# My own Grizzly DF-1237G setup/restoration thread



## TonyBen (May 22, 2019)

Not to hijack the other guy's Grizzly thread, I'll start my own. As I stated in my "Hello" thread, I was gifted a Grizzly DF-1237G 12"x37" lathe. I had an electrician come in and wire the garage for it and the Jet JMD-18 mill/drill I was also given. 

The cross-slide had some terrible slop in it. I had to turn the wheel one full revolution before it would change directions. Somehow, I had an epiphany this morning and checked the screw that holds the cross-feed nut in place and from the top, I could see it wiggle as I moved the knob. I quick 1/4 turn with a 6mm Hex wrench and my full turn of slop turned into 1/8th of a turn of slop. I still get a loud CLACK-CLACK-CLACK sound when I turn the cross slide wheel.

I guess the main thing I really need to do is work on the accuracy of the lathe. To re-hash over what I already stated in a couple of other threads, my 3-jaw chuck was in terrible shape. It had about 0.050" runout. I have it disassembled and it was really dirty. I did check that the jaws were in the right place, and they were. As soon as I have more time, I'll clean them out and re-assemble them.

I've been able to chuck up some pieces and get runout in the 4-jaw down to about 0.0003" of runout. I have some junk 1/2" steel shafts that are nicely machined and straight that I got form a scrap bin at work that are about 12" long. They appear to be precision machined. Over roughly a 9" travel, I get about 0.0015" of runout. Is that good or bad?

The headstock is not aligned with the tailstock. I checked this with the same bar, which has a threaded hole in it, and installed a Jacobs drill chuck in the tailstock with a demurring drill bit in it. When I advance the tailstock, it sits about 0.020" high. I haven't leveled the lathe yet, so I'll start there and see if that fixes the misalignment.

I did replace the terrible tool post with an Aloris BXA tool post set which came with a few nice quick change attachments.

I don't mind saving to get a better set of 3 and 4 jaw chucks that will fit the lathe. I just have no idea what to get.

Nez (Bamban) did text me last night and told me what kind of way oil to get so I'll get some of that ordered up licekety split.


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## RJSakowski (May 22, 2019)

It sounds like you have a project on your hands.  It seems like it has seen some neglect over the years but some TLC should give you a decent machine.  Good luck with it!


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## TonyBen (May 22, 2019)

Is it possible to purchase a collet style chuck for this lathe?

I'd be willing to save my pennies for a high quality 3 and 4 jaw chuck as well. I do need the ability to hold pieces as small as 1/4".

Tony.


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## Bamban (May 22, 2019)

Get an ER40 collet chuck, and buy a set of ER40 collets and you are good to go, these are even the adjustable type to dial the workpiece

2017-catalog-no-cover-compressed





						2017-catalog-no-cover-compressed
					






					www.shars.com


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## RJSakowski (May 22, 2019)

You should be able to adapt either a 5C collet chuck or an ER collet chuck to your spindle.  The 5C collets cover a slightly larger range but require more collets to cover the range.  An ER 32 will take you out to about 3/4" while the ER 40 will go to just over an inch.  5C collets are also available for square and hex stock, along with machinable collets for special needs.


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## TonyBen (May 22, 2019)

Perhaps the 5C to turn the 1.1” barrels? The ER40 only goes to 1”.


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## chips&more (May 22, 2019)

I would get a “good” 3-jaw chuck and postpone the collet set-up procurement. That’s my 3 cents…Dave


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## RJSakowski (May 22, 2019)

TonyBen said:


> Perhaps the 5C to turn the 1.1” barrels? The ER40 only goes to 1”.


Socket depth on 5C collets larger than 1" dia. is 1-1/4".  I would use a four jaw and dial it in.


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## RJSakowski (May 22, 2019)

TonyBen said:


> Perhaps the 5C to turn the 1.1” barrels? The ER40 only goes to 1”.


Or a "Set Tru" style chuck.


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## Bamban (May 22, 2019)

I agree with RJ, a set thru would be great all around chuck. I have a Gators 6 inch 6J, and a Rohm of the same configuration, Love them. Tony wants to go down 1/8 inch OD workpiece, both those chuck I have would not go down to 1/8. 

Maybe  6 inch 3J set thru would suit him, don't own one, don't know what would be smallest diameter they would close on.


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## TonyBen (May 22, 2019)

Nez, I at least need to get small enough to make a rear pillar. 1/2 to 1/4 would be fine. Was thinking it would be convenient to trim connector pins but I don’t have to have it. Gotta trim piston tails too. 

Tony.


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## Bamban (May 22, 2019)

For those items you mentioned, the collet system would probably your best bet. The ER40 is adjustable that you can dial the gas piston before cutting on the tail.

For barrels, later on just make a simple front spider. Here is what I built initially for my Jet 1024 with threaded spindle. The spider itself is sold at Grizzly.com, cheap like around 32 bucks. Later on, Akajun, a shooting buddy from the Cajun land and a member here, made one for me from steel stock. Bolted it to the same faceplate I initially used. Or, if your spindle has threaded nose,you can make a direct thread on spider, last picture.


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## Bamban (May 22, 2019)

To complement the front spider, you need to make a simple outboard spider. I use finger clamps with ball bearings front and back to allow the barrel to pivot as I dial the barrel bore.


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## Richard King 2 (May 23, 2019)

After you level the machine (I like your leveling pads)  chuck up a piece of aluminum round stock bigger then the tailstock quill and turn it down to the same size of the quill OD and then move the TS up to the turned piece...oh cut approx. 3" long.  Then mount a mag base on the compound and indicate the HS bar and TS quill.   Side first and align the side to side and then check the top of the 2 bars.  Have the TS quill extended out and locked and TS locked to bed.   That is the best way to check the height.  Many sweep with an indicator and forget that the indicators or bar sags.     You can also check the HS bar for taper.  On Those Asian machines the headstock sits on a swivel pin and the head can be adjusted to cut straight.   I have cut the HS bar using the 2 collar test as you can see in the pictures.


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## TonyBen (May 23, 2019)

Step 1. I leveled the lathe today. Never done this to a lathe and had to look at a couple of videos to do it. 
At the headstock..











Somewhere around the middle of travel...










At the tailstock end...





Is that good enough?

Tony.


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## Richard King 2 (May 23, 2019)

It looks good.  A simpler way and better way IMHO is.  to set the levels on top of the flat cross-slide and check it again.   When you use the cross-slide no need for the V blocks and no need to pick up the level.  It will follow the tool path too.  That bubble level is .005 /12" per graduation.


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## Dabbler (May 23, 2019)

To align your tailstock, you just can't beat Stefan Gottewinter's method shown in this video:  He directly reads the value in Z  (bu7t you can also read in Y just as easily - mine was .002 high in Y.


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## Richard King 2 (May 24, 2019)

I showed Stefan to do it that way.  He has been in 2 of my classes.  I need to tell my students to teach, but please give me some credit when they teach my methods!   I just scolded him on his you tube channel for forgetting to mention who showed him how to do that.


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## TonyBen (May 24, 2019)

Richard King 2 said:


> It looks good.  A simpler way and better way IMHO is.  to set the levels on top of the flat cross-slide and check it again.   When you use the cross-slide no need for the V blocks and no need to pick up the level.  It will follow the tool path too.  That bubble level is .005 /12" per graduation.



I had originally done it that way but thought it was too easy and there had to be more to it. I went looking for other methods and found the way I did it the second time, thinking that maybe the first was was inaccurate. I'll go back and re-level on the cross-slide. It won't be much effort. It's just tilted down on the working side. Shouldn't take me but 5 to 10 minutes of tweaking to get it back in that way.


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## Richard King 2 (May 24, 2019)

One other thing is to tap on the leveling pads with some leaded cold roll bar stock,  to seat them on the floor.  I hope I'm not coming off as a know it all here...but I have been leveling and aligning machines for 50 years and want to share before I croak.   This is a bigger machine, but the principals are the same.
http://vintagemachinery.org/pubs/2104/3558.pdf


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## RJSakowski (May 24, 2019)

The registration surfaces for the cross slide are the front vee and the flat on the rear way.  The rear vee  and the flat on the front way are the registration surfaces for the tailstock.  The assumption that all surfaces are true with each other is just that; an assumption.  The most accurate would be to use the top of the cross slide, as Richard suggests, as it rides on the registration surfaces used in turning.


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## Dabbler (May 24, 2019)

I 100% agree with Mr Sakowski and Mr King.  That notwithstanding, we are talking about making the readings the same - not to accurately level the bed.  The OP has a bed that is untwisted even if it is not level - and it need not be.

Yes it is far easier to use the carriage, AND that lathe has a ground cross slide which would make it very easy and  correct to use it for leveling.  Some lathes I've used, the cross slide top is not flat or straight and the base isn't stable.  Then using [123 blocks or vee blocks and a parallel] or Richard's fine alignment jig is essential.

There are many ways to skin every cat -  and it is important to let this OP who is newer to the trade, that his job was done well.


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## TonyBen (May 24, 2019)

Richard King 2 said:


> One other thing is to tap on the leveling pads with some leaded cold roll bar stock,  to seat them on the floor.  I hope I'm not coming off as a know it all here...but I have been leveling and aligning machines for 50 years and want to share before I croak.   This is a bigger machine, but the principals are the same.
> http://vintagemachinery.org/pubs/2104/3558.pdf


 You all know more than me. I never discount any bit of knowledge that is shared. Thank you for sharing that. 

I have made a name for myself by listening to silver-haired folks that were long in the tooth in a niche market and documenting what they knew while they could about my favorite rifle. Most of these individuals were not computer or video savvy. There was no single source on the internet for their knowledge, so I decided to make one, sharing what knowledge I collected from them. Somehow, I became the guru for that rifle platform and my "How-To" videos have become essential viewing for anyone just coming into that specific platform and I cover basic and advanced gunsmithing and accuritizing of that platform. Everything I post though, does not include any machining but rather all hand-fitting since, until now, I had no machining equipment or experience.

My YouTube page (tonyben3) happened completely by accident and wouldn't have happened if other experienced people kept their tricks to themselves.

I value every tip and trick anyone can share. Thank you all!

Tony.


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## BROCKWOOD (May 24, 2019)

Looks like fun! Grizzly's can be frustrating, but also very satisfactory once lined out for your purposes!


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## TonyBen (May 24, 2019)

Well, I don't have a round bar that is as big as the quill of the tailstock, but I do have a rectangular block of aluminum that is larger in its smallest width than the quill is wide. I chucked the rectangular block in the chuck and started to use the feed control to make the cut with my carbide cutter. I don't know what happened but when I reached for the clutch to disengage the feed, it either jammed, or I pushed it the wrong way, or I grabbed the wrong lever, or something, but it didn't disengage. I hit the chuck and sparks flew. I was using the slowest feed possible. Luckily, since its a belt drive and the belt is somewhat loose, the motor spun but the belt slipped which stopped the gears from turning.

The carbide cutter broke and the chuck stopped. I cut power somehow managed to break everything loose. I thought for sure I buggered up some gears or something. Looks like the worst I did was break the cutter. Luckily for me, I had just bought some new carbide bits (the kind you can replace the tips) and I put in a new bit.

This time, I rehearsed engaging and disengaging the clutch. A new habit for me; when running the feed, never take your hand off the clutch. I continued cutting and am about half way to making a round bar out of a rectangular bar. Just for safety's sake, I would disengage the clutch a couple of times throughout the pass to make sure it wasn't going to jam on me before I got any closer to the chuck.

OOPS! 

I'll finish turning the block tonight. That was just how I spent my lunch hour today. My heart rate is settled down a bit now. And yes, I was wearing safety glasses.

Tony.


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## BROCKWOOD (May 24, 2019)

Didn't have mine long before I broke the cross slide. I confused the direction at the end of travel & engaged auto feed in the wrong direction. Major OOPS. You're doing good by exercising caution!


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## Dabbler (May 24, 2019)

For a small cut like that I have always hand fed my cuts.  I very seldom use the feeds on my 12X37.  Not only for those 'oops' moments.  You can really feel your cut when you hand feed, and in some cases do more accurate work.

--You only need to take  .250 in Z or so to make the dimension the same as the tailstock.  BTW for interest's sake what is your measurement?  U using a mic or a vernier?


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## TonyBen (May 25, 2019)

Dabbler said:


> For a small cut like that I have always hand fed my cuts.  I very seldom use the feeds on my 12X37.  Not only for those 'oops' moments.  You can really feel your cut when you hand feed, and in some cases do more accurate work.
> 
> --You only need to take  .250 in Z or so to make the dimension the same as the tailstock.  BTW for interest's sake what is your measurement?  U using a mic or a vernier?


Here's what I' was cutting. 






Here's the broken cutter.





I used the auto feed to get a better cut but after switching to a different bit, and changing the cut angle, I see that wasn't necessary. I think I had the cutter angle all wrong for what I was doing so as I was hand cranking, it was cutting finer lines, if that makes sense. I switched to auto feed to get a more consistent cut. 

It wasn't until after I installed a triangle carbide cutter and put the cutter at a different angle that I now see that I could have hand fed with good results.

Tony.


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## Dabbler (May 25, 2019)

Your lathe is quite robust, and I'd expect that you have leaned a thing or 2, but I'm fairly confident it was without detectable damage to your lathe.  Particularly your headstock has oversized bearings and is quite rigid for it's weight class.

I have no particular aversion to auto feed, I just like to feel the work.

--If you use cutters with a larger radius you won't have lines.  It takes a little practice to hand feed evenly, and get an accurate result.  In a few cases auto feed gives deceptive results:  the 'lines' are so regular that the eye sees them as texture on the surface, but there are furrows if viewed under magnification.  Think of using a radius at least 4-6 times the feed rate:  so if you advance .010 per revolution, a radius of .060 is appropriate, for instance.  [These are just rules of thumb I use;  anyone feel free to correct me on this]

[edit]  I almost forgot:  I hand feed quite quickly, leaving obvious furrows at first.  only on my final pass or 2 do I slowly feed.  This is also true for auto feed...

[edit 2]  You have that piece put waaaay out there.  I'd never go that far out even on the 15" LeBlond I use unless it is supported by the tailstock.  It looks like the piece is almost 12" long!   Just looking at your photo gives me a pucker in the wrong place.

To longest piece I'd use for this test would extend about 1" past the jaws, and I'd cut about .300 off it to the desired dimension.


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## TonyBen (May 25, 2019)

I eventually did have a revelation and drilled a hole for the tailstock. I don't have a live center but I just eased a dead center in there for the sake of supporting the part.






I'll hack off a 1" section and chuck it up in the lathe. The tailstock is 1.575". I only have a 1" micrometer so I'll have to use a verneer scale. Time for bed.

Tony.


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## Bamban (May 25, 2019)

The first projects I made when I got my lathe were a half a dozen fridge magnets for the wife. They were easy, but a good start to turn, bore, and face the workpiece to the sketched dimension. Plus, got a few point with the boss.


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## TonyBen (May 26, 2019)

I spent some more time on it this evening. I tore down the cross slide and the compound and scrubbed off the decades old petrified oil.

Before...






After...





Before...





After...





Before...





After...





Lubed it all up with some way oil and topped off the bearing reservoirs. 





I chopped off a smaller section of the bar I turned yesterday and started turning and facing the part. I'll work on turning it down to the tailstock diameter.





Everything except the compound is running real smooth now. Everything is pretty effortless. Everything runs quiet.

The compound is stiff throughout the travel. I adjusted the gibb and it doesn't matter where I put it, it's always stiff at least the last 1/4 of travel. If I get it as smooth as it can be, there's too much slop. I adjusted until I just had no slop at all. I think the gibb insert is warped.

Tony.


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## BGHansen (May 26, 2019)

TonyBen said:


> I spent some more time on it this evening. I tore down the cross slide and the compound and scrubbed off the decades old petrified oil.
> 
> Before...
> 
> ...


Nice job Tony,

Are you thinking of setting the gib on a reference straightedge to check flatness?

Bruce


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## TonyBen (May 26, 2019)

BGHansen said:


> Nice job Tony,
> 
> Are you thinking of setting the gib on a reference straightedge to check flatness?
> 
> Bruce


I think I recall when I put it back together it didn’t sit flush in the dovetail. But yes, I’ll put it on a granite slab. 

I turned the piece down to 1.575” just like the tailstock diameter and the chuck sits about 0.020” lower than the tailstock quill. I have to shim the headstock. 

Tony.


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## Dabbler (May 26, 2019)

Sorry Tony, it doesn't work that way.  It might in automobiles, but here's the scoop:

Your headstock is mounted on an area machined to be parallel to the bed and has the greatest contact area possible.  this is essential to keeping the bits in rotation (chuck spindle and bearings) as stable and vibration free as possible..  Take it from me, if your head is already in line you just don't want to mess with it... (unless your long term hobby is aligning the headstock - it is pretty tricky on this lathe.  experience.)

A little story:  when my lathe came from the factory with the factory 3 jaw  chuck in it, I grabbed a piece of 2" round Superior Shafting in it.  this peice was measured on good equipment and known to be within .0002 from end to end.  My runout at 10" was under .0005.  After moving my lathe where I foolishly removed the head, using the same bar and toolmaker that had done this dozens of times before,  the BEST we could do was to get the 3 Jaw to .012 runout.  On the 4 jaw, ;006 runout.  This was after dozens of hours of work on it.  

If you quill is .020 high (which is way higher than mine) then you have one fairly easy remedy...  If you have a mill.be SURE of all you dimensions because there is no easy way of going back...  You have to disassemble your tailstock and modify the LOWER portion.  This involves stripping it right down, and removing everything that sticks up.  You then take it to a mill that is running true, and make cuts on the bottom of the plate that will allow you to put it on parallels,  topside up.  You then take off the excess but for the last .002 or so.  (If your are feeling VERY lucky, you can leave .0015).

Now you have to get out the scraper, and use the surface plate and indicators to get it exact.

If you do it this way, you headstock and tailstock will have full contact and everything will run tight.  I know 3 others with this model through forums, and one other in person.  None of us is over .004 high, so I worried there might be a measurement error (I make them all the time).  Best to check 6 ways past Sunday before proceeding. Mo measurement is foolproof.


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## TonyBen (May 26, 2019)

Okay. I’ll get some more measurements. I like your idea better. The method I mentioned was from the factory installation manual.


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## TonyBen (May 26, 2019)

So I already have a drop of oil at the chuck side bearing seal. If I replace the bearings and seals, will that throw out any alignment I do now?

How much should I expect to spend on bearings and seals?  Anyone have a tutorial on this?

Tony.


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## Dabbler (May 26, 2019)

Unless your seals leak, there's no reason to change them...   Replacing the bearings with the correct preload will  not change the alignment on this lathe...  Several guys are waiting for one! Including me!


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## TonyBen (May 26, 2019)

Checked it with a height gauge on the cross slide. The tailstock is 0.013” higher than the headstock.


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## Dabbler (May 26, 2019)

wow.  just wow.

Things to try:  
o   check again with the tailstock barrel all the way in. 
o   remove the tailstock and reclean the veeway and the flatway..  
o   Dissassemble the tailstock and make sure the last guy didn't reassemble it with swarf between the two plates.  Also check for a burr in the mating surfaces.  Lightly stone the mating surfaces with a  flat stone.  Reassemble and try again.

Very nice height gauge!  envy!


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## TonyBen (May 26, 2019)

Will do. I also question if the headstock is even really aligned to the bed. There's no telling what was done to this by the previous owner. It will be nice to find out once the height is all sorted out.

Tony.


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## Richard King 2 (May 27, 2019)

Check for shims in between the tailstock half's .  Also turn a longer shaft in the headstock  6" .  Then you can speak in terms of per 12" by multiplying by 2.   When I showed Stefan G during the Stuttgart  scraping class how to turn the piece in the chuck.  We could not find a longer piece of material.   Turning a short stub like you and he does in can give you a false reading as the bedways up close to the chuck are worn the worse.  Also if you turn a longer piece in the headstock you can test the direction the head-stock points top and side. 

The tailstock .013" is unusual as heck and most of the time they are low and pointing down because the chips wear the front side of the tailstock.

Here is another student showing turning tests.





    fast forward to 1 min


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## TonyBen (May 27, 2019)

Thanks again! Until now I had not yet cleaned the way surfaces under the tailstock. There was a couple of decades of petrified gunk and some fine particulate buildup. I scraped the surfaces with a plastic scraper and hit it with some scotch-brite. Looks like cleaning the bottom took off 0.010" of error. I'm now down to only being 0.003" high.












I'll stone the ways a little more and see if I can bring them in closer. I'll also get everything lined up to make sure they are the same diameter.

Tony.


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## TonyBen (May 27, 2019)

SURPRISE!

I used the dial indicator to center the tailstock and to my surprise, after tightening the levers and the centering set screws, the offset is now down to 0.0005"!!! I also checked the size of the cut and there is a 0.0005" concentricity to it.











I still haven't checked the side alignment.

Thanks again for all the help!

Tony.


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## TonyBen (May 28, 2019)

I talked to my machinist at work this morning and he said 0.0005" runout on a fresh cut at the face of the chuck is way too much for him but he said for my purposes, it should be fine. He'd expect it to be under 0.0001" or near zero.

Tony.


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## BGHansen (May 28, 2019)

Boy, sure seems like for hobby stuff that 0.0005" would be close enough.  Anything tighter than that practically gets into "the Emperor's New Clothes" realm.  Not many of us here working on parts for the space shuttle.  Depends on your projects.  

Titanium Knurler (pretty sure) did the math on the effective diameter difference when cutting with a vertical offset on the tail stock.  It varies based on the diameter, but it's practically im-measureable for a 1" diameter turning.

For example, if you are cutting on center at the head stock and your diameter is 1.000", the radius is naturally 0.500".  If your tail stock was 0.0005" higher, then your diameter would be the square root of ( (0.5)^2 + (0.0005)^2 ) or 0.50000025".  As my dad would have said, "good enough for the girls we go with".

Bruce


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## TonyBen (May 28, 2019)

BGHansen said:


> Boy, sure seems like for hobby stuff that 0.0005" would be close enough.  Anything tighter than that practically gets into "the Emperor's New Clothes" realm.  Not many of us here working on parts for the space shuttle.  Depends on your projects.
> 
> Titanium Knurler (pretty sure) did the math on the effective diameter difference when cutting with a vertical offset on the tail stock.  It varies based on the diameter, but it's practically im-measureable for a 1" diameter turning.
> 
> ...


He’s talking about the runout on the cut I did at the chuck. I cut it down to the tailstock diameter and threw a dial indicator on it. As I turned the chuck by hand, I got a o.0005” runout. 

I probably should lock the cross slide and try again. 

Tony.


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## kb58 (May 28, 2019)

If you're happy with it, you're already done.


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## pdentrem (May 28, 2019)

Thermal expansion of the metal while doing the cut would easily account for that tiny movement. Even push back against the tool would do the same. I would call it done, as well.


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## TonyBen (May 28, 2019)

I went back over lunch and locked the cross slide. I got the runout down to maybe 0.0002", but that could be from a sloppy cut on my part. I'm not experienced enough yet to make a clean cut. I'm sure my cutter angle and feed rate are all wrong.

Thanks to all who have helped!

Tony.


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## brino (May 29, 2019)

TonyBen said:


> I got the runout down to maybe 0.0002", but that could be from a sloppy cut on my part. I'm not experienced enough yet to make a clean cut. I'm sure my cutter angle and feed rate are all wrong.



two tenths runout? 
can't be too much you're doing wrong!

-brino


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## TonyBen (May 29, 2019)

Thanks! What I mean, also is that when I turn the chuck by hand, the needle dances as I turn it, but as soon as I take my hand off the chuck, the needle settles around 0.0002" from zero from all positions. Had the cut been cleaner, the needle may not have been dancing up and down.

Tony.


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## TonyBen (Jun 2, 2019)

I rebuilt and re-lubed my scroll chuck today. I took a reading on the backplate and it had 0.010" runout. I was about to face it but decided to check the spindle. I found out the runout was in a spacer in the spindle.












I've got to see if I can mill it flat or have my buddy have it precision ground.

Tony.


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## TonyBen (Jun 3, 2019)

Well I managed to mill the high spots down to within about about 0.002" and runout on the 3-jaw is about 0.004" on a 1" thick bar. Before I milled the spacer, chuck runout was 0.023" on the same bar. At least for now, I can make bedding pillars with the 3-jaw. My 4-jaw won't clamp down far enough.

Tony.


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## markba633csi (Jun 3, 2019)

I wonder if that spacer is a factory part? It's unusual to have that
Mark


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## Dabbler (Jun 3, 2019)

I've not had that part on my machine. What is under it?  What are the dimensions?  Could it have been a previous owner's weird adaptation that wasn't working? (humm)....  I'll go an measure my spindle later today and post my results....


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## TakeDeadAim (Jun 3, 2019)

The .0002" runout you are seeing could likely be from your indicator set up.  Unless you have something really quite solid its easy to have that much movement, the kant-twist clamp to the height gauge, if thats what your using could be the issue or simply the height gauge is not sitting fully flat on the cross slide.   Just for fun, take your finger and very very lightly tap the base while the indicator is touching the part.

Im in agreement with Dabbler on the chuck/spindle spacer.  Ive not seen one on any machine.  Checking the spindle runout is easy enough to do; post the results when you do check it.


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## TonyBen (Jun 3, 2019)

The shoulder on the 3-jaw chuck will not screw on far enough to make contact with the spindle shoulder. It will screw on far enough to contact the spacer. Maybe the spacer was meant to make the 3 jaw work with the lathe. I haven’t tried to screw on the 4-jaw without the spacer. 

When I received the lathe it had the 3-jaw installed. 

Tony.


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## TakeDeadAim (Jun 3, 2019)

I understand why its there, what I think Dabbler and I are saying is that the presence of a spacer in that location is unusual and suggests some investigation might help.   If your going to use the machine for barrel work I have had good success with a set-tru type 3 jaw.   My lathe came with a spider on the back of the spindle so I did not need to add one.  I learned from Charlie Milazzo many years ago and am only a few miles from Krieger Barrels.


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## TonyBen (Jun 3, 2019)

Cool. I love their barrels. I’m just waiting on a bolt to install one on an M14 build in the shop. 

My friend told me to bring the spacer to his shop this evening and he’s going to surface grind it. I showed him pictures this morning. 

Tony.


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## pdentrem (Jun 3, 2019)

I would compare the backing plates and see whether the 3 jaw matches the 4 jaw. The spacer is a bandaid.


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## TakeDeadAim (Jun 3, 2019)

They make very hight quality parts as does Wisconsin Trigger.  Happy to have them in our state.  If you grind it will be parallel, still odd to see that in there


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## Dabbler (Jun 3, 2019)

Tony, I'm pretty sure that the 3 jaw setup with the spacer is a weird accomodation done by a hobby machinist.  but here's an idea:  When you are ready, bore out the adapter (if there are enough threads)  to allow the adapter to contact the actual flange on the spindle.  Both my chucks mount this way, and it is a very solid technique.  I think you lose a _little _having the spacer there, in terms of the idea that more parts makes less rigidity and more error....


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## TakeDeadAim (Jun 3, 2019)

Dabbler,   I totally agree,  There is a reason virtually all the high precision lathes lock up against a taper.  Next best thing is to have the chuck pull snug against a shoulder.


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## TonyBen (Jun 3, 2019)

Man, talk about baptism by fire. I'm definitely learning about lathes the hard way. If it were easy from the start, I probably wouldn't learn so much.

I'll measure the spindle thread length and distance from face to shoulder and take the spacer and chuck to my friend with the surface grinder. He's got a few lathes, mills and a couple of CNC machines but he's terribly busy all the time.

I tried to guilt him into swinging by my house today to at least look at my lathe in person. He was telling me he's got a fourth lathe that's new and never used that he's setting up this week. maybe he can use one of them to extend the threads in the backplate if needed or if possible. He also said he may need to cut some threads out of the backplate to extend the shoulder so that the spacer won't be needed which is what I think Dabbler is saying above.

He was also mentioning turning a 2" piece of steel on a lathe to true it up and then chuck up my 3-jaw chuck to the piece while its installed on his lathe and then facing the back shoulder of the backplate to true it up so that when its installed on my chuck it will already be trued.

You all have been great. Again, thanks.

Tony.


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## TonyBen (Jun 4, 2019)

So my friend actually came over yesterday and looked at my equipment. We placed the chucks side x side and the 4-jaw has more relief and I actually was able to screw it all the way on and it hits the spindle shoulder without the spacer. The 3-jaw had about 0.200" less relief. He told me what to do to fix it. He checked the depth to make sure that if I cut deep enough that the spindle won't bottom out inside the 3-jaw and we have ample clearance.

3-jaw on the left, 4-jaw on the right...






4-jaw...





3-jaw...





I reversed the jaws on the 4-jaw and chucked up the backplate and used a carbide boring bit to remove a bunch of thread. I stopped just a little short.





I still have to take another 0.040" before it will contact the spindle shoulder. I'll finish that up tonight.





This is the first time I've ever used a boring bit. I used a cheap Chinese carbide boring bit I bought 2 weeks ago. I was getting a bit of chatter and it really squeals. I was using Mic-O-Cut cutting fluid. Maybe I was just going too slow. I haven't cut any of my high speed steel blanks yet to make a HSS boring bit.

Tony.


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## Dabbler (Jun 4, 2019)

When boring cast iron, it is best to not use any cutting fluid. It was squealing because your RPMs are too high, and your bar is made of Swiss cheese.  I'd try about 360 RPM (or slower), and take .010 cuts.  Also the geometry of the carbide can make chatter worse.  The target should be a slip fit - .001 or less larger than the diameter of the non threaded part of the spindle.


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## TonyBen (Jun 4, 2019)

Thanks. I was using the Chinese version of the short fat bit shown on the front row, far right.



I basically just skimmed the surface and kept it going. Actually, at first, what I took off was smaller in diameter than the original freebore. After I got my desired depth, I blended it in with the original inside diameter.

Tony.


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## TonyBen (Jun 4, 2019)

That’s it! I give up on this chuck! I got it all the way against the spindle but only 75% of it is contacting the spindle. I faced the backplate rim and runout went from 0.003” to 0.010” on a 1” thick bar.


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## pdentrem (Jun 4, 2019)

You now have to reface the mounting surface for the chuck. By machining the back the front is no longer perpendicular to the spindle. There are quite a few posting here on machining the plate. I posted one a few years ago on making two backing plates.









						Making a couple of threaded spindle backing plates for my lathe
					

When I sold my Atlas 10F24, I held on to my Bison 5” 3J, as it was fairly new. Naturally I needed to make a new backing plate to mount it onto the new lathe. The old plate was 1 1/2” X 8 while the new spindle is 2 1/4” X 8, so I needed new metal to do this. I recently purchased 2 backing plates...




					www.hobby-machinist.com


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