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2 flute vs 3 flute spiral upcut

19K views 6 replies 5 participants last post by  Flipsaw  
#1 ·
Wanted to get some opinions. Looking at Whiteside Carbide 1/2" x 2" bit and there is only a $3 difference in the price.
Thanks in advance.
 
#2 ·
What material are you cutting, are you cutting by hand or CNC, are you looking for a finishing cut or roughing out, what's the bit speed, etc.?

I would use the 3 flute for a finishing cut and the 2 flute for general purpose and roughing out. But then, I also use the 2 flute for my finishing cuts on the CNC most of the time.

David
 
#5 ·
You can get single flute spirals too. Fewer flutes cut faster but leave a poorer finish. Any bit that small a diameter can be run full speed (up to about 1.5”) but that not give you the best results. Fewer teeth on a table saw blade work the same way finish wise.
 
#6 ·
The 3 flute bit will remove around 1.5 times as much material as the 2 flute bit so the feed rates should be faster or the spindle speeds should be slower to keep the bit from building up heat that could cause the cutting edge to dull faster. Best to check the manufacturer's specs and go from there to git the best performance and life from the bit.