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View Full Version : Finally beat my new 5C collet chuck into submission



dalee100
12-26-2016, 05:03 PM
Hi,

Not sure if I got lied to about the bolt hole circle diameter, or the clearance holes for mounting the chuck to the back plate were wonky. But I turned a nice cast iron back plate that fits the spindle perfectly and the bolster to the chuck is purposely .004" undersized. I did so to have a bit of tap-tap room to indicate in perfectly.

But no matter what I tried, I was unable to get closer than .006" at best while being .010" off at 90deg. from there, (kind of an oval thing). Got pretty frustrated with it last week.

Looking at it today, I determined the bolt heads seemed to be rubbing on the counter-bores. Ok, CCC bolts do not need to be concentric with itself.....Run to town and get new and better 8mm SHCS. Try them out. Still no joy.....Drink some tea.....I finally decided that either the taper for the collets is ground out of whack or the mounting holes in the chuck are wrong.

Easiest thing to do is drill out the mounting holes if the body isn't too hard. Quick check with a file showed it to be just soft enough to drill with HSS run really slow. I had to take the holes out to 25/64", but now a couple of quick taps gave me .00015" runout at 2" from the collet face on a hardened and ground dowel pin. Good enough for me right now.

I feel soooooo much better now!:D:D

Dalee

andywander
12-26-2016, 05:17 PM
NNice!

What's a "CCC bolt"?

dalee100
12-26-2016, 07:30 PM
Hi,

CCC = Cheap, Cheerful, Chinese.