Can anyone tell me a good source for 2" auger bits? It seems like not too many people make them anymore. I heard that you can get them from Irwin but only by special order. Has enyone teied using a milwaukee or dewalt self feed bit to rough out a mortise? It seems like they may stay sraighter than an auger and can easily add an extension. I am also thinking about trying to use my drill press with an adjustable stand for the beams. Any thoughts?

getting a big hole to maintain desired alignment when you drill is a challenge. Augers tend to make their own path in some woods. Shipwright bits of good quality can be controlled somewhat easier in a heavy weight drill. Cutting a 2" hole for your mortise followed by a square corner chisel may save a lil time but you are crowding the usual max dimension of the mortise.
In really heavy stock a set of clamps, a metal frame and a large electromagnet jig holding the drill (kinda like a portable drill press) has been used to keep the holes straight when boring thru for pegs. You may find a picture of this on the Franklin Farm project file.
Whatever keeps you in control is what works best.

Try Jim Rogers "tools for sale" post in the tools forum.

Regarding the self feed bits: You'll be forever pulling the bit out to clear the chips. Then you have to get the screw tip restarted in the hole. While trying to minimize the number of pull-outs, you inevitably leave it in too long, and the chips will jam, and you'll be pulling them out with a needle nose pliers. DAMHIKT.

CB.

I was taught and it has been my experience to not attempt to clear the chips while boring a mortise. The spiral twist of the bit should clear the chips to the surface of the timber, even in oak.
Once a bit has started it path to the bottom of the mortise, it should not be stopped and removed to clear chips for the mentioned reason "you have to get the screw tip restarted in the hole."
Using a boring machine with the proper sized bit for the mortise is the key.
Once the bit has reached the bottom of the mortise the handles of the boring machine are turned in reverse to "back out" the lead screw tip from the thread it has created in the bottom of the mortise. This turning in reverse one full revolution of the handles will back out the tip and then you engage your lifting mechanism to lift the bit and all current chips out of the hole.
We recently repaired a shear pin on a boring machine due to the operator not understanding this procedure (or old age of the worn shear pin).
Understanding how to use this tool is important.



Hope this helps.

Jim Rogers

My point exactly. The "self feed" bits that Topshelf was referring to are shaped like a forstner bit, but with a screw tip. They have no auger to clear the chips. CB.

Thanks for all the input. I was thinking about trying to build a cheap man's modern style beam drill using a drill guide or possibly using my drill press since I only have 3 or 4 posts that I need to drill mortises in. Anyone here done that?

I wouldn't try the drill press. It is easier to carry a drill to a post than a post to a drill.

For that many mortises have you considered using a t-auger? If it is sharp, it cuts well and the slower pace allows good control.

Aside from that, I would get a 1/2" drill with a big long handle out the side and a clutch to prevent injury and a 2" auger bit and make a guide to show you square in 2 directions and drill them that way. (I simply screw 2 1x6's about 7" long together in an L shape making sure the ends are cut square and then place it where the bit is in the corner as I drill the hole--it's a cheap, quick drill guide).

Or you could get a boring machine like the one in Jim's photo. They work well.

The self-feed bits such as plumbers/electricians use are practically worthless for drilling mortises because as daiku said they don't clear chips.

Also, I wouldn't worry about the bit wandering when drilling to typical mortise depth. Your chisel can make quick work of correcting any slight misalignment. I would drill any through mortises from both sides, though.

I wish I had a good source for a 2" bit, but I cut the end off a T-auger to get mine.

Good luck,

Gabel

I actually bought a 2" Vintage bit off of E-bay that has a square end. I may try to cut it off and use it in my drill. It has large gaps between the augers unlike the ship auger bits of today. My concern is that mine only has a single cutting edge which I see many old Beam drills have. I see that some of the older 2" bits have 2 cutting edges. It seems like they may stay more true and not wander. I guess I should look for an old beam drill...

I'm not familiar with the types of bits he was intending to use, that's why I posted the caution........