Chipbreaker / Finisher Bit Size

[woodshopcnc]

We have a 48 x 96 PRS with the 2.2 hp spindle, ER 25 collets. Typically I use a 1/2" 2 flute chipbreaker / finisher for most hardwoods using multiple passes with a final clean up pass.

Will the 2.2 handle a larger diameter bit, say a 5/8" or a 3/4". I know they make collets in the larger sizes but didn't know if it's a good idea or not.

Stephen

[rhfurniture]

How deep are you cutting?
I use 16mm (5/8) x 170 cutters 2flute to cut 130mm deep (Bubinga - it JUST about works...), 14mm insert straight incrementing in from outside up to 60mm deep (works a treat) but up to 20mm I use 10mm dia cutters. Horses for courses.

R.

[woodshopcnc]

R,

Usually it's just 3/4" or 1" material, typically free form geometric designs. I usually go about 1/4" per pass with about .03" offset from the part then a full depth final pass cleaning up the .03". Mostly in hardwoods, oak, cherry, walnut.

Your cutting 130mm (5 1/8") deep? How many passes? Are you on a 2.2 or larger spindle?

S.

[beacon14]

The 2.2 hp spindle should have no problem with a 5/8" or 3/4" bit, you probably want to keep the RPMs on the low side. We use a 2 1/2" diameter spoilboard surfacer at 12K RPM to cut up to 1/8" deep in hardwoods.

[tomwillis]

David - what speed would you normally run that 2 1/2" surfacer bit - that's cutting 1/8 deep?
Tom

[tomwillis]

David - I meant what feed rate?
Tom

[beacon14]

4 ips for hardwoods up to 1/8" deep, maybe 3 ips for a delicate or critical surface.

8 ips for surfacing the spoilboard at .014" deep