Forstner bits

[gedereco]

could anyone tell me the right speed to run forstner bits on a pillar drill. I only have a bench mounted 5 speed pillar drill but i'm not sure whats best speed to run at . any help would be much appreciated

 

[Steve Maskery]

Gedero
It depends on what you are cutting and what diameter the bits are. AFAIK there is no difference in cutting speed, diameter for diameter, between a Forstner and, say, a twin-lip-and-spur, but I'm open to correction there.

If you are using a 1/4" forstner, turn the speed up, and if you are cutting 2" holes get is as low as it can go, especially if you have only 5 gears.

If the whole machine vibrates around the floor (or off the bench) you have the speed set too high!

Steve

 

[lugo35]

hi generaly forstener bits are run slower. there is alot of metal touching the wood and you will get alot of heat build up if running to fast.

 

[beejay]

http://www.ibiblio.org/twa/info/drillSpeedChart.pdf

The above link will give you a drill press speed chart for all sorts of bits.
regards,beejay

 

[Steve Maskery]

Crikey, if I read that correctly they actually recommend a Forstner to run faster (in softwood - small sizes) than a twin-lip-and-spur. I must try that.
Thanks for the link.

Cheers
Steve

 

[gedereco]

many thanks for all your help that chart is a good reference point. Thanks