# Sharpening Forstner Bits



## Jim Jakosh (Nov 24, 2009)

Does anyone have a slick way to sharpen Forstner bits? Like which way to you sharpen the flat area and what do you do to sharpen the teeth around the edge?


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## KnotWright (Nov 6, 2008)

I did a quick search online, here's a few good examples for you:

http://www.wwch.org/TechData/Forstner_Bit_Speeds.jpg






There are a lot of other pages on this topic, but these two actually show two different methods of doing it.
I tend to use the first method, since it only requires a few tools.


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## AJswoodshop (Mar 2, 2012)

Jim,

I have never sharpened my Forstner bits. But, I thought I heard my Grampa say that you could sharpen them on a drill doctor. Not sure thou, I love my forstner bits, I got them at a auction for only $9 dollars! It's a 20 piece set!

AJ


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## HorizontalMike (Jun 3, 2010)

Rat tail files come in handy here. Finer toothed, better "sized" for bit sharpening, and easier to control IMO. And I try to only minimally sharpen at any one time, in order to keep as much of the bit as I can. In this sense, I sharpen more frequently but less aggressively.


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## Jim Jakosh (Nov 24, 2009)

Thanks, James for this info, that is what I thought. I have been sharpening the flat with a diamond hone and will now try to uses round stone on the curved area.

AJ, I have see a drill doctor and they tend to sharpen just the point of a drill and do a back cut to thin the point for less resistance when drilling without a pilot hole. I don't thin they would address the surfaces of a forstner.

Hi Mike, they must not be too hard if a file will cut them. I'll have to try that too. That U tube video was a good one but it showed a big one being sharpened. The ones that get dull the quickest are the 3/8, 1/2 and 3/4. I use them the most- especially the 3/4 one. I try a file to all the surfaces of the 3/4 one and see how it works!!
thanks, Jim


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## HorizontalMike (Jun 3, 2010)

While I do not know, I do suspect that some of the cheaper Forstners are made with softer steel (I am NOT saying SOFT) than the highest quality bits. As a hobbiest, I just do not use them so much as to need to buy the best, though I understand that desire to have the latest/greatest at all times urge.


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## Jim Jakosh (Nov 24, 2009)

Hi Mike. some say HSS but it may not be hardened High Speed Steel. that makes a big difference!!


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