Brace and Bits (Repair)

[Don Emmerling]

I bought a brace and bits off of eBay and have some questions. The brace is fine but the bits are giving me some problems. The bits are sharp enough but the threads at the tip are not good looking. The crest of the threads on each bit are flattened, which means they do not pull the blade of the bit into the wood. Is there away of improving the bit threads to make these things work. I did not spend much for the bits so if they are toast it is not a big deal. Any help or suggestions would be appreciated.
Thanks,
Don

[Joe Bailey]

They are, most likely, not worth screwing* around with. Auger bits are abundant and cheap.

If you want to try and rescue these, your best bet is to painstakingly file the threads back into functional shape. A small cross-section taper file (or the like) is your best bet.

*pun intended

[Jim Koepke]

Don,

As is usual, pictures might help to convey the problem.

If you have a metal vise or make some scrap into protective faces for your wood vises it wouldn't be difficult to use a three corner file to make the threads usable. Do a pass or two on each thread and then give the bit a quarter turn or less if need be.

If nothing else, you should end up with bits that can do their job.

If you do purchase a better set, these can be relegated to being used in wood that may have hidden nails or screws or other rough work.

jtk

[Jim Davis]

I would start with a small sharp cold chisel. Back up the point with wood so you don't bend it. Then put the chisel in the groove at the edge of the mashed metal and parallel to the thread. Tap the chisel and forge the displaced metal back toward where it came from. When you have worked your way along the entire thread, then take a 3-cornered file and smooth things up. (Don't use a tapered saw file because the corners of those have too large a radius for cleaning up a thread.)

JIm

[michael langman]

If you can put the bits in a drill press or lathe that turns in reverse you can use a 60* file, and starting at top of thread,carefully file out the flat spots. Run the lathe or drill press at a slow speed.

[Jim Koepke]

If you can put the bits in a drill press or lathe that turns in reverse you can use a 60* file, and starting at top of thread,carefully file out the flat spots. Run the lathe or drill press at a slow speed.

I do not think this would work too well. Not only the drill press or lathe not having a slow enough speed, but the auger bit tang will be difficult for either to grip.

You could bore holes in a piece of wood to hold the bits and turn them by hand. This is where having an apprentice would be handy.

jtk

[Jim Davis]

Since my point was not taken, I'll suggest again that filing out flattened threads should be done only after trying to move the displaced metal back where it belongs. If filing is the first approach, that metal is just gone and the thread can't work as well as if the metal were cold forged back into position first. There is little enough metal in those pilot screws when new. It's worth trying to retain as much of the original size as possible.

Just my 2 cents. (OK, it was a nickle.)

[Stanley Covington]

Jim

Excellent point, and brilliant solution which I will employ from now on. This sort of golden nugget of wisdom (worth much more than a half-dime) is what makes this forum worth perusing. Thanks

Stan

[Mike Holbrook]

I have also struggled with older sets of auger... bits. These bits work well when they have properly formed sharp cutters, not so well if they do not. I have taken chair and bench making classes that required drilling large/long and numerous holes in very hard wood where the challenge proved exceptionally hard to deal with in terms of keeping drill bits sharp. I read an article by Schwarz extolling the virtues of Wood Owl Nail Chipper drill bits and decided to try one. The Nail Chipper is designed to, you guessed it, drill through nails, so it is very tough but not the most precise instrument. The issue I had with the one I bought was it did not work well with a brace. It even left a fairly rough hole when used with an electric drill, as Schwarz mentions in his Blog.

Fortunately, I also ordered a Wood Owl Ultra Smooth Tri-Spur Auger bit to try too. Despite the fact that the information about the bits suggested they were designed for use in electric drills, my testing revealed that it worked well in braces as well. I made inquiries at Traditional Woodworker, where I bought mine, they said they simply had no information on using them with braces. I now have 3/8, 1/2, 5/8, 3/4" versions and use them frequently in braces and electric bits. I took two to a chair making class at Country Workshops, where we had to drill many long holes through thick oak chair backs and seats. They ended up drilling almost all the holes in the seats for the class and are still going strong. Bits can heat up very fast, particularly in electric drills, when pressured to go through long holes in hard wood. Most bits dull fast when they heat up. The Wood Owls pulled themselves through large long holes with practically no effort where traditional bits took FOREVER and a day, even after Drew hand sharpened them! Drew Langsner was planing to order some for his next class as were several students. The Wood Owl bits are made in Miki City, Japan. They are made to a more exacting size standard of precisely heat treated and induction hardened steel that simply stands up to much more abuse. They are even comparatively light. A 7 1/2" bit size 3/8-3/4" costs $16-$17, which may not be cheap but very reasonable IMHO considering how well they work and how sharp they remain after hard use.