Thread: Auger slipping in brace

Sorry Soundwave, but those Irwin speedbores need a LOT of torque; hence why they are manufactured with a hex drive that can either go in an impact driver or are firmly located in a standard 3-jaw chuck. Even the best two jaw brace will only allow the bit to be held across two points which can work for smaller bits, but 32mm is way too big. Also, 4-jaw can't hold a hex bit firmly unless the pairs of jaws can be independently moved; the geometry is just wrong.

You can get hold of expansion bits which were made for braces:
bit.PNG

Thanks for the response! I guess this is the price of learning...

There are adaptors.
Tenon Cut Brace Adapter | Bit & Brace - Carbatec
Having pointed that out I should get some myself.
Regards
John

Welcome to the Forum, Soundwave.

CT's correct. For the two-jaw chuck in your brace really you need bits with tapered square shanks like these:




It might be possible for you to use your hex shanked bits in an electric dril if, repeat if, you can slow the revs down enough.

Hi all. I have a somewhat related problem. Using traditional tapered square shank bits in one of my dads brace drills (with ratcheting mechanism) I find that the bits sometimes work themselves loose. Is there an optimum depth for best holding power for the bits in the chuck? Can I tell if the chuck is at fault? Broken? Worn out? Thanks

Hi,

I found this video very helpful to understand how the two jaw chucks and the tapered bits work together and how to mount them in the brace correctly.

YouTube



Sent from my SM-G950F using Tapatalk

Thanks. Paul's video was excellent as usual. I don't think I was putting the bit in deep enough, so the jaws could encompass the the widest part of the taper.......obvious now I have seen it.

Originally Posted by soundwave

Hello everyone! This is my first post because, frankly, I have a problem.

I'm following along with a project I found online, learning a lot, and I've gotten stuck. I need to bore a 32mm hole through 90mm of pine and to do this, I bought a tri-flute Irwin speedbor bit - which is hex-shafted.
I put this into my four-jaw brace and couldn't get anywhere with it. The lead screw was making its way in but, the second that the flutes started to cut the wood, the bit would just slip and spin in the chuck. After a few attempts I tried the same bit in my two-jaw brace that was my grandfather's, with similar results. I got a little further with the two-jaw brace, but it kept slipping too (although this brace is not in the best condition) and I think I might have ruined the jaw in the process.

Before I tried this, I kept reading that people use hex-shafted bits in hand-braces without any issues. Does anyone have any advice? Is there a trick I'm missing?

The hex-shafted bits work fine in some braces, such as the North Yankee Bell System, made by Stanley ...



More modern braces may work in a similar way.

Failing this, you may get a different bit to work, such as a forstner. To use a forstner, which does not have a lead screw, first drill a pilot hole (try this with your hex bit as well).

Regards from Singapore

Derek

The other thing is to have a look at the v-groove in the jaws of the 2-jaw. One of my (+20) braces (OK I HAVE A BRACE PROBLEM) had the V worn down and filled with crud so it was more of a shallow U, and that caused slipping of the pyramid in the jaws. So undo the shell and have a close look at the jaws and tidy up the V groove if you can with a wire brush (to deal with any accumulated crud) and a file, or if that doesn't work, then replace them (you can buy replacement jaws from Stanley in the US, but I would just sacrifice a 'surplus' brace and take good jaws out of it to save a favourite).

The Irwin Speedbor Tri flute bit is designed to be used in a powered drill not a bit and brace, they are effectively a screw auger tip with spade bit cutting edges. They require very little effort as the screw tip will pull the unit through until the tip protrudes through the rear of your piece, you will then need to use some pressure to finish the cut. They will cause some tear out.
Ex Irwin employee of 25 years.

The Speedbore are only designed for use in a power drill because that is what most use these days. The "design" part here is simply the hex shaft. If you can fit the hex shaft to your brace, they will work very well. A couple of related points for interest ...

As mentioned earlier, I use hex shafted bits in my Bell Systems braces. Here is a picture of one being used ...





The auger bits in this photo are by Wood Owl, a Japanese company. These are tri-fluted and similar in this regard to the Speedbore. The Wood Owls are probably the best auger bits on the market, and better than the highly renounded Jennings, which I have used for many years.

Now you would not use a auger bit with lead screws in a drill press! One only attempts this feat once!! (The screws will pull the workpiece off the drill press table).

For drilling at the drill press, Wood Owl make an awl bit without the lead screw. These are marketed under the Star-M brand ...



Regards from Singapore

Derek