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Truing A 5C Collet Chuck - Its All Dave's Fault
- Thread starter Amigo
- Start date
- Joined
- Sep 22, 2010
- Messages
- 898
Personally I think that the stock should be held in a 4-jaw and dialed in, that way the 3-jaw inaccuracies don't telescope into the collet chuck.
Hopefully the Bison I just ordered will be tickety boo without any tweaking.
Walter
Hopefully the Bison I just ordered will be tickety boo without any tweaking.
Walter
A setup as Jack posted looks to be the ticket to true up the back of the 5C chuck. The stock held in the 3 jaw is turned to diameter I would think 3/4" would be a good number. That shaft would be concentric to the centerline of the lathe spindle. Then the 5C's 3/4" collet closed on the turned stock to grip on and a bull nose center supporting it from behind. I think the only thing that would really make this setup even better would be the use of a tool post grinder to make the mandrel and to clean up the back of the chuck.
- Joined
- Sep 22, 2010
- Messages
- 898
Agreed, as long as the stock is put into the 3-jaw chuck and turned to diameter, then the collet chuck attached. If this is done the other way around, place stock in collet chuck, then grip in 3 jaw chuck, now face the collet chuck you will have the inaccuracies of the 3 jaw chuck compounding and not get an accurate face.
Walter
- Joined
- Jan 20, 2013
- Messages
- 275
I have a Chinese 5C Collet chuck that looks like the one in the pictures above. I carefully made an adapter plate to mount it to the head stock of my lathe. Very close fit. I checked the runout and ACK it was like .005 !! I was not a happy camper! I was considering sending it back!
Then I had an epiphany.
I mounted the chuck and marked the adapter and chuck and the lathe head so that I always return it to the same place rotationally on the lathe head.
I have a ½ square shank tool adaptor for my Dremel like this:
http://www.ebay.com/itm/Dremel-tool...913?pt=LH_DefaultDomain_0&hash=item19d5f5cfc1
I mounted a grinding wheel in the Dremel in the tool post and set the compound to the same angle as the head of a 5C collet.
Then, slowly but surely, with the Dremel and the lathe running, I reground the inside of the mouth of the chuck with the compound slide.
It really didn’t remove much material and I don’t remember it taking that long to do.
Obviously, this means the collet ends up some tiny amount deeper in the chuck but not enough to be functionally or even visibly noticeable.
But guess what! The run out was down to next to nothing!
Of course, I had to clean the lathe and chuck etc etc after using the grinder on it.
I think this is a good way, if not the only way to insure concentricity. I hope I have made myself clear.
Dave (It's not my fault, that's a different Dave)
Then I had an epiphany.
I mounted the chuck and marked the adapter and chuck and the lathe head so that I always return it to the same place rotationally on the lathe head.
I have a ½ square shank tool adaptor for my Dremel like this:
http://www.ebay.com/itm/Dremel-tool...913?pt=LH_DefaultDomain_0&hash=item19d5f5cfc1
I mounted a grinding wheel in the Dremel in the tool post and set the compound to the same angle as the head of a 5C collet.
Then, slowly but surely, with the Dremel and the lathe running, I reground the inside of the mouth of the chuck with the compound slide.
It really didn’t remove much material and I don’t remember it taking that long to do.
Obviously, this means the collet ends up some tiny amount deeper in the chuck but not enough to be functionally or even visibly noticeable.
But guess what! The run out was down to next to nothing!
Of course, I had to clean the lathe and chuck etc etc after using the grinder on it.
I think this is a good way, if not the only way to insure concentricity. I hope I have made myself clear.
Dave (It's not my fault, that's a different Dave)