Forstner bits

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I wanted to counterbore several 3/4" holes about an eighth of an inch deep in 3/4" plywood. I bought a set of Forstner bits at Lowe's, chucked the 3/4" one in a corded 1/2" drill, and made a practice swipe at a piece of pine. It was incredibly hard going. I really had to lean on it. I did manage to get down to about an eighth of an inch, both in the pine and eventually in the plywood, but I don't know what it would have taken to drill all the way through. I tried several diameters and they were all the same.
Did I get a crappy set of bits, or are they not meant to be used in a hand drill? I don't have a drill press to make a comparison.
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It's just about impossible to hold your hand drill at exactly straight up and down anda forstner has to be absolutely straight to cut. I've been able to do it by slightly altering the angle a little bit, all the way around the compass.
With a hand drill it's a royal pain. You can get better results with one of those hand drill guide jig things that essentially make your hand drill into a little mobile drill press but it's still a royal pain. Sometimes it's the only way, though.
And yes, those lowe's bits probably aren't all that sharp to begin with. My sister gave me a set one Christmas. It's nice having all those sizes but every time I have to drill a lot of holes I end up burning out the bit and buying one that costs about as much as the set.
Still, it really is nice to have all those sizes and they work if I don't push them too hard. :-)
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Eh? No. I drill angled holes with forstners all the time. -- Doug
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wrote:

It depends on your skill level and experience.
Many years ago I made rustic furniture. It was all made of planks held together with lag screws and large bolts. All had to have the pilot holes drilled and the head set beneath the surface.
I drilled hundreds of holes with a hand drill almost every day. I got very good at drilling straight holes. So good, I used to make a little drinking money betting people I could drill holes as straight as they could with all their fancy guides. (And I did it much faster too.)
I am certain that I lost some of that ability, but I can drill a pretty straight hole to this day. But I had lots and lots of practice. I ain't no woodworking natural or athlete. Just worked at it awhile. Like anything, if you do it enough, it looks easy and/or natural.
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It doesn't have to be straight to cut, as it will cut at any angle. And it will cut less than a full circle.
It will do both of those nicely in a drill press. In a hand-held drill, if the bit is not perpendicular to the work, and if the bit lacks a substantial center point as most Forstners do, it is susceptible to skating. The rim contacts the work on one side, and the bit tries to walk away on the rim. Once the hole is started, it's fine.
John Martin
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snipped-for-privacy@gmail.com wrote: ...

No, that's one of the advantages of a Forstner--it is guided by the rim and can do things like angle cuts, one side off the edge of the material, etc., etc., that others can't do.
It does take a good quality bit which is both sharp and primarily runs perfectly true, however, and many of the inexpensive ones simply aren't finished well enough to do so...
--
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dpb wrote:

I second that and what Lee Michaels said in a previous post. I built a platerack last winter that used 60 1/2" holes for dowels. I don't own a drill press but used a Freud Forstner that drilled the holes nicely. As Lee said, it takes a bit of skill which needs to be developed, but once you do that, the holes came out as well as I wanted.
Tanus
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says...

Get a self feeding bit, they have a small screw thread to pull the bit through. I just bored some 2 1/2" holes through railroad ties, and it pulled through faster than I wanted. I used my Harbor Freight copy of the Milwaukee Hole Hog, one of the best HF tools I have bought. Terrific torque. I use self feeding augers for boring holes for electrical wiring, using the HF sideways in between studs, and you don't even have to press, just touch it to the wood and hold on.
--
Dennis


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I think you already know the answer since you typed the above. Even a cheap set at Woodcraft is sharp enough for a few holes.
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Was it turning in the right direction? Are you sure?
John Martin
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FOstner bits are not made to be used a high RPM. Check the bit, it should have some info about max rpm recommendations. I found this out the hard way.
John Martin wrote:

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Yes, and yes.
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I found myself having to make a 1.5" to 2" adapter ring tonight, and used a forstner bit and hole saw to do it, in a scrap piece of full 3/4" birch ply. Since I had the forstner bit out and I remembered your post, I chucked it up in my dewalt drill afterwards.
I clamped a scrap 2x4 stud cutoff to the bench, and in about 60 seconds (and much swearing/trying to keep the bit perpendicular) I managed to make just over a 1/8" impression.
By comparision, drilling completely through the ply took about 30 seconds at 580rpm on the drill press. (Probably could have done it faster, but I just kept even pressure and backed out occasionally for the waste.)
So.. my answer is "No, they ain't ment to be used in a drill."
(For reference, I was using a Rockler steel - not carbon - forstner bit.)
Jason Buckler Marietta, GA
Richard Evans wrote:

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Richard,
I don't wish to seem contrary to other posters here... but a forstner style bit can easily be used in a hand drill. And I said "forstner style" because there are a few configurations of bits on the market commonly referred to as "forstner". My guess is that your bits are not sharp. I purchased a set of Chiwanese made bits from Harbour Freight (24 bits in a wooden box for 20 bucks) that couldn't cut cheese. That is, until I sharpened every last one of 'em. You can sharpen them with a fine toothed round file and a fine grit stone (for the circumference). Diamond hones and India slip stones work well too. And lots of patience!!! (especially for the small ones). After sharpening, they cut like butter. Except not for long. The steel is low quality so they don't hold an edge very well. Also, use a slow speed to keep friction to a minimum (variable speed drill) and try to stay as perpendicular as possible.
To really appreciate how well a "forstner" bit can cut in a hand drill, invest in a Freud bit. They're sharp right out'a the box.
But there's no denying that a drill press works best.
Cheers.
Michael
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They're not meant to be used in a hand-held drill only because there is no central point to locate the bit. If you don't hold them perfectly straight - and sometimes even if you do - they can skate all over the workpiece.
It shouldn't take any great amount of force to get them to cut.
I presume you're referring to a steel bit as opposed to a "carbide" one.
John Martin
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"John Martin" wrote

Then your not talking about a "Forstner" bit ... proper Forstner bits indeed have a point, which is called the "gimlet point", as named by the man who invented the bit.
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Oh, I most definitely am. The Forstners I use are almost all by Connecticut Valley, BGI or PM - companies that have been making them for well over 100 years. Machine shanks and bit brace shanks. Some have small points that extend below the rim, some don't. On none of them does the center point extend more than about 1/16" below the rim. Of those that don't, some never did - it's not a re-sharpening mistake. The Forstner bits are meant to be guided by their rims, not their center points.
I even checked a couple of really big Forstners I have - 2-5/8" and 2-3/4", 3/4" shanks, about a foot long. Conn Valley, but they don't show them in their product list anymore. Original factory grinds. Each has a central point, but it's flat-topped and about 1/4" wide - it's certainly not intended to guide the bit.
With the brace bits, one trick is to turn them backward at first to get the rim to dig in slightly before you start to cut.
I've got no idea what was in Benjamin Forstner's original patents - all I know is that the companies that have been making them from the beginning have been making them without center points large enough to significantly guide them. They do help in getting them on the center mark, but that's about it. If you had a gimlet point, you wouldn't get a flat-bottomed hole, would you?
John Martin
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wrote:

bit.)
indeed
Don't be so naive. Just because someone calls/sells a bit as a "forstner", does not make it so.
Once again, a true "Forstner" bit, BY DESIGN, has a point to guide the center of the initial drilling. This is an inarguable FACT, deal with it.
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Swingman wrote:

Not in the original patent, but others dated later do have the point. Ben sure liked drill bits!
(I hope the link works)
<http://www.google.com/patents?id=FtRDAAAAEBAJ&pg=PP1&dq NJAMIN+FORSTNER&source=gbs_selected_pages&cad=0_1#PPP1,M1>
MikeB
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"bq340" <wrote

He called it a "gimlet point" and it was added specifically to aid in centering the bit for drilling.
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