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tjskcnc
07-15-2009, 08:18 AM
New to CNC machining but an 'old timer' to woodworking. The whole 2 - 3 - 4 flute thing has me confused. I am open to any suggestions.
I work with all woods, from pine to maple to walnut, and cut 3D into burl, from stuff as soft as manzanita and as hard as maple and walnut. I need flat end bits for "pocket" type cuts - I've been using regular single flute carbide router bits for 1/4 inch cuts and 1/8 inch single flute HSS spiral bits for smaller cuts - the 1/8 bits are surplus from the local saw/bit shop - hey, I'm a newbie - I don't know any better :) .
I've been using 1/4 inch 4 flute ball end carbide bits and 1/8 inch 2 flute ball end carbide bits for 3D cutting.
Finished pieces come out fine, but the 4 flute bits tend to 'burn up' in harder woods.
I need to shorten my learning curve (shorter learning curve saves money!!!)
If I need different bits for different woods, that's fine (not really - that means more money, but you do what ya gotta do.) Interested in anyone's experience as to what works best in different woods.
Thanks.

ger21
07-15-2009, 09:16 AM
Those 4 flute bits are probably for metalworking. Typically, the most flutes you'll find on woodworking tooling are 3, and those tools are designed for extremely high feed rates, up to 2000 ipm for 1/2" tools. With small tools, 2 flutes are probably the best bet. Good 3 flute woodworking bits may be an option, if you want to run at very high feedrates. (~300+ ipm) Check out www.vortextool.com for good quality woodworking bits.

Big-tex
12-01-2009, 11:46 AM
Number of flutes has great influence on feeds and spindle speeds.
I can refer for self study my good ol favotite onsrud catalog with chip load charts and formulas. You do not have to use that brand but I think it will give you general idea.

https://www.onsrud.com/OC/pdf/OC-08CatalogR.pdf

ftec
01-08-2010, 05:08 AM
Those 4 flute bits are probably for metalworking. Typically, the most flutes you'll find on woodworking tooling are 3, and those tools are designed for extremely high feed rates, up to 2000 ipm for 1/2" tools. With small tools, 2 flutes are probably the best bet. Good 3 flute woodworking bits may be an option, if you want to run at very high feedrates. (~300+ ipm) Check out www.vortextool.com for good quality woodworking bits.

Can't you just halve the spindle speed if you have a 4 flute bit instead of 2 flutes? I've found it really difficult to find suitable ball nose bits for woodworking so I ended up ordering a lot of 4 flute tools. Haven't got them yet, will see how they work.

And thanks for the vortextool link, any other brands for woodworking bits?

ger21
01-08-2010, 07:50 AM
Can't you just halve the spindle speed if you have a 4 flute bit instead of 2 flutes?

Depends how fast you're spinning. I run 1/4" 2 flute bits at 10,000-12000 rpm. My router can't spin any slower.

As for small ballnose bits, I just got some 2 flute 1/16" (1.6mm) and 1/8" on Ebay.

I'm also looking for some tapered ballnose, but have only found those in 3 or 4 flutes. When using those small bits with very small stepovers for carving, it shouldn't really be a problem.

There's a bunch of suppliers in this thread.
http://www.cnczone.com/forums/showthread.php?t=96275

ftec
01-08-2010, 03:13 PM
Thanks Gerry!

mcphill
01-08-2010, 04:01 PM
Precise-Bits has a decent selection as well, and are very helpful over the phone for assistance. Here is one page, but look around the site a bit. Not the easiest to navigate, but good info in there:

http://www.precisebits.com/gateways/EndMillsHome.htm