# Starting Mini-Lathe Mods



## cfellows

The adventure begins. I'm starting on a George Carlson quick change toolpost. It uses a 1" diameter round post to support the tool holders. A tangential clamping screw holds the toolholder in position on the post.  This is a link to some pictures of this QCTP.

http://homepage.mac.com/bhagenbuch/machine/pages/freeby.html

I chose this design because it's takes up little real estate on the cross slide and is pretty simple to make tool holders for. I've removed the compound from my lathe because I don't use it very often. By attaching the toolpost directly to the cross slide, I will have greater rigidity and fewer places for things to move where I don't want them to. Anyway, it just removes a lot of clutter from a pretty small space.

Here's the beginning. I turned it from a 3" long, 2" diameter steel rod. I offset the column from the center of the base so there would be room for the screws that attach it to the cross slide.












Chuck


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## Twmaster

That's a neat looking project Chuck.

Removing the compound does take a ton of slop out of that machine.

If you feel up to it I'd recommend lapping the slides on the compound and cross slide, check the straightness of the gibs and toss those silly carriage retainer system and replace the ridiculous jack screws in those plate with shims.

That will take nearly all of the slop out of the carriage.

Also, it's important you get a good carriage lock.

I did the above carriage mods to my 7x lathe and it made a huge difference. Night and day. I'd be happy to detail how at some point if you'd like.



Lastly. Make sure the carriage is sitting flat on the ways.


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## Blogwitch

Chuck,

I don't know how you feel about doing surgery to your lathe, but I did a large rescue to a really poorly one.

http://madmodder.net/index.php?topic=627.0

Yours should be nowhere near as bad as that, but I would thoroughly recommend doing the tapered gib mod, it totally transforms the running and rigidity of the machine.

Also, a little further into the post, 

http://madmodder.net/index.php?topic=627.msg5085#msg5085

it shows how I did a quickie saddle clamp using just a brass ended bolt. The way they come from retailers who market such things, they are a rather bad design, and will still allow a little movement under heavy cutting. The way I designed mine, it locks it up solid and doesn't get in the way of anything.

It might be worth a little troll thru to see if it gives you a few pointers.

Bogs


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## Twmaster

John, (With apologies to Chuck for a small hijack)

I found your post on Mad Modder about fixing Darren's lathe. What a terrific job. I was fortunate that the work I did to my old 7x took just about all the slop out. If I had a bigger mill I'd have gone about that as you did. Nice work!


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## cfellows

Mike, thanks for the comments and the suggestions. 

John, I had seen the thread on MadModder where you had rebuilt Darren's 7 x 12. I'm not at all afraid of surgery and will be doing a few things as time permits. First thing is a decent tool post. I've also discovered a problem with High / Low range lever. It doesn't shift complete into high gear and will pop out of gear under the slightest load. I will also be doing some work on the carriage. It's a little tight right now and I like the idea of the taper gibs, although anything involving tapers tends to make me break out in a cold sweat.

I plan to use this lathe mostly for small, precision work. A lot of operations will involve drilling from the tailstock so that will no doubt require some attention and tuning. I also need to find a good drill chuck and short MT2. I like the keyless chucks, but they tend to be kind of long so I might go with a 1/4 or 3/8 Jacobs.

I also want to make an ER collet chuck for the spindle. I have an ER40 set so I may go with that. Or something smaller if that turns out to be too big.

Chuck


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## cfellows

Got my first tool holder made for the new tool post. It's a tangential cutter which uses a 1/4" bit. It started out as a 2" long piece of 1 1/2" x 1" cold rolled steel. The front is milled to a 12 degree angle, then the 1/4" wide slot is milled at a 12 degree angle to the side. The tool bit is ground at a 30 degree angle as measured diagonally across opposite corners. The bit needs further sharpening, but it cuts brass real good as it is.





















I need to add a height adjustment stud and nut which will reference against the top of the post, like the Aloris style.

Chuck


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## Blogwitch

Chuck,

I wasn't implying you go that heavy route, just trying to maybe help a little.

With regards to the tapered gibs. Reading between the lines on a few sites and write ups about them, it seems that a few people have just gone ahead with the mod, without first checking the main casting out, and they are still getting the same sorts of problems they were having before doing it. So it isn't the cure all that everyone thinks. It needs to be a combination of things to be checked and done.

So if you did want to go that route, make sure you check out the main casting first, as I did.

I have done a couple of main bed true ups since doing that Darren post, one was only out by about 0.0015" and didn't really need doing, but he insisted I got it as good as humanly possible, so I machined it up, the other one did need it, it was about 0.006" difference in thicknesses along the bed, so really, it seems that it is pot luck as to whether you have a good enough casting or not to do the tapered gib mod, without first machining the bed to a good degree of accuracy.

As you may have noticed in that post, I showed a very easy way to get perfectly matching tapers, and I can assure you, it really is nothing to sweat over. Once you have the basic one cut, all others just drop into place using the basic one as a template and guide for machining.

I know exactly what you mean about the length of keyless chucks, and I can imagine it could cause a bit of a problem on a smaller machine, but now having gone over almost completely to keyless now (only my tapping stand has a 1/4" Jacobs keyed one, plus some of my air tools), I find them very robust and accurate. 

But what would the world be like if we all used exactly the same tooling and methods, very boring. 

Everyone to his own.

I have been pondering over whether to make one of those 'diamond' cutters for a while now, and seeing as to how you have made such a good job of yours, I might ponder it over a little more, for when I have some time on my hands. Rof} Rof} Rof}

John


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## cfellows

Thanks for the info, John. I will be approaching all upgrades and tuning cautiously and as needed. I also want to take of items which might become problematic soon and/or accelerate wear. I've read that the socket head cap screws used to hold the carriage clamps in place should be replaced with studs and nuts since the screws don't thread in very far and tend to wear quickly. 

I really need to look over the lathe pretty well and get familiar with all it's little vagaries.

Chuck


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## Tin Falcon

IMHO a cover for the apron gears is a must. just about any material will work. Plexiglas, poly carbonate. ,aluminum or steel. I used aluminum. I keep wanting to do a cam lock for the tail stock but have not yet another is the saddle lock . 
Tin


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## BobWarfield

Lots of cool mods can be done to lathes. I like your QCTP, Chuck! 

Let us know how that tangential holder works out for you too.

Bogs, I had missed your tapered gib conversion and enjoyed going back to see it. I would think it would be straightforward to add a very convenient saddle lock to such an arrangement. My RF-45 mill has tapered gibs and the locks work by applying additional pressure to the side of the gib. Seems like you could come in from the front of the apron and do a very nice job of that.

Long ago in a galaxy far away I started to make a lock that never got finished:

http://www.cnccookbook.com/MTLatheSaddleLock.htm

It had considerable holding force due to the combined leverage of a screw and the lever lock itself. I just needed to bolt it to the carriage, but ultimately lost interest. That's a less intrusive way to go. In retrospect, I should have completed it as I have reached for Ye Olde Wrenche many times before parting.

Cheers,

BW


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## Twmaster

Chuck,

That post and holder came out very nicely done.


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## cfellows

Thx, Tin. The apron gear cover is on the list of things to do.

Thx, Bob. This minilathe is almost like a candy store with the number of mods and improvements that are shared on the WEB. I might spend the rest of my machining career tricking out this minilathe!  :big:

Thx, TWMaster. Appreciate the comments.

Here are some pictures of the jig I made for grinding tool bits for the tangential holder. It's made from a hunk of aluminum to help conduct heat away from the tool bit. I use the jig with my 2" x 48" vertical belt sander. Cuts fast and relatively cool. 
















Chuck


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## cfellows

I decided to have a look beneath the covers at my new HF Mini Lathe today. No real surprises. Found where some of the red paint had bled under the carriage where it was riding on the ways and cleaned it off. The good news is that the carriage does fit flat on the ways. However, as Bogs and others have stated, the clamping system leaves a lot to be desired. So, I've decided to go ahead with the tapered gibs modification that was described on mini-lathe.com and also documented by Bogs on Mad Modder.

I plan to use 1/2" x 3/4" x 4" long aluminum for the clamps and 1/4" thick brass for tapered gibs. I'm also going to try this without the taper jig. Positioning the clamp in my milling vise pretty accurately at 1 degree will be pretty easy. Then, I'll used the milled clamp as the jig to taper the gib. 

I also ordered a wilton, 5/16" keyless drill chuck with an integrated #2 morse taper shank. I will have to shorten the taper, but this chuck is noticeably shorter than typical keyless chucks and is advertised at .0019" runout, so I think it will work well for this lathe.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360240116150&ssPageName=STRK:MEWAX:IT

Chuck


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## itowbig

i like those tool holders very simple and they work. i made something similar but i like your tool holders better. :bow:


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## cfellows

I'm getting along pretty well with my tapered gib upgrade. I'll post the last picture first so you can see what I'm trying to get to.






The clamps are made from 1/2 x 3/4 inch aluminum 4 inches long. The next picture shows me milling out the side where the brass gib will fit. I've lifted one end of the clamp and propped it up with a 1/16" thick piece of aluminum to create the angle. Should be somewhere around 1 degree, although the exact angle isn't critical. Here you see the first pass removing .050".






In the next picture, I've finished the clamp and am using it as a base to hold the brass gib while I mill it. By using the clamp as the base, I am ensuring that the gib taper will exactly match the clamp taper. Note that I've removed the 1/16" piece of aluminum and mounted the clamp in the vise with the base flat.






Despite my initial misgivings, I have to say that so far this project has been a piece of cake.

Chuck


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## Swarf Rat

This is an interesting thread. I think it's funny how modifying a Chinese lathe seems so natural while American iron generally seems more sacred.


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## cfellows

Swarf Rat  said:
			
		

> This is an interesting thread. I think it's funny how modifying a Chinese lathe seems so natural while American iron generally seems more sacred.



Yeah, I think it's been said many times that the chinese equipment represents a diamond in the rough and with a little work, can be made into a pretty respectable machine. The American iron isn't without it's faults since it's usually old, typically well worn, and occasionally abused. I bought an 11" Logan lathe a number of years ago. I had to have the bed reground, replaced the headstock bearings, most of the bushings in the gear train, and several of the gears. Also, the back gears had damaged teeth and I never did get those replaced or adequately repaired. However, having said all that, there's no doubt in my mind that back in 1952, that Logan lathe came from the factory ready to work with no mods or upgrades.

Chuck


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## Twmaster

Chuck,

That set of gibs is looking good. Almost seems too easy. I'll be watching.


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## cfellows

Thx, TWMaster. Yes, I've been pleasantly surprised at how smoothly this has gone.

Finished up the tapered GIBS today. Here's some pictures of some of the steps.

I liked the rounded cut-out Bogs did for the carriage drive pinion on the front carriage clamp. I didn't have a ball nose mill of the right diameter, so I put the clamp in my milling vise sideways and used a 3/4" end mill to cut the rounded grove from the side. Worked great!






Came time to make the adjusting screws and rather than make them from scratch, I used 6-32 socket head cap screws and pressed a small steel disk on the head of each.






First I chucked up some 3/8" solid rod and bored out a small length on the end about .004" smaller than the SHCS head.






Next I cut of a piece a little longer than the depth of the screw head.






Here I've got the screw mounted on the side of my little palmgren 1 1/2" toolmakers vise. The assembly is ready to go to press, uhhh, my 20 ton hydraulic press. I know 20 ton is a bit excessive, but I don't like to leave things to chance...






Here I've got the pressed-together assembly in the lathe, ready to true it up and trim it back to the right thickness, about .1".











And finally, here are the front and rear, respectively, gibs in place on the lathe carriage. As Bogs would say, it works a treat, very smooth and easy movement with no detectable play at all. I'm very pleased with the way this turned out and, as I said before, how easy it turned out to be.

Chuck


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## Deanofid

Looks like a clean and effective setup, Chuck. Well done.



> ..my 20 ton hydraulic press..



No one will ever accuse you of pussyfooting around. You don't need a 16 lb hammer when you have one of those things. 
A man should be decisive! ; )

Dean


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## ozzie46

Chuck, thanks for the gib write up. I've been meaning to do this for several years now but have been intimidated by it. Now I will give it a shot as soon as I can make time. 
 Thanks again.


 Ron


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## Twmaster

Chuck, that has come out very well. Bravo. Applause for YOU!


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## Blogwitch

Very nicely done Chuck, and a very good result. It looks like you had a lot less trouble than I did. 
I gather you like the smooth action and easy adjustment over the old method.

I have to agree with you on how easily it can be done, I reckoned on a good day or maybe two in the shop if everything with the machine was OK. 

BTW, great fix on the adjusting screws, I had a crap time trying to make the slots strong enough for adjustment, your method completely solves that.

But if anyone is going to try this, give it a good measure up and check for squareness before you start to hack away. You must watch out for things that are out of line or bent if you have an older type of machine.

Some of those early ones were made by cavemen with flint tools.


Bogs


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## Twmaster

*Some of those early ones were made by cavemen with flint tools.*

The ones as of 2008 were as well in some instances...

Chuck, after looking over your gibs again I have to say that hands down this is way better than the route I took with shimming my old 7x10 lathe. I cannot see this taking any more time than I spent fussing with making shims.

Between your posts and Bog's thread over on MM I think anybody with a mill can make these. 

One last silly question. (The tool geek in me wants to know) what milling machine do you have?

Thanks!


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## cfellows

Bogstandard  said:
			
		

> Very nicely done Chuck, and a very good result. It looks like you had a lot less trouble than I did.
> I gather you like the smooth action and easy adjustment over the old method.
> 
> I have to agree with you on how easily it can be done, I reckoned on a good day or maybe two in the shop if everything with the machine was OK.
> 
> BTW, great fix on the adjusting screws, I had a crap time trying to make the slots strong enough for adjustment, your method completely solves that.
> 
> But if anyone is going to try this, give it a good measure up and check for squareness before you start to hack away. You must watch out for things that are out of line or bent if you have an older type of machine.
> 
> Some of those early ones were made by cavemen with flint tools.
> 
> Bogs



Yep, Bogs, I'm definitely pleased with the results. I still have a bit of stickiness to iron out. The ways might be a smidge thicker toward the tailstock end. May not be able to do anything about that. Also, the plastic cover I installed on the inside of the carriage apron rubs a little bit against the carriage feed gears. I may just face off the gears a bit to sort that out. Seems easier than making a gasket to raise the cover off the casting. Also, the front gib may be rubbing against the rack for the carriage feed, so I need to check that out. All minor things that I should be able clean up.



			
				Twmaster  said:
			
		

> *Some of those early ones were made by cavemen with flint tools.*
> 
> The ones as of 2008 were as well in some instances...
> 
> Chuck, after looking over your gibs again I have to say that hands down this is way better than the route I took with shimming my old 7x10 lathe. I cannot see this taking any more time than I spent fussing with making shims.
> 
> Between your posts and Bog's thread over on MM I think anybody with a mill can make these.
> 
> One last silly question. (The tool geek in me wants to know) what milling machine do you have?
> 
> Thanks!



My mill is an Enco mill/drill that I bought about 16 years ago. It works good and I can't afford / don't have room for a bigger one. Besides,it hard to sneak those really big items past the CFO.

Chuck


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## cfellows

One more follow up on the tapered gibs.  I found a couple of problems and fixed them.

The first problem I found was a small ridge on the bottom of the rear way where it meets the vertical part of the casting. The top, inner edge of the gib was riding on that ridge. I fixed that problem by milling a groove along the edge of the gib. In woodworking, we call that a rabbet... not sure what the metalworking term is.






When I put it back together, I found that the gib was now too thin. So, to correct that without making a new gib, I skimmed about 7 thou off the top of the clamp where it meets the carriage. 






The other problem was not enough clearance between the rack and the carriage feed pinion. So, after pondering that for a bit, I decided the easiest fix would be a shim between the carriage and the apron. You can see the end of the brass shim sticking out in the following picture:






Note to self: Wonder how many times I'll cut myself on that little piece of shim before I decide to trim it off?  :-\

Chuck


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## Twmaster

Chuck,

Not bad if that's all you've had for follow-on fixups. I see a lot of folks with those older Enco Rong-Fu clone mill-drills. I'm hoping to be able to afford something similar this summer. Not a matter of getting it past the CFO. More a matter of getting it past an empty wallet.

And my guess is 6 on the number of times you knick yourself on that brass!


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## zeeprogrammer

I'll take 2.

First time..."Drat...I knew that was going to happen."
Second time..."Drat...Not going to let that happen again."

No one should admit to more than that. ;D


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## cfellows

zeeprogrammer  said:
			
		

> I'll take 2.
> 
> First time..."Drat...I knew that was going to happen."
> Second time..."Drat...Not going to let that happen again."
> 
> No one should admit to more than that. ;D



Actually, having already seen it and commenting on it, I would be thoroughly embarrassed to admit it if I cut myself on it now. Guess I better go trim it off!

Chuck


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## Swarf Rat

Chuck, I really like those big-headed gib adjustment screws. I wonder if they'll need some kind of lock to keep them from vibrating out of position.

Cool idea to shim the apron to fix the pinion clearance. Does that not affect the half-nut allignment or pinion engagement?


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## cfellows

Swarf Rat  said:
			
		

> Chuck, I really like those big-headed gib adjustment screws. I wonder if they'll need some kind of lock to keep them from vibrating out of position.
> 
> Cool idea to shim the apron to fix the pinion clearance. Does that not affect the half-nut allignment or pinion engagement?



I hope not. I haven't installed the lead screw after shimming up the apron. With a little luck, the .010" shim won't seriously affect leadscrew alignment. I'm not too concerned about it at this point since I doubt I will be using the leadscrew much.

One other issue I had to correct is that the tapped holes for the screws that hold the rack onto the bed aren't deep enough. The result is that 1) the rack isn't held on very tight and 2) the heads of the screws stick out proud of the rack. My quick fix was to grind off the length of the screws a little bit. The holes could be drilled deeper, but I don't have any metric taps to deepen the thread.


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## Twmaster

Chuck,

You may want to go ahead and replace the hardware holding the rack to the bed. On the 7x10 I had one of the screws was stripped. I drilled the hole out and tapped to the next size up. I cannot remember what size I used and the lathe is long-gone.


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## ozzie46

Cfelloows, How will the shim effect the mesh of the rack and the saddle gears? It seems to me you have introduced .010 free play between the gears. Maybe it won't effect anything.

  Ron


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## cfellows

ozzie46  said:
			
		

> Cfelloows, How will the shim effect the mesh of the rack and the saddle gears? It seems to me you have introduced .010 free play between the gears. Maybe it won't effect anything.
> 
> Ron



The purpose of the shim was to add some clearance between the rack and the saddle gears. They were too tight before but after adding the shim, they work more smoothly now. I'm actually thinking it may need even more. It's not binding now, but I think the gears could use a little more clearance.

Chuck


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## ozzie46

Thats good news Chuck. Sounds like it work out very well.

 Ron


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## cfellows

This is a picture of a 3", 3-jaw chuck I bought several years ago. I don't recall why I bought it, other than I just thought it was neat, but I haven't really found a use for it until now. Turns out it is virtually identical to the 3" chuck that came on my Mini-Lathe.

So, I chucked it up in my 8", 4-jaw in my logan and trued up the back of it. Then I bored out the recess to about .030" oversize. Didn't mean to go that far, but it kind of got away from me. Anyway, now I am going to make it into my version of an Adjust-tru chuck so I'll be able to adjust for the runout. Should be about the simplest way to get a really accurate, self centering holding device for the mini-lathe.






Chuck


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## cfellows

My Wilton, keyless chuck with integrated MT2 shank came in todo. This is really a nice little drill chuck, even though it was kind of pricey at $62, but shipping was free. Here's a picture compared to my 3/8" generic keyless chuck that I use on my Logan. The overall length of the chuck body on the Wilton (bottom) is almost 3/4" shorter than the generic keyless. That's going to be important on the mini-lathe. Hate to chop off the shank, but gotta shorten it to make it fit the tailstock on the mini-lathe.


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## cfellows

One more post for today. Here is the 3-jaw chuck with the adjusting ring added. I turned the ring out of a piece of steel pipe with a 1/4" thick wall. The ID was turned about .010" smaller than the chuck then pressed on with my (you guessed it) 20 ton hydraulic press. Really had to work that sucker to get it pressed on. Probably should have heated the ring up first. After I got the ring on, I mounted the chuck in my 8" 4-jaw chuck on the Logan, centered it up really good, then trimmed up the ring and bored out the inside to about .030" larger than the spindle flange on the mini-lathe. Tomorrow, I will drill and tap 4, equally spaced radial holes around the exposed part of the ring on the chuck to bear against the outer diameter of the spindle flange for centering the chuck. Once centered, the chuck can be tightened against the spindle flange with mounting studs and nuts. I don't expect to change chucks often if at all, so re-centering should only be an occasional effort.











Chuck


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## cfellows

One more post for this part of the project. I finished my version of the set-tru 3-jaw chuck and installed it on the lathe. I drilled and tapped 4, equally spaced radial holes around the outside of the adjustment ring. 8-32 setscrews were threaded into each hole after grinding the ends flat so they wouldn't dig into the lathe spindle flange. The chuck was mounted on the lathe using the usual studs and nuts provided with the lathe. These were tightened moderately, then the 4 set screws were used to center the chuck, using a DTI and a round bar chucked in the lathe. When the bar was accurately centered, the nuts holding the chuck were then further tightened. I consider this a complete success although we'll have to see how well work of different diameters stays centered.

In this picture, you can see one of the 4 setscrews.


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## cfellows

Don't ya just love the look of a freshly made dovetail slide? 






Decided I needed the ability to cut angles on my minilathe so I decided to think outside of the box (some might say outside of the planet). Rather than attach the tool post to the compound, I decided to make a compound which attaches to the toolpost. Here is the first piece. The compound will slide horizontally on the dovetail that I've already finished. Next is the part that slides.

Chuck


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## cfellows

Nearly finished with my toolpost compound. I decided to make a toolholder which takes a standard carbide insert. I still have to make the clamp and screw to hold the insert down and I have to make or buy a more suitable handwheel. Finally, I need to add the height adjustment stud and nut. It looks like I'll also have to mill some off the bottom of my tool post since the insert needs a little more vertical adjustment room.

















The overall travel is 1.25". Think this will be perfect for cutting valve faces and other angular turnings.

Chuck


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## zeeprogrammer

Watching with interest Chuck.
That looks nice. With my limited experienced I've had decent luck with carbide inserts.


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## alcostich

Chuck,

Any chance you could give some dimensions for the jig for the tangential tool bit jig?
Thanks.

Alan

Here are some pictures of the jig I made for grinding tool bits for the tangential holder. It's made from a hunk of aluminum to help conduct heat away from the tool bit. I use the jig with my 2" x 48" vertical belt sander. Cuts fast and relatively cool.


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## Blogwitch

Chuck,

All this lot is great work on your part, very professional looking. But I would like to transport you back a few posts to your leadscrew.

Have no worries about it, it is very easy to adjust to getting it to run true to your saddle and bed.

Start at the tailstock end, engage the half nuts, insert screws and tighten up the leadscrew block. Release half nuts, go as far as you can towards the headstock, slacken off the bolts holding the gear train to machine, engage the half nuts, tighten up the loosened screws.

Repeat once more at both ends, and you should find the leadscrew will be centralised as good as you are ever going to get it. You might need to shim up the blocks if it pulls towards the casting, but the way it is made, there is plenty of adjustment built into these machines to get you out of trouble.

With a little work, these machines can be turned into very accurate and robust machines for very little extra outlay, and if ever I had the requirement for one, I would have no qualms about buying one and giving it a good dose of looking at, just as you are doing. 

John


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## cfellows

Here's a drawing of my tangential tool sharpening jig. The only critical dimension is the 60 degree angle.






Chuck


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## RollaJohn

Chuck

I am interested in your Wilton keyless chuck with the Morse Taper arbor. How is it working out for you? 

I just looked at your eBay seller's listing and it is still available. It has come down in price to $29.99 with free shipping but I see that you evidently are the only person who has purchased the item. At least the seller claims to have sold only one.

So it is up to you to let us know: Is this a good item or should we save our money for something better? You have the power!!


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## cfellows

Well, the Wilton chuck hasn't seen a lot of use, but it seems very well made. The action is tight but smooth and easy. I thought it was a good buy at $60+. At $29 it seems like a screamin' deal!

Chuck


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## Omnimill

cfellows  said:
			
		

> Thx, Tin. The apron gear cover is on the list of things to do.
> 
> Thx, Bob. This minilathe is almost like a candy store with the number of mods and improvements that are shared on the WEB. I might spend the rest of my machining career tricking out this minilathe!  :big:
> 
> Thx, TWMaster. Appreciate the comments.
> 
> Here are some pictures of the jig I made for grinding tool bits for the tangential holder. It's made from a hunk of aluminum to help conduct heat away from the tool bit. I use the jig with my 2" x 48" vertical belt sander. Cuts fast and relatively cool.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Chuck



Chuck, what angle have you used for your grinding jig?

Vic.

Update, Oops sorry just seen the plan!


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## cfellows

Well, I think I'm now an official hoarder of projects. I ordered a 14" mini-lathe bed conversion kit from LMS and it arrived via UPS a few days ago. Tonight I tore down the 10" version and will now reassemble with the new bed. I was pleased to discover that the saddle fit the ways on the new bed perfectly with no adjustment to the gibs. How lucky was that! On the other hand, the long vertical slots for the motor mounting studs are completely missing. May have to look at an alternative motor mount. Might consider putting in an intermediate jackshaft for more high / low control. We'll see.











Has anyone else completed this conversion?

Chuck


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## winklmj

cfellows  said:
			
		

> On the other hand, the long vertical slots for the motor mounting studs are completely missing.



If you dont' go the jack-shaft route, there's some info on the web about using a heavy-duty gate-hinge for a pivoting motor mount.


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## cfellows

I followed up on the gate hinge idea and determined how the original motor mount is supposed to work. So I spent an hour or two coming up with my own version using a door hinge:






After finishing it up I decided to go ahead and mount the rack. I opened up the big plastic bag that came with the lathe bed conversion kit and, guess what, they had included a motor mount that goes with the 14" bed! And here it is, affixed to the motor.






So a couple of wasted hours, but problem solved in a much more elegant manner. Guess I should have checked the contents of the kit more closely before starting, but what fun would that be!

Chuck


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## Blogwitch

I've done my fair share of trash can diving after inadvertently throwing away supplied bits.

But I still do it, rip the packaging apart before first getting out and reading the destructions.

This looks like it is really going to improve your little mini lathe.


John


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## cfellows

Thx for dropping in, Bogs. I'm not really sure why I'm fussing with this mini lathe. I have an 11" Logan which is in good shape and will do pretty much anything I ask of it. However, I have already found that having a second lathe set up can come in handy when you don't want to disturb the set up on the other lathe for some reason. Also, if I have to downsize my shop even more as I get older, I would like a decent smaller lathe. I've ordered the metal high / low gear and the tapered roller bearing set for the spindle. After I get those installed I think it will be in pretty good shape, except for some other add-ons like a carriage lock, carriage stop, etc.

Chuck


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## Blogwitch

Chuck,

After I had finished Darren's lathe, I couldn't, in all honesty, believe how good it ended up, and I am sure yours will end up just as good, if not better.

If I hadn't have just picked up the Pultra to refurbish, I was considering buying a smaller lathe, purely because of the reasons you mentioned, and it would have been a mini lathe. With a bit of care, they can turn out to be an outstanding bit of kit.


John


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## kc5ezc

Chuck: I bought a HF mini-lathe 6 years ago. Found it to be a little short in the bed area, so ordered the 12 inch mod from LMS. The 14 inch did not exist or I would have got it. Then bought a 13x40 from Wholesale tools. The mini-lathe is a work in progress; always something that I can do to improve it a little bit. The WT lathe hasn't had to have any mods to it. I really enjoy having the two lathes. The mini-lathe is great for the small stuff and the larger one takes care of the big, tough stuff. Big to me anyway. Thanks for the tapered gibs write-up. That is next.
John Burchett
in Byng OK


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## rcmadness

I started with the 7 x 10 myself about 10 yrs ago. It has served me well. I bought the 10 x 22 over the summer and bigger is nicer but I still have my 7x10 setting next to it. I use it mostly for quick cuts and polishing. The variable speed is what draws me to it, when I want to buff something out I have a buffing wheel that chucks up and a plastic bed cover that makes it a great too to spin up the buffing wheel. I doubt I will do any more mods to it, I am now tinkering with the big lathe.

Your gib makeover is great and I actually thought about trying it on mine. That is the one thing that bugs me about Chinese equipment is the fact I cannot keep things tight on anything Chinese I own. Lathes, mill, drill presses etc, everything tends to loosen up quickly.

I headed down to ace hardware tomorrow to find some american made 6 mm set screws to replace all the set screws in my Chinese tool holders. I stripped another one out tonight.


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## cfellows

Thanks for the comments guys. I've had a bunch of projects underway lately and haven't felt like any of them will ever get finished. However, today I am nearly finished with the list of outstanding mods to the mini lathe. I am (mostly) finished with the 14" bed conversion. I still have to drill and tap a few screws that hold guards and covers on. I also have to drill and tap the hole for the change gear banjo, but there's no hurry on that since I doubt I'll be doing threading any time soon. 

I also replaced the plastic speed change gear on the spindle with a metal one. I left the intermediate plastic speed change gear installed so the lathe would run quieter, and, if something is going to fail, I'd rather it was the intermediate gear and not the spindle gear. 

Finally, I replaced the spindle ball bearings with tapered roller bearings. After getting it all back together, I found a plastic spacer lying on the workbench that belongs on the spindle inside the headstock. That's it sitting on top of the headstock casting. Its purpose is to keep the spindle speed change gear positioned properly. Oh, well, tomorrow I'll get the spacer put back in its proper place, then the new spindle bearing job will be completely finished. The spindle rotation is very smooth and the total inidicated run out eight inches out from the chuck is about .001". At this point, I'm very happy with the outcome of all these changes.

Unfortunately, I didn't photogaph any of the process, but will answer questions for anyone thinking about the same conversion.






Chuck


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## cfellows

This is a crank I made for the leadscrew on my 7 x 14. I didn't want to modify the leadscrew, so I mounted the crank on the left side of the leadscrew. I made the crank from 1/4" thick aluminum and attached it to a 42 tooth browning timing pulley. 






At some point, I will lash up a DC gear motor connected with a removable timing belt so I can also have a variable speed carriage feed. I don't expect, at this point to use the change gears very often, although I can easily remove the crank and revert to the change gears if need be.

In this picture, you can see a steel ring which was heat shrunk on to the hub of the gear. This will be engraved with graduations and numbers for a fine feed measurement.






Chuck


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## Maryak

Neat Idea Chuck :bow: :bow:

Best Regards
Bob


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## cfellows

Added another tool holder to my mini lathe QCTP. This one holds 3/8" shank boring bars.






Chuck


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## Twmaster

Chuck, that is a fine collection of mods to the (former) 7x10.

Nice work. Almost wish I had not got rid of the 7x I had (almost )


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## js2112au

Thanks for sharing/showing your tool post mod Chuck, it's brilliant! The design is so simple.

Buying a quick change post has been on my ever growing list of new bits for the workshop, but making one (and I've got the right sized chunks of aluminium lying around) will be much more fun and satisfying. 

You've inspired me!

James.


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## steamer

Sorry I missed all this Chuck.  Looks like a great job and a useful lathe!

Dave


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## cfellows

Thanks, Dave. Even though I have a good Logan, 11.5" lathe with lots of attachments, this mini is my goto lathe for small parts when I need accuracy. With my version of the set-tru chuck, I have less than .001" runout and the diamond tool bit is easy to sharpen and a joy to use. If I ever have to downsize my shop, the min-lathe is the one I'll take with me. Need to work on that tailstock, however. I'm completely disatisfied with the base, too small.

Chuck


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## steamer

What's the plan? New base?

Dave


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## cfellows

steamer  said:
			
		

> What's the plan? New base?
> 
> Dave



Yeah, I've been noodling around the idea of a new base. But I haven't gotten serious about it yet.


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## compressor man

> Yeah, I've been noodling around the idea of a new base. But I haven't gotten serious about it yet.



Well when you decide to make a new tail stock, make 2 and send one to me ;D I have never been happy with the tail stock on my 7x12. In fact, imo, it is the weakest part of the whole package. I agree with what so many of the guys have said here, that with some mods a mini-lathe can really be a great little machine. But my tailstock has always seemed to me to be a little iffy on repeatable centering accuracy (did that make any sense?) and the adjustment for it is a nightmare. 

Does anyone know of a good way to really spruce up the tailstock on a mini, or is there an aftermarket avaliable for sale?

Chris


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## dvbydt

Chuck and Chris,

This is the mod I did to my tailstock.












It helps to make it less wobbly, but there was a taper in the thickness of the bed and I had to use an inverted flycutter on my mill to cure it.

The first mod I did was to the cross slide handle, the capscrew was catching my knuckles so I fitted a modified csk screw. The fixed handle was too short so I made a rotating PVC one.






Ian


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## websterz

I like the new handle!! Added to my TD list. :bow:


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## V 45

Not to bring up an old post...but I'm making one now !! Question is how deep did you make the bracket cut? How much did you take off the gib> Looks like you made them so they are even with each other...is that correct ?? Thanx again... V 45




cfellows said:


> I'm getting along pretty well with my tapered gib upgrade. I'll post the last picture first so you can see what I'm trying to get to.
> 
> 
> 
> 
> 
> 
> The clamps are made from 1/2 x 3/4 inch aluminum 4 inches long. The next picture shows me milling out the side where the brass gib will fit. I've lifted one end of the clamp and propped it up with a 1/16" thick piece of aluminum to create the angle. Should be somewhere around 1 degree, although the exact angle isn't critical. Here you see the first pass removing .050".
> 
> 
> 
> 
> 
> 
> In the next picture, I've finished the clamp and am using it as a base to hold the brass gib while I mill it. By using the clamp as the base, I am ensuring that the gib taper will exactly match the clamp taper. Note that I've removed the 1/16" piece of aluminum and mounted the clamp in the vise with the base flat.
> 
> 
> 
> 
> 
> 
> Despite my initial misgivings, I have to say that so far this project has been a piece of cake.
> 
> Chuck


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## cfellows

I believe the depth of the goove on the clamp is a little under .25" on the deep end.  The gib is .25" on the thick end and probably around .14 on the thin end.  If you start with .25" thick gib material, you want to make the groove something less than .25" so the gib will contact the bottom of the way before it's pushed all the way into clamp.

Chuck


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## boxcarmj

Chuck, are you still happy with your tool post? Would you change anything on it, I'm thinking of scaleing it up some. I do like the look of it very much. Thank-you!
Mike.


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## cfellows

boxcarmj said:


> Chuck, are you still happy with your tool post? Would you change anything on it, I'm thinking of scaleing it up some. I do like the look of it very much. Thank-you!
> Mike.



Yes, I still use it most of the time.  I just made a new, general purpose holder to hold 1/2" square tool bits and other accessories. 

Nothing I would really change.  The 1" diameter post seems plenty rigid.  I think I will change the tool holder clamping screws to recessed socket head cap screws.  Less stuff sticking out and the 1/4" hex head bolts I'm currently using are crap.  The heads are so thin it's hard to get a purchase on them with a wrench.  I also just bought a bunch of wave washers so I can now set up the height adjustment nuts properly.  I'm going to post some follow-up pictures of changes and additions I've made since my last post here.

Chuck


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## Stub Mandrel

Fascinating! I have a mini lathe with many mods as well, but I think all of them are different mods to yours!

The next one is to marry up a 0.4kW 3-phase motor and inverter. I already have a layshaft fitted, but I want to upgrade to a poly-v belt at the same time.

Neil


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## cfellows

I got inspired this morning to do some more work on the minilathe.  When I did the original mods some time ago I had added a spacer on the cross slide screw to allow me to move the toolpost further out from center.  This worked to a degree, but the outward movement was still limited by length of the channel in which the cross slide nut travelled.  So, I took it all apart this morning and cut out another 1.25" which has added another inch of outward travel.






I used a 1/2" roughing end mill for the task.  Now the lathe is all back together and ready to work.

Here are the attachments I have for the lathe at this time.  There is some repetition from earlier posts.

First is the 1/2" too holder.  I need to replace the set screws with socket head cap screws...






And here is the diamond or tangential tool holder I made.






This is the compound I made which takes carbide insert and fits on my quick change tool post.






It occurred to me today that I could simply cut a shelf and dill and tap a clamping screw holder on the other side to hold a second carbide insert and I would have a reversible compound.  Think that 's going to be next on my list.






This is a small milling attachmet I had made a number of years ago for my Logan lathe  Here I've made some modifications so it fits on the cross slide of my mini lathe.  Mount this does require removing my QCTP since this mounts directly on the cross slide.











This is a 4", 3 jaw chuck I can mount on the lathe.  The steel ring with set screws around the back of the chuck let's me adjust run out to near zero.






And this is a small, 25,000 RPM AC/DC motor with a Jacops #0 chuck mounted on it.  I can use it to drill small holes and mount various dremel bits for grind, cutting, etc.  I use a variac to vary the speed on it.  






The motor is an Ameteck vacuum cleaner power head motor.  Despite the fact that it has a plastic housing, it's powerful and has a ball bearing race on the working end with a bronze sleeve bearing on the back end.  These are available on Ebay for pretty reasonable cost...

http://www.ebay.com/itm/Rainbow-Vacuum-D3C-D4C-SE-Motor-Power-Nozzle-Head-/121059461556?hash=item1c2fb4c9b4

Chuck


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## Brian Rupnow

Chuck--Perhaps its too late, but a word to the wise about the socket head clamping screws---They fill up with crap!!! Then you can't get the wrench into them without having something sharp and pointy to dig the small chips out of the sockets. Its not a real big deal, but I was just looking at your recent posts and thought I would mention it.----Brian


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## cfellows

Brian Rupnow said:


> Chuck--Perhaps its too late, but a word to the wise about the socket head clamping screws---They fill up with crap!!! Then you can't get the wrench into them without having something sharp and pointy to dig the small chips out of the sockets. Its not a real big deal, but I was just looking at your recent posts and thought I would mention it.----Brian



Good point, Brian.  However, These will be sitting horizontally, away from the lathe spindle, so I don't think there will be as much of a problem.

Thx...
Chuck


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## boxcarmj

Chuck, thanks for all the updates!
Mike.


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## Stub Mandrel

Hi Chuck,

I might copy your milling out of the slot.

A less spectacular but useful bit of extra travel for those unwilling or unable to mill can be gotten by shaping the end of the nut so it fits the curved end of the slot. About 1/2" to be found that way.

Neil


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## cfellows

I've had lathe back together and in use for a couple of weeks now.  The extra out travel on the carriage is really useful.  

Chuck


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## MCRIPPPer

do you have any pics of how you extended the lead screw for more travel? did you make an extender for the handle?


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## dkwflight

Hi
I do not have a mill yet. I am doing some half a**ed milling on my chinese drill press.

I bought the extended travel carriage kit from LMS.
Good guys  and I bought a lot of other stuff from them as well.

I did not try the tapered gib mod, no mill.
I made longer heavier carriage hold down plates for the carriage.
The shim pack was a pain to cut but now the mod is done I am very happy with it.
I made the studs and locktighted them into the carriage.
Nylon lock nuts complete the mod.
The strips are 5" x 3/4" x 3/8"
3/8 is too thick.  I had to carve a divit for the carriage traverse gear so it can mesh the rack.
In retrospect I should have made the strips the same thickness as the original.

I had the same sloppy paint job as the others. Sand paper under the rear way to clean it up. some stone work in the same area to clean a seaming variation in thickness of the way.
Now the carriage moves withe same firm pressure the whole length of the ways.
The serial numbers punched in the top of the ways needed some stoning too.

I installed the apron cover too and now have the lead screw cover kit from LMS installed.  It is pretty good except for loosing some travel at the right end.

BTW  I looked at others ideas for a carriage stop clamp. THey all have issues,
I put my lead screw in neutral and close the half nuts.  The compound feed makes any fine adjustments for facing cuts.
I added extra gib adjust screws in the compound.I think I will add a QCTpost.
This will get the tools closer to the post in the compound.
I like the heavy tool post mod, but no mill yet.

I would like a heavier tail stock assembly. Too much flex, even all locked up.

You can see the ends of the longer carriage hold down strips in the pic.


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