Quality of Grizzly vs Shars Chucks

[G-ManBart]

Pick up the phone and call CME. If you’re lucky enough to get the employee (can’t recall his name offhand) he is super helpful. He steered me away from the CME backplate when I bought a 6” adjustable structure 3 jaw chuck because it was too thin.

Gary is the guy who usually answers the phone there and he is super helpful. If it's been a while since you talked to him about that backplate they now have them that are much thicker specifically for adjustable structure chucks. Honestly, I wish they were a bit thinner but that's an easy (if messy) fix.

 

[CJ5Dave]

Is the boss recess supposed to be clearance or interference fit?

 

[CJ5Dave]

I got the recess done on the threaded collar, then bolted it on with 3 - 1/2 inch flat head bolts. Had to order these and the countersink from McMaster Carr. Now to turn a shoulder for the chuck itself to set into. This insert does not like cast iron at all. Turned it to a new cutting surface and it was dull again in no time. I need to take this down about an inch.

 

[WobblyHand]

I got the recess done on the threaded collar, then bolted it on with 3 - 1/2 inch flat head bolts. Had to order these and the countersink from McMaster Carr. Now to turn a shoulder for the chuck itself to set into. This insert does not like cast iron at all. Turned it to a new cutting surface and it was dull again in no time. I need to take this down about an inch. View attachment 501758View attachment 501759

What RPM? What diameter? Maybe the RPM you are turning is too fast? What kind of inserts?

 

[G-ManBart]

Something that diameter has to be turned slower than you may think, even with carbide, because the SFM is going to be fairly high. In cases where I've had to take that much off a face plate I don't turn it off, I make a trepanning tool and part it off as one big chunk...it's a lot less of a mess and once you're all set up only takes a couple of minutes to complete. It's really nothing more than a parting blade with curved sides so you can plunge from the front. Use a fairly slow speed, get the tool really sharp and it'll slice through easily.

 

[CJ5Dave]

Yes I slowed it down from 700 to 38 rpm. The plate is 10 in. The insert (TCMT with chip breaker) is written on the box in photo. Speed fixed it.

 

[GeneT45]

Yes I slowed it down from 700 to 38 rpm. The plate is 10 in. The insert (TCMT with chip breaker) is written on the box in photo. Speed fixed it.

Are you getting a good finish at that speed? I'd have expected ~250rpm.

GsT

 

[CJ5Dave]

Good enough. Not the best.