Forstner bit recommendations

[DGDevin]

I have a project requiring a dozen 2" holes through a piece of 2" laminated pine--actually two pieces of 1" laminated pine but drilling them together seemed like a good way to ensure the holes would line up. Not having a Forstner bit that large I bought a Woodcraft house-brand bit for ten bucks and fired up the drill press. I got maybe half a dozen clean, easy holes. After that it got rough, lots of tearout, not so pretty.

I'm sure that buying a more expensive bit would have produced better results, a better grade of steel and so on. But how much better, where is the point of diminishing returns? Would moving up to a $20 CMT be a real improvement or is a bit in that price range likely to be from the same source as the house-brand bit? Is spending $40 (or more) on a Famag or Bormax going to give me four times the performance of the cheap bit or is a significant fraction of that price in the brand name/marketing? What's the magic price range at which performance goes way up but doesn't irritate SWMBO beyond the redline?

[Toe Dipper]

I bought this Porter Cable set at Home Depot and have been pleased so far.

it was ~$40 at Home Depot.

[Swingman]

"DGDevin" wrote

In my experience with that particular brand, absolutely ... and more.

[Norm Dresner]

If all you need are "holes", I'd use a hole-saw because it's got to actually remove far less material than a Forstner bit. Another possibility which would make Forstner bits last longer is to drill a, say, 1-3/4" hole with a hole saw and then clean it up with a Forstner bit.

Norm

[Leon]

Before answering, I must say that even for a "cheap" bit you got poor mileage. HOW FAST are you spinning that bit? You should be drilling at 400 RPM or slower or you may over heat the bit and cause it to dull prematurely.

I have an old set of Trendlines Forstner bits make in Germany that have been well worth the bargain price that I paid. The 1-3/8" bit alone has seen probably a thousand holes in Oak, Poplar, Pine, Maple, Walnut, and "MDF".

The better brands will last you longer but make sure you are drilling at the correct speed.

[DGDevin]

I was at 600 RPM and kept a light touch on the handle. Took plenty of breaks to let the bit cool down and to vacuum away chips and dust. Hmmm, I'm not sure my old Skil press goes that slow. Thanks.

[DGDevin]

Interesting idea. I used a Forstner because I've had good luck with nice clean holes using smaller bits and I don't mind saving time on sanding something smooth, I also wanted the holes to line up real straight and I find it easy to get a hole saw just a hair off-center....

[SonomaProducts.com]

[Gerald Ross]

When I'm drilling large holes I start with the large forstner and drill about 1/4 inch to make a good guide rim, then drill out the center with a smaller bit. Then go back and finish with the large bit. On the drill press it should be easy to drop back into the shallow hole and finish. There will be less heating and lest stress on the large bit.

[barker7]

Have you tried sharpening the bit? It's very easy to do with a small file or one of those diamond "paddles".

I just sharpen the two "shavers". I don't bother with the rim. If it was a cheap bit, it may not have been sharp to begin with. So next time, if you sharpen it, it may last much longer.

I just recently made about 12 motises in pine that were about

1"x5"x1.5" deep. I leaned on the drill press feed pretty hard. Lot's of nice shavings and no burning. (it was actually a very pleasant smell). It was a cheapo bit of unknown origin.

[DGDevin]

I gave that a try yesterday, and I was able to restore the "shavers" a bit. However the tear-outs that concern me are around the edges. The bottom I don't care about so much, that part disappears, it's the sides of the holes that look bad. I think the bit started off nice and sharp, the first few holes were clean as a whistle. I might use a router to clean up the edges, it's going to be one of those "educational" projects....

[DGDevin]

You, sir, are a genius. I might even do something like that using a jigsaw for the middle step. Thanks.

[Hoosierpopi]

link is for Lee Vally HSS "Brad Point" bits. I bought three of these (they ain't cheap!) and love 'em. They came with that green plastic coating on the tip - necessary! When I pulled the coating off the half-inch bit, I cut my finger (nice, smooth cut) they are that sharp to begin with.

My Forstner bits are not of such fine quality, save one 35mm I spent $14 or do dollars on. And I can notice the difference between the Good and the Ugly. If I had a project needing a 2-inch Forstner, I'd look to Lee Valley Tools.

They have a comparison chart at

might help answer some of your questions.

And I want to thank the fella who suggested the 400RPM - I'll have to try slowing things down a bit next time and may find even better performance!

They have a Forstner/Saw Tooth Bit "2" 06J71.32 $16.30"

would try that one

Forstner-pattern bits are used wherever edge-holding ability is needed, such as in the overlapping holes of a mortise.

The razor rim allows the bit to hold perfectly, even if the brad point is over a void. Since the rim is several thousandths of an inch higher than the chippers, the bit enters cleanly and the double chip channels clear well.

The bit gives a cleanly cut, flat-bottomed hole ideal for plugging. A primary use for this bit in the woodworking industry is to drill out knots for later plugging.

Saw tooth bits (usually over 1" in diameter) are primarily for use in a drill press. They are most useful for boring smooth, clean holes in all wood varieties at any angle. The double chip channels are less subject to rim heat than forstners and are easier to sharpen. Although their edge-holding ability in overlapped holes is slightly less than forstners, the difference is negligible in drill-press use.

[DGDevin]

that might help answer some of your questions.

Heh, I own the issue that includes that review, but I thought I'd seek personal experiences since sometimes those are more valuable than magazine tests for some reason.

I've discovered my old Skil drill press bottoms out at 620rpm, I wonder if I can find a different pulley spindle that would give me a lower range of speeds? Thanks for the ideas.

[Martin H. Eastburn]

Look at the motor. What speed does it have. You might be able to find a slower speed. One never knows without looking.

What is really needed is a third cone to step down more. Or a 3 phase motor and a 220 to 3 phase box that is a speed control as well.

Mart> Hoosierp>

> that might help answer some of your questions.