Question - Brace and Bit Chuck

[Mike Ellis]

Here's another question from the wayback machine for you tool experts out there. When you're using a brace with the old style chuck that accepts the tapered square bit heads, is there a guideline for how far the shank should be dropped down into the chuck before tightening?



OK guys, I can hear you laughing out there, try not to choke yourselves :-laf :-laf :-laf --- but it's not a completely off the wall question. The way the chuck engages the taper, the bit can be inserted anywhere from "all the way in" to "just flush with the chuck opening". Inside there are usually a couple of notches that look like they should engage the top of the shank, but the engagement is kinda iffy. It is not so noticeable with the short bits, but with the long beam augers it can produce a good bit of runout so the end of the auger wobbles around in a circle.



That kind of wobble is probably OK for Moe if he's using it to drill a few holes in Curly's skull, but it seems like a more rigid grip would be useful :-laf

 

[bmoeller]

Can't answer the answer, I'm afraid. Been curious how they work myself.

 

[ttbird]

I would experiment and place it where there is the least amount of runout. It would make sense that this is the correct inserted distance. Just my 2 cents. Use them sometimes when climbing poles at work. Our holes are not real critical though.

 

[Allnew2Me]

The size of the tapered end of the bit will vary depending on what it is, screwdriver, auger, etc. , or by maker. Turning it 90 degrees may affect fit also but just set it into the brace until it is evenly held by the jaws when you tighten it, the depth is not that important and it will usually self-center. If it wobbles it is in too far or not far enough. If you take the outer chuck off you will see that on the inside of the two jaws there is a corresponding tapered recess designed to accept the bit for a firm grip. You have to remember that these are not high speed tools and are meant to be turned by hand, but it is difficult to start a hole straight or drive a screw if the bit is not securely held. The notches you see are to enable it to grab a square shank bit.

 

[TRAMPLINEMAN]

When I was an apprentice they used to make us use them on every pole. Our bits were set all the way in. I hate those things. Hand drilling holes in poles when it's 100*+ out sucks!

 

[Mrudolph]

The notches you refer to lock the bit in to keep it from being squeezed out because of the taper.