Is it my turn? Anything to do with lathes, mills and other shop tools

[TwoManyXS1Bs]

My Atlas/Craftsman lathe had an unusual runout on its 3-jaw. Rarely would have 0.001" runout, more often some variations up to 0.004". And the runouts seemed to be diameter related. Did all the usual truing-up tricks, no fix. Conventional wisdom says to never rely on the 3-jaw for accuracy, just adapt to it.

Then, about 35 years ago, had an epiphany. It must be the scroll.

Example pic.


Chucked-up the scroll in the 4-jaw, centered on the scroll's ID, and took meticulous measurements of the scroll's threads. My scroll's threads have a pitch of 0.200" per turn.

Very long story short, sure 'nuff, my scrolls weren't concentric with the scroll's ID. Recentered the scroll in the 4-jaw, centered on the inner (bearing) surface of the scroll threads. Found the ID to have about 0.003" runout. Bored it out a bit, fitted a sleeve, bored that to a 0.001" fit on the check body.

Scroll now concentric with the chuck, regrind the jaws.

Now my 3-jaw runs less than 0.001" runout.

Quite handy...

 

[Beags64]

"Stole" this off Fleabay a couple years back ($45 IIRC, nobody else bid). 8" Rhom, the twist being each jaw is adjustable like a 4-jaw but then the big screws in the body operate the scroll like a 3-jaw. Haven't put a back plate on it to use it on anything but sure sounds like it should work sweet.

 

[Beags64]

Ah, but there are many who can turn that thread for you , and more than a couple happy to do it for small compense 'cuz they like to do machine projects.

+1 on what Gary says. With a few measurements it wouldn't take much to turn a sleeve with the proper thread and register I.D. that could be welded onto a round plate, turned, faced and drilled to fit the chuck of your choosing. I'm game to help.

 

[Downeaster]

Ah, but there are many who can turn that thread for you , and more than a couple happy to do it for small compense 'cuz they like to do machine projects.

If anyone is truly up for this, please PM me. I'm thinking send whomever my old mounting adapter and my new chuck and at the very least pay for materials to make a new mount. Wouldn't be anytime soon, more of an over-winter project.

 

[Downeaster]

Beags64, a chuck like that would solve a number of problems for me, for sure. I'll have to keep an eye out for one.

Where are you in Michigan? I'm headed for Mount Pleasant the second week of September, be around T/W/T of that week.

 

[Beags64]

I'm in Durand, 'bout 1/2 way between Lansing and Flint (mmm...Flint water). Just sent you a PM, that could work out, if we got our poop in a group I could prolly have something made for you by the time you were in the area.

 

[Ratranger]

I got me a rotary table finally. Now the loss of access to the waterjet at my last job is less limiting. It is used, and could probably stand a good cleaning and lube.

 

[gggGary]

Nice size AND the 90 degree mount.
I went through the 12" I got and it was well worth doing.

 

[Ratranger]

It's an 8". I wouldn't have minded larger, but budget and availability meant picking up this one.

 

[gggGary]

IMHO the 8" is ideal, the 12" is a HEAVY SOB
I'd trade you in a heart beat.

 

[Ratranger]

Yeah, even the 8" is pretty heavy. Makes the 6" kurt vise seem light on comparison.

 

[Downeaster]

Well, seeing as building/fixing another bike is not on the menu for the foreseeable future...

I went and grabbed another lathe off Craigslist. It was a freebie and I snagged it mostly for the 4-jaw chuck that's on it. Disassembled it, loaded it on my trailer and lugged it home yesterday.

Finished tearing it apart today and now I'm in a quandary. I don't see anything major missing and what's there seems to be complete and in reasonably decent shape. I'm about 90% sure I could clean it up, lube and adjust it and make chips with it. I surely don't NEED a third lathe, but I hate to scrap a usable machine. It doesn't have change gears so threading wouldn't be an option but if it runs and is reasonably accurate, it'd make a nice starter lathe for someone.

Thinking it'd make a nice Winter project and I could have a little fun then let it go cheap to someone and maybe put a couple of bucks in the toy fund.

Or, it could just take up space in my garage for several months and then wind up in the recycling dumpster anyway...

EDIT: I've gone over the bed, legs, pan, headstock and apron with everything but a magnifying glass and can't find a single marking anywhere to indicate who made it.

 

[Jim]

EDIT: I've gone over the bed, legs, pan, headstock and apron with everything but a magnifying glass and can't find a single marking anywhere to indicate who made it.

Put a pic up here.

 

[Downeaster]

I've got it tore down plumb to parade rest at the moment. The pic in the post above is the only full shot.

If you think a shot of something in particular might help, let me know and i"ll post it.

 

[Jim]

The pic in the post above is the only full shot.

I don't see a pic DE.

 

[Downeaster]

Ah...I linked it from another site. Lemme fix dat, BRB

 

[Downeaster]

Better?

 

[Jim]

Better?

Yeah.... not good enough to tell the brand though....

 

[azman857]

I'm no expert on this kind of thing but it looks to be from days of when belts powered it.

 

[gggGary]

I know little too. But ancient southbend wouldn't surprise me.
https://www.practicalmachinist.com/vb/south-bend-lathes/south-bend-9-junior-lathe-347473/