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This is not a major problem, but I recently encountered an issue in which I was drilling a medium sized hole, about 1.5", in a small piece of treated wood. The bit was a fairly new and fairly sharp spade bit. I clamped the wood, but the electric drill kept yanking itself out of my hands. When I was done, my hands were sore and the hole was so ragged as to be almost useless. I've searched various places for the answer, but I am not sure how to word my request so as to get the information I want.

So I guess the question is this: How do I secure an electric drill sufficiently to make a smooth hole? Is my only solution a drill press?

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    Were you using the extra grip for high-torque applications?
    – user5572
    Sep 30, 2020 at 22:19
  • FFR, 1.5" isn't really a medium-sized hole. That's sizeable. Anything over an inch/25mm is classed as a largeish hole in wood. Now obviously "fairly sharp" is a little subjective, but it could easily not be good enough for a spade bit/flat bit, which often don't have great geometry.
    – Graphus
    Oct 1, 2020 at 7:15
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    ...and the hole was so ragged... Spade bits are probably the reason that forstner bits were invented. Spade bits are great for blasting holes in studs for wiring and such, but if you want a clean hole a forstner or sawtooth bit is a better choice.
    – Caleb
    Oct 1, 2020 at 13:46
  • @Graphus -- I actually called it largish in my initial question, but backed off. And I used the term "fairly sharp" because it had never been used, though it was about a year old. But thanks for the info.
    – MJB
    Oct 1, 2020 at 13:47
  • @jdv - no, my drill does not have an extra grip.
    – MJB
    Oct 1, 2020 at 13:49

1 Answer 1

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It sounds like you're running your bit too slowly. Spade bits are pretty sensitive to low speeds. A faster speed (and less feed pressure) will result in less material being removed with each pass. This, in turn leads to less force on the wood, resulting in less tearing of the fibers. This tearing of the fibers, instead of cleanly cutting them, is what causes the ragged hole, and the ragged hole is what causes the catching.

If your spade bit has a "snail" (a lead screw that pulls the bit into the wood) you won't be able to slow your feed. I don't recommend this type of bit for woodworking.

Another possibility is that you're not maintaining a consistent angle while drilling.

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  • Yes this, but I'd bet sharpness is an issue. It seems not just many but most spade/flat bits aren't as sharp as they could be straight from the factory. OP, give the 'wings' a quick honing (you can use a fine metal file for this if it's all you have) and along with this tip about speed and feed rate see if you don't see quite a significant improvement in drilling ease and hole quality. Despite what people nearly universally think, you can drill a hole nearly as clean with a spade bit as you can with a Forstner, if the geometry is good and it's very sharp.
    – Graphus
    Oct 1, 2020 at 7:18
  • @Graphus -- I will give it a try. Thanks.
    – MJB
    Oct 1, 2020 at 13:48

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