can i adjust the jaws on my taig lathe headstock?

snipershot

snipershot

Go ahead.....run for it.
Silver Member
I haven't indicated yet, but I will when I get home from work, but I'm thinking my chuck on my headstock might not be running true because when I put a shaft on s sneaky I'm making, the shaft is fitting quite a bit off-center. Id say its at least 15-20 thousandths off. I've put pins in two butts two different ways, and its still off. Ill post some pics later to show how I did it. So, if I'm doing it right, what could be the reason for the shaft not fitting right? I used the same shaft on two other 3/8 10 cues and it fit like a glove.

Joe
 
Those 3-jaw alum chuck are easily .003" off .
You can't adjust them. You can shim though.
 
snipershot said:
I haven't indicated yet, but I will when I get home from work, but I'm thinking my chuck on my headstock might not be running true because when I put a shaft on s sneaky I'm making, the shaft is fitting quite a bit off-center. Id say its at least 15-20 thousandths off. I've put pins in two butts two different ways, and its still off. Ill post some pics later to show how I did it. So, if I'm doing it right, what could be the reason for the shaft not fitting right? I used the same shaft on two other 3/8 10 cues and it fit like a glove.

Joe
Click to expand...

My cue done yet?
 
This is my method to true up the jaws. I make a piece of purple heart right 1-3/8 it just goes through, I tighten up on the wood just behind the soft jaws on the hardened steel behind them. The rear jaws hold it steady. I use a carbide helical boring bar to just shave off a couple thousands. I can get my jaws to run under 1/4 of a thousand run out, or even better.

Give it a try you will be surprised, if you have a piece of delrin that size it works too.
 
Trent said:
sounds like your pin isnt on center.
Click to expand...

I thought that was the problem too on the first cue, so I put the pin in first on the second cue and chucked it up in my headstock using a 3/8 10 drive pin. Then I cut the joint down. I thought that would ensure the pin would be dead center, but the shaft still doesn't fit right. Its playable, but as I learn to do this stuff, I wanna be as perfect as possible.

Joe
 
doesnt matter, if your lathe is running out you will cut ovals lol

they make steel jaws for those chucks on ebay, i was going to buy them when i had my deluxe but went with a metal lathe instead. i spent as much time boring jaws and trying to get runout down than anything else.
 
Trent said:
doesnt matter, if your lathe is running out you will cut ovals lol

they make steel jaws for those chucks on ebay, i was going to buy them when i had my deluxe but went with a metal lathe instead. i spent as much time boring jaws and trying to get runout down than anything else.
Click to expand...

Damn. I guess I'll look on ebay when I get home then.

Joe
 
somewhere is a post where I showed how I made the chucks adjustable.. Although I did mine on the 4jaw chucks, it can still be done to the 3 jaw chucks. You can use 3 or 4
adjusting points. I prefer 4 to 3 adjusting points.I said in the article to use plastic, but I changed mine to use brass pads and works great.
Neil
 
bnall said:
Hell where am I on the list?
Click to expand...

Well, since you didnt agree to my contract terms for ordering a cue, (most notably the 125% up-front non-refundable deposit and naming me in your will to inherit your MC cue that I love if you should pass) you have been moved significantly farther down the list. We here at the snipershot cue company appreciate your business, lol.

Joe
 
Trent said:
doesnt matter, if your lathe is running out you will cut ovals lol

they make steel jaws for those chucks on ebay, i was going to buy them when i had my deluxe but went with a metal lathe instead. i spent as much time boring jaws and trying to get runout down than anything else.
Click to expand...

Well I found those steel chucks, but after I got home tonight, I indicated the chuck and it was only about .003 out. I put a pin in the drive pin and indicated the pin, and it was about .035 out, so Its safe to say that method of cutting the joint failed miserably, lol.

Joe
 
snipershot said:
Well I found those steel chucks, but after I got home tonight, I indicated the chuck and it was only about .003 out. I put a pin in the drive pin and indicated the pin, and it was about .035 out, so Its safe to say that method of cutting the joint failed miserably, lol.

Joe
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well at least you found the problem but i try to keep my run out under a thou, half a thou if possible.

its still a good upgrade to think about, jujst from now on keep your dial indicator handy and indicate everything and use masking tpe on the jaw sticky side to the metal when your shimming them that way the shim can come off incasew your piece moves in the chuck. .003 seems like a bit much, its that much 2 inches from the chuck its going to ge tons 29" from the chuck.

good luck:thumbup:
 
Snipershot,

There was a fairly long thread here about a year or more ago about how to true up your headstock by boring the jaws ever so little. IIRC the problem was that with a scroll chuck, the truing is only going to be repeatable at the diameter that you originally bored the jaws at. So I like to bore mine at around .625" - 650" as that is right in between the final diameters of tips and joints. My assumption is that the inaccuracy in the chuck is linear, meaning that it gets greater as you move farther away from the original bore diameter.

Tony@Russell Cues- is that your experience or does your runout hold true through the entire range on your chuck?

Neil (Conetip) - I remember your post, but I didn't quite understand it at the time. I'll have to go search and read it again.

Finally, before you bore anything, get yourself a known straight rod, chuck it up and measure the runout along the length of the rod. If it is off, you're going to have to try to determine if it is because the jaws are out or the headstock is not true to the ways. This is tricky to differentiate. But if the headstock is not true, then boring will simply bore a cone in your jaws and not a cylinder.

Sorry for the rambling post.

My 2 cents (based on my experience),

Gary
 
GEBrown said:
Snipershot,

There was a fairly long thread here about a year or more ago about how to true up your headstock by boring the jaws ever so little. IIRC the problem was that with a scroll chuck, the truing is only going to be repeatable at the diameter that you originally bored the jaws at. So I like to bore mine at around .625" - 650" as that is right in between the final diameters of tips and joints. My assumption is that the inaccuracy in the chuck is linear, meaning that it gets greater as you move farther away from the original bore diameter.

Tony@Russell Cues- is that your experience or does your runout hold true through the entire range on your chuck?

Neil (Conetip) - I remember your post, but I didn't quite understand it at the time. I'll have to go search and read it again.

Finally, before you bore anything, get yourself a known straight rod, chuck it up and measure the runout along the length of the rod. If it is off, you're going to have to try to determine if it is because the jaws are out or the headstock is not true to the ways. This is tricky to differentiate. But if the headstock is not true, then boring will simply bore a cone in your jaws and not a cylinder.

Sorry for the rambling post.

My 2 cents (based on my experience),

Gary
Click to expand...

When I use my method, the runout is the same in pretty much all positions. The key is, I believe, I'm holding the jaws steady as possible by chucking how I mentioned earlier, you get a very true bore. IMO
 
Russell Cues said:
When I use my method, the runout is the same in pretty much all positions. The key is, I believe, I'm holding the jaws steady as possible by chucking how I mentioned earlier, you get a very true bore. IMO
Click to expand...

I used the same method as Tony did on my chucks. With all my chucks, they only ran true at very close to the diameter they were bored to.
All other diameters, and they were up to .008 inch runout.
So I have 1 chuck bored to 30 mm and I only hold 30 mm diameter sleeves etc in that chuck.
All the others I modified to make adjustable. I am not sure where exactly the errors are from.
My own suspicion is that the scroll is not concentric to the bore of the chuck, but I have no way to check it either way.
 
Well, first of all let me say thanks to all of you for your advice! It makes sense that if its 3 thou off at the chuck that it would be a mile off at the other end when I'm spinning the cue, so ill go ahead and follow the directions about boring the jaws out and give it a try. If that doesn't do it, I'm gonna go crazy, lol.

Joe
 
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