Chuck Grinding

[Mork]

I thought I'd share how I ground my 3 jaw chuck. It was worn pretty bad but now it only has .003 run out. I made a ring to load the chuck and ground the inside of the jaws.



Then I mounted a dremal to the tool holder and ground very slowly.... for like 2-hours!
I'm sure a more solid arrangement would have made quick work of the job but you work with what you have. It worked great... just slow.

 

[brino]

Hi Mork,

Welcome to the site!

Sounds like you had some success, congratulations!

Can you post a larger picture? The first one came thru as a small thumb-nail only. I cannot see much detail.

Thanks,
-brino

 

[Kernbigo]

where you made the ring to load the 3 jaws all i do is use 3 gage blocks at he angles(they may be 45 dreg.) not sure. Then i use my dremel tool with a diamond wheel takes about 10 minutes. I also made my chuck into a adjustable (like a buck) can indicate it down to a couple tenths.

 

[Mork]

Ahh... yeah, 3 blocks would work! I turned a disk... a bit more work for sure but accomplished the same. My mounting set up was not very solid. I'm sure I could have taken much more at a time if it was. A diamond stone would definitely help also.

Here's some larger pictures.

 

[brino]

Thanks Mork!
Now I understand how that worked to load the jaws.

-brino

 

[wa5cab]

Right. If you make a ring to go around the outside of the jaws and tighten them out into it, and then grind the inside of the jaws, you will undoubtedly end up worse off that you were to begin with. This seems to be a common mistake. When you do this, the jaws are tightened in the direction opposite that in which they are tightened on a small diameter workpiece. The jaws cock slightly due to clearances in the slots that the jaws run in. And you end up with a condition that I will call anti-bell mouth.

 

[Ed of all trades]

Thanks for the info. I keep learning of things that I need to learn. Ed