Combination Drill/Countersink

[Eric Brown]

There are a bunch of drill/countersink combinations available. Most have one size drill bit that usually can be adjusted. You need a set to cover the typical ranges used in woodworking. Some drills are tapered, some are not.

I found an interesting tool called "Coopers Countersink Drill Chuck". At a glance it looks like a common three jawed chuck. Looking closer the three jaws are sharpened into cutters. The chuck also has a hollow spindle allowing drill bits to be adjusted for depth. The hollow allows up to a 5/16" bit to be used. While the shaft is round, it can be used in either a drill press or a brace that can handle round shafts. This chuck was invented by Hugh H. Cooper of Troy, New York and is patent #1,294,054 (Feb. 11, 1919). Bored a hole and countersunk in walnut with a brace. Works very well.

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[Jim Koepke]

Interesting find Eric, thanks for sharing.

Now to find one for myself. :D

jtk

[Stew Denton]

Thanks for the heads up Eric. I've used a number of different types, going back about 45 years or so. That one looks pretty good. Wish they were still in production, but if they were they would probably be pretty pricy.

Stew

[bridger berdel]

ping Rob Lee...

something to resurrect.

[Jim Koepke]

Most of the modern drill/countersink bits have three steps. One for the countersink, one for the screw shaft and one for the threads. The "Coopers Countersink Drill Chuck" only takes care of two sizes, the countersink and the thread size. In many cases the shaft would likely cause the wood to split.

jtk

[Eric Brown]

Nothings perfect.

[Brian Holcombe]

Really nice! I have a separate countersink from LV and it is wonderful to use, doesn't tear out unless the wood is really nasty. This looks handy, I may have to hunt one down.