Does anyone recognise this type of drill bit?

southern_guy

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Jul 17, 2007
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I can't recall where I picked it up, probably from my father. It drills a very nice clean flat bottomed hole (despite the rust). I would like to find some more of this type but in a slightly larger size.

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Yes, I've seen them before.  I can't remember what they are called.  They are similar to the "greenwood bits".
 
I believe you are looking for a center bit. Usually the point in the middle has a screw thread, but sometimes not, as in this case. These bits were commonly used with hand braces which is why you do not find them easily any more as hand braces are uncommon.

Richard.

 
Just looked in Clasic Hand Tools by Garrett Hack  and as Richard said its a centre drill
 
southern_guy said:
I can't recall where I picked it up, probably from my father. It drills a very nice clean flat bottomed hole (despite the rust). I would like to find some more of this type but in a slightly larger size.

Lee Valley Tools sells a version of these bits.
http://www.leevalley.com/en/wood/page.aspx?p=46261&cat=1,180,42240,53317&ap=1

If it's clean cutting centering bits, then the modern day equivalent is brad point bits. If it's edge holding capabilities and flat bottom holes you're looking for, then Forstner bits would be your choice. But, Forstner bits are more of a specialty bit and the edges on them lose their temper and sharpness quite easily if misused. All in all, your best choice would be the brad point bits. Depending on price, they come in steel or carbide point versions, with the carbide being the more expensive.
 
Depending on what you are drilling, you could use an antique Center Bit, one of the Chinese Power Bit clones or a Greenwood Bit from Lee Valley tools.

Center bits are often in the price range of one dollar to a few dollars, are easy to use and fit any hand brace you own.  They are real nifty and work the first time every time.  They are also easy to sharpen.  Since the drill shank is soft, you can cut off the square end, chuck it in your T15 and drill at low speeds.  They were offered to the nearest 1/16 inch, but this measurement was sometimes loose, so you can build a set to the nearest 1/32.

The Chinese clone power bits aren't always straight and don't work as well as the old Stanley's, in my opinion.

The Greenwood bits are available at Lee Valley: http://www.leevalley.com/US/wood/page.aspx?p=46261&cat=1,180,42240,53317&ap=1

Gary Laroff
Portland, Oregon
 
thanks for the input. I guess I can stop looking. The greenwood bit, according to its description, is not good for hardwood. I was intending to drill into mahogony. I will try a forstner bit.

 
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