Tailstock mounted pencil grinder for chuck jaw truing?

[expressline99]

Is there any reason the tailstock on a lathe couldn't have the ram removed and replaced with a pencil grinder? To me it seems like this would make really good alignment for chuck jaw repair. The movement of the grinder would have to be controlled by the handle in the tailstock of course. The grinder would have to be a tiny pneumatic and It would take some doing to make it work in the place of the tailstock ram. I would think with the lock down of the tailstock it would be stable assuming you could get the grinder mounted properly. Could be a cheap way of making a "tailstock" grinder.

(yes I know there shouldn't be any grinding/grit near a lathe.)

So am I off my rocker again?

Paul

 

[richl]

The jaws and the tailstock would have to be lined up to where you are grinding, with the cross slide you can move the grinder right or left in relation to the ways to hit the jaws of the chuck. With the grinder in the tailstock there is no side to side movement... at least non that I can see...
There might be other uses for that configuration, not sure grinding the jaws on your chuck would be one.

Hth
Rich

 

[Bob Korves]

A standard hand held air die grinder with a 1/4" collet mounted with an adapter in the tool post would be a much betters solution, Paul. You cannot do accurate work with a skinny shank grinding wheel (flexes too much, cuts too little, and the springiness makes it cut all the way around the work, not just on the high spots) and you could only do center line work using the tailstock unless you offset the tailstock, which is also a PITA getting it back on center again after grinding if lacking the right setup. Mounting to the tool post allows easily swiveling the die grinder for the angle you need, even if it is zero degrees, and adjusting up and down to be truly on center line. It is also fairly easy (but slow) to use a sine bar to set an accurate angle. Even grinding something like a Morse taper requires several orders of magnitude more accuracy than you can get out of the degree markings on the cross slide.

 

[expressline99]

The reason I'm even considering any of this is for a 3 jaw chuck that I have mounted/bought a while back. But the jaws are completely flat.


Not sure what to do with them?

Paul

 

[Bob Korves]

Use them on triangular or hex stock?

You could grind them to a radius, but it will not very useful for smaller work unless you also narrow the jaws toward the center so they interlock like how most chucks are made. I still recommend more rigid tooling than a pencil grinder...

 

[expressline99]

Use them on triangular or hex stock?

You could grind them to a radius, but it will not very useful for smaller work unless you also narrow the jaws toward the center so they interlock like how most chucks are made. I still recommend more rigid tooling than a pencil grinder...

Oh yes, sorry I meant to say I agree with both of you. The flex would be awful and no easy adjustment while grinding.
Want a surface grinder project? It wouldn't fix alignment but seems like it would be difficult otherwise to get that much material off of them.

Paul

 

[BGHansen]

So I'm guessing you'd advance the cut or grind by tightening the chuck jaws? Make a pass with the lathe running, back the tool out, shut off the lathe, turn the chuck key a little and repeat? As Bob mentioned above, you'll be limited in diameter unless you bevel the jaws. Might be easier to just mount a die grinder on the close slide as Rich mentioned above. Nice L-W chuck by the way, have one of their dividing heads. They made great quality stuff.

Bruce

 

[JimDawson]

This is the way I do it. In this case grinding the 5C taper in a collet chuck. Harbor Freight air die grinder.

 

[richl]

Not sure this is even a good idea... but... would making a soft jaw to attach to the existing jaws a worth while idea here? From the picture the existing jaws seem a bit short already, and grinding a bevel on them will only decrease that more... I don't see stuff like this mentioned anywhere so I am just tossing out ideas for public consumption...

Nice little diy project. Ever notice that small projects soon become big projects by the time you factor in all the additional steps and tools required...

 

[expressline99]

So I'm guessing you'd advance the cut or grind by tightening the chuck jaws? Make a pass with the lathe running, back the tool out, shut off the lathe, turn the chuck key a little and repeat? As Bob mentioned above, you'll be limited in diameter unless you bevel the jaws. Might be easier to just mount a die grinder on the close slide as Rich mentioned above. Nice L-W chuck by the way, have one of their dividing heads. They made great quality stuff.

Bruce

That's probably what I'll have to do. I have an HF die grinder somewhere I've never used that I got with a bunch of other stuff. The Jaws do need a bevel for sure It doesn't tighten down far enough. Not sure how to do that though?

The chuck was basically new. Whoever had the chuck originally bored it out all the way through to a dimension too large to thread for my lathe. I took it completely apart and the grease was mostly solidified it had sat for so long. The movement on it is really smooth. I didn't even notice the jaws were flat until I started making the plate for it.
A dividing head is on my list for sure. So L-W was a good brand? Seems like a quality tool.

Paul