Bore into end grain

[Bob Jones 5443]

Not true!
Using a Milescraft Drill Mate as I mentioned & linked to above (or the crazy expensive Woodpecker's) will allow you to use one.

Yes, but I’d prefer to just use a guide block and a drill. I don’t really want a drill press alternative in the shop. I don’t often need precision boring into pieces that don’t fit on the drill press.

Plus, no offense to the Woodpecker fans, but I’ve never felt the urge to pay their prices — although their tools are visually appealing and probably work quite well. Kind of a Bridge City Syndrome.

[Bert McMahan]

I’ve been coming around to that, as it would ensure no face-to-face misalignment. I’ve also considering screwing guide block to the two outside boards to also eliminate side-to-side movement while I drill. I think that’s what I’ll settle on.

Using a drilling guide (DIY or bought) means I can’t use a Forstner bit (shaft is narrower than cutting head), but my brad points are pretty sharp. Worst case, I buy a new bit for the end grain. With this method I’ll get a preview of how the bit does in the same end grain before I go into the work piece.

To get the shank holes on the guide, I’ll hold the part in a Jorgensen hand screw and lock the hand screw down to the table.

Thanks, everyone!

If you're dead set on a forstner bit, drill your guide hole to the shank of the forstner bit. Cut out a recess at the "output" side of the drill guide with a bandsaw or something. Thread the forstner through the guide, then clamp it to the drill. Last, push the guide block up against your workpiece. The forstner will be trapped between the guide and the workpiece and will be guided by the block the same way.

[Bruce Wrenn]

If you're dead set on a forstner bit, drill your guide hole to the shank of the forstner bit. Cut out a recess at the "output" side of the drill guide with a bandsaw or something. Thread the forstner through the guide, then clamp it to the drill. Last, push the guide block up against your workpiece. The forstner will be trapped between the guide and the workpiece and will be guided by the block the same way.

Plunge router, guide bushing with up cut spiral bit, easy peazy!

[Warren Lake]

Kent answered your question. If you are worried about your brad point learn how to sharpen them. We were taught to make brad points out of regular twist drills and they cut excellent but a bit of skill as you are making a bit instead of sharpening an already made bit. If you have lots to drill then do Kents set up and put hardened drill bushings in.

[Floyd Mah]

Forstner bits are basically very short (1/2" or so) bits and can be used to make holes with a gentle curve if you put radial pressure on the bit as you drill. For this application, it's probably fine, but for a deeper hole, I would prefer a bit with a longer dimension to aid in keeping the hole straight.

[Bob Jones 5443]

Epilogue. After several trials and errors with various drill bits, I ended up using a plunge router. The task was to bore 3/8” holes 5/8” deep into end grain in a 7/8” thick bubinga board. The work piece is 42” long, so it even stuck way up out of the shoulder vise. A little too high for stability.

I used the Young Je mortise jig I’d made a few years ago, tightly clamped to the board, which was held fast vertically in my Moxon vise — just a few inches above the vise. The routing was trivially simple (zip zip with a 3/8” all-carbide up-cut bit), but devising the setup was a head-scratcher.

By the way, the Rockler threaded inserts were not up to the job. They buckled like a tin can in the test parts. I went with stainless inserts from McMaster Carr. The spec says to use a 3/8” bore, but the inserts weren’t going to chew into even that. Bubinga is hard! So once I had clean 3/8” bores, I Skill-drilled the holes out with a 27/64” Brad point bit, and even then I needed to take my time tapping the inserts in — backing out and in until reaching the depth.

Sincere thanks to all for your good old fashioned SMC ideas and advice! I can always count on this community to come through. I more or less ended up using Bruce Wrenn’s plan, but your suggestions carried me along through the iterations leading up to the eventual operation.