Spec Grade
Member
I'm having problems drilling straight holes in my pen blanks. Here's my setup: I have a bench mounted heavy duty drill press. (3/4 hp, all cast iron, etc.) It has been leveled, shimmed, checked 3 ways from Sunday, etc.
It's bolted down to a 4" thick rock maple bench top, with 3/4" carriage bolts.
The drill plate is dead level. I'm using a machinist's drill press vise, which is machined perfectly flat. I also use a Speed Square to align the blanks in the vise, to make sure they are perfectly plumb. I have also changed the drive belts, had the sheaves machined & balanced, etc.
I use a laser calibrated chop saw to cut my blanks, so I know that's square & plumb as well.
I have checked all my drill bits, none are bent or warped. I have used brad point bits, spade bits, you name it, and yet my blanks have significant drift in them. I drill very slowly at low speeds (~350-500 RPM's). I relieve the drill hole at 1/8" intervals.
(Meaning: I drill like Grandpa drives.)
I have checked my drill press for wobble, bearing warp, etc., nothing there. But, whenever I drill a pen blank, it invariably comes out at a different point than when it entered the blank. I mark both ends with an "X" to see where it comes out at.
I have even went so far as to have a professional come out & adjust my table saw for perfect squareness.
(That wasn't cheap by any means.)
Yet, the problem persists.
Does anyone have some insight as to why I still have drift when drilling a 2.5" wood blank for making pens?
It's baffling the hell out of me.
It's bolted down to a 4" thick rock maple bench top, with 3/4" carriage bolts.
The drill plate is dead level. I'm using a machinist's drill press vise, which is machined perfectly flat. I also use a Speed Square to align the blanks in the vise, to make sure they are perfectly plumb. I have also changed the drive belts, had the sheaves machined & balanced, etc.
I use a laser calibrated chop saw to cut my blanks, so I know that's square & plumb as well.
I have checked all my drill bits, none are bent or warped. I have used brad point bits, spade bits, you name it, and yet my blanks have significant drift in them. I drill very slowly at low speeds (~350-500 RPM's). I relieve the drill hole at 1/8" intervals.
(Meaning: I drill like Grandpa drives.)
I have checked my drill press for wobble, bearing warp, etc., nothing there. But, whenever I drill a pen blank, it invariably comes out at a different point than when it entered the blank. I mark both ends with an "X" to see where it comes out at.
I have even went so far as to have a professional come out & adjust my table saw for perfect squareness.
(That wasn't cheap by any means.)
Yet, the problem persists.
Does anyone have some insight as to why I still have drift when drilling a 2.5" wood blank for making pens?
It's baffling the hell out of me.