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I have a cheap set of DeWalt twist bits (they are gold (the color, not the metal!)). Whenever I use bits above 1/4", no matter the wood I am drilling (even pine and 2x4s), I will get partially through the hole and the bit will "catch/snag/not sure what to call it" and very forcefully force the bit down into the hole. That is, rather than cutting a way the material, it kind of punctures it and drags itself and the drill through. It is as hard to explain as I thought it might be haha. The bits are only very lightly used, so I don't think that "they are dull" is the problem, but I suppose I don't know how to test that for sure.

I do have some other bits and they cut through the same materials with no problem (and they are also very cheap twist bits, Irwin I believe).

Any ideas of what could cause this/what is wrong?

Thanks!

David
 

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Sawdust Creator
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The bit is just feeding itself downward...the bigger the bit, the harder it will pull in as it takes more force to cut off what it's pulling against. Sharpening can help...drill bits are by no means sharp from the store.
 

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Half a bubble off.. {Θ¿Θ}
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I "try" to use brad point or forsner bits on wood. Twist bits are held for aluminum, steel etc. They just don't cut clean enough for my liking.
Paddle bits may be ok if ya want to run a wire thru a wall for a cable tv run or some cat 5 wire but aside from that I have no use for them.
Buy & try some brad points.. You'll see what we mean.
..Jon..
 

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Using one of your larger bits, look at the web angle at the end. If the web top tilts greater than 15 degrees to the right it has too much rake angle which causes it to be aggressive and grab.
 

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As an X machinist I can say with fair certainty that the problem is that most twist drills are designed, angled and raked for drilling standard ferrous metals. Every metal requires a different angle and rake. As has been pointed out, when using theses drill bits in wood they will feed themselves down, it usually helps to drill pilot holes first. Wood boring bits are a better option or Forstner bits.
 

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Mine do the same thing. since I know about it i'm ready for it. Hold onto the drill and take it easy. Once it grabs pull it back a hair and let it catch up. Then go slow again. With practice it can kind of be controlled. Like the other guys are saying though, brad point bits would be ideal. I just haven't invested in them yet.

If jigs and tools were chairs and stools, we'd always have a place to sit.
~Stumpy Nubs
 

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Old Methane Gas Cloud
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Those drill bits are "construction" drill bits. Great for drilling large quantities of holes fast with little concern for quality.

I have a couple of sets also. I only use the drill bits in the drill press.
 

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Old School
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I "try" to use brad point or forsner bits on wood. Twist bits are held for aluminum, steel etc. They just don't cut clean enough for my liking.
Paddle bits may be ok if ya want to run a wire thru a wall for a cable tv run or some cat 5 wire but aside from that I have no use for them.
Buy & try some brad points.. You'll see what we mean.
..Jon..
+1. :yes: Brad poiunts work great with wood. If you use a twist drill bit, pay attention to the degree of the point. For metal work, 135° is suggested, as they are less likely to skate, than a 118° which are intended for wood.






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George has the answer for your problem... or drill a small pilot hole, bore half way down, flip the board over, and follow the pilot hole from the bottom side and meet in the middle. This flip flop method works best with larger pilot holes, that is to say if I'm drilling a 1/2" hole, my pilot is going to be 1/4" with a little tear out, but that gets chewed out with the 1/2" bore on the flip side.
 
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