Mortises and Other Holes with a Drill Press
2009.10.02
Today I went to my friend Brian’s place to use his drill press. Which is what I should have done in the first place a couple or three months ago… but anyway. I took a small cardboard box full of drill bits of various sizes and types, many of which I ordered specifically for this project.
Big Holes
Most of what I ordered were sawtooth forstner bits, such as this 2–1/8″ bit that I started with. The chip-clearing works well until you get down pretty deep in the hole. I had to stop the drill press periodically and pull the bit back out to clear the shavings.
Bad Vibes
This particular hole had to go all the way through the leg; this is where the wood vise screw will pass through. This is a very large hole to drill so deep and the drill press, while pretty beefy, did not like it. Oh the motor never stalled or anything, but the vibrations (probably from exaggerated runout with such a wide bit, not to mention the weight spinning around) shook the entire drill press and sometimes made the most horrendous squealing noises as the sides of the bit rubbed against the inside of the hole.
My progress was hampered by the drill chuck shaking loose from the arbor every so often. Each time I had to unclamp my workpiece and move it out of the way, take the bit out of the chuck, get a scrap of wood and a hammer, and bang the chuck back onto the morse taper. Then get everything set back up again and continue drilling.
Monster Forstner Bit
This is probably one of the largest drill bits you’ve ever seen, a 3–1/2″ sawtooth forstner bit. (The largest of these that Lee Valley sells is 4″.) As I progressed through different drill bits, I was careful to change the belts to run the drill press at the appropriate speeds. I used the slowest setting possible for this bit, 215 RPM. It was still scary, but fortunately I only needed to go down a quarter of an inch.
Adjustable Wing Cutter
Then there is this even more frightening device: a large circle cutting bit, sometimes called a wing cutter, fly cutter, etc. You can carefully adjust the radius with the long screw, then lock everything down with an allen wrench. I needed this to cut 5″ diameter circles in the white oak vise chops. Again, fortunately only to 1/4″ depth. The circle cutter came with no directions, so I assumed the cutting bit was oriented correctly. Progress was very slow and very noisy (not to mention nerve-wracking), and the wood was burning as it went. I finally got the first hole down to the depth I needed. Brian wondered if the cutter should be turned the other way, so I rotated it 180 degrees before trying the second hole. Wow what a difference! The progress was quick, there was very little burning, and it made nice shavings instead of burnt sawdust.
Mortise Holes with the Drill Press
From there I moved to somewhat smaller forstner bits, primarily to drill out mortises. Even with the 6″ travel of Brian’s drill press, I could not drill the through mortises all the way through, because the bit itself was not that long (so the chuck would hit the top of the wood if I tried to go deeper). But even most of the way through should be a big help.
Ducks in a Hole
Finally, I drilled a series of 3/8″ holes in what will become the parallel guides for the vises.
Long Day
I had arrived at Brian’s house around noon, and figured it would take me a couple hours to do all the drilling I wanted to do.
Seven hours later…
I didn’t finish everything I had hoped to, but I got most of it.
Mortises II