setup. It's all new to me (Pretty sure I'll be saying that for years to come).


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## BROCKWOOD (Feb 15, 2020)

Sorry, haven't found the font I want for new numbers in the 1/8" range. So, I've put it back together for now.
I had such great success in making the drawbar for my larger mill, that I thought to make a drawbar for this Grizzly. 



Part of my frustration with this Grizzly mill is 'shudder'. It isn't rigid enough. I've added a shim behind the rack, so downfeed is, eh, better. I also noticed an imbalance caused by my assortment of make shift drawbars.




The 1 at bottom is good to go, but it seems silly to have 3 different ones for the same size thread - 2 of which don't center in the spindle. 

In making the new drawbar, I got very frustrated with the 'shudder'. My vibration even loosened my end stop. Doh. I had set aside some end mills for my big mill that a friend gave me. Oh to have a real quality in a cutter in this Chinesium challenge!




My real question here is:  What have you all used to fill the mill column with to add rigidity? I've heard, use epoxy. OK great! Any recommendations for a specific product?


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## middle.road (Feb 15, 2020)

New to this thread.
Where are your pictures of the 'new' "Big Mill"?   
Going through this thread it would appear to me that you made silk out of a sow's ear.


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## BROCKWOOD (Feb 15, 2020)

Working on the 'Sow's Ear' for sure Dan! Always open to advise too. Ah, the big mill? I'm still sorting out the bits on it * honestly working up my skill level to be able to operate it. Needs sump sorted & a leak on the table & still need to run power to it. But, yeah, here she is. Quite the step up.


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## middle.road (Feb 15, 2020)

BROCKWOOD said:


> Working on the 'Sow's Ear' for sure Dan! Always open to advise too. Ah, the big mill? I'm still sorting out the bits on it * honestly working up my skill level to be able to operate it. Needs sump sorted & a leak on the table & still need to run power to it. But, yeah, here she is. Quite the step up.


Just a 'wee' bit of a step up from the Grizzly 3in1... pheeeeew, boy howdy, that be 'Big Iron' fer sure.   
What is the Make & Model?


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## BROCKWOOD (Feb 16, 2020)

Aye Dan from a pebble to a mountain! That is a Van Norman no24 from 1959. I won't trouble the details here as it has it's own thread https://www.hobby-machinist.com/threads/van-norman-no-24mla-1512-259.60855/


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## BROCKWOOD (Feb 25, 2020)

Sometimes it's the little victories. Certainly true when improving this Combo. So, I've added a 0.030 shim behind the mini mill rack to reduce slop. Helped a lot on the downfeed - but, really, not impressed with the design. Seems an ACME screw would be much better. I'll be doing away with the tilt feature eventually as part of a 'beef it up' plan. 

Today, I made a drawbar for it to replace the several bolts I was using for different attachments. Vibration is reduced! These 2 are all I need now:




The rest can rejoin the bolt & screwdriver collections!


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## BROCKWOOD (Nov 1, 2020)

My latest upgrade to the Grizzly is finished. Well, not really an upgrade - more of a storage addition, though it did require better hinges for the gear cover.







Hinge modification is below.


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## BROCKWOOD (Sep 14, 2021)

A few additions, changes & updates!

Added a small shelf to the organizer on the end to store mag bases.



	

		
			
		

		
	
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Now 1 of the purposes for having added that Aux feature is in use today! The switch incorporates the E stop to kill the Spindle as well as the Aux.




At present the Aux feeds a tool post grinder.




Sorry, I've flipped that last pic 3 times & changed the file name twice only to still have it attached upside down.


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