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View Full Version : Forstner Bit in a Spindle?



johnm
08-02-2006, 02:48 AM
Hey All -

What do you think? We would be drilling a host of 1 5/8" Dia 1" deep holes in Hard Maple. I think this would be faster than doing an area clear using a 1/2" End Mill, even factoring tool changes.

I know I'd have to dial the RPM way down...

Pros & Cons??

John

elcruisr
08-02-2006, 09:10 AM
Very scary in my book. You'll have lost alot of torque when dialed down to those speeds and may well stall the spindle. I figure if it was a good idea then you would see it used on alot of the big machines, all the ones I've seen do area clears. If you get brave and try it though it would be interesting to hear the results!

richards
08-02-2006, 09:43 AM
John,

Don't do it! On my drill press I run large forstner bits at 200 rpm and even then, I peck drill every hole. Even if your spindle could produce enough torque to drill the holes, you would have to stand guard with a bucket of water to put out the friction caused fires.

mikejohn
08-02-2006, 11:30 AM
Cutting the hole with a 1/2" bit should be very fast
I am always suprised at the speed
it takes seconds
...........Mike

mikek
08-09-2006, 08:18 AM
John, all CONS here. I would bet the fire starts about halfway through the first hole and the bit will be trash at that point. As Mike R. said, very slow with that large bit in a drill press ONLY! It may still burn hard maple unless it is very sharp. Don't chuck up anything but router bits or end mills in a router or spindle.