Forstner bits

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"Just because someone calls/sells a bit as a "forstner", does not make it so." I agree, but then I am so naive. If you bother re-reading my post, however, you'll see that the companies I mentioned were making Forstner bits well over 100 years ago, under license from Benjamin Forstner - the inventor. That's not a Forstner bit?
Someone else has already posted a link to Benjamin Forstner's patent - # 115148, dated August 15, 1874. Rather than make you search for it, though, here is a quote from it:
"The circular band serves to guide the bit accurately in its movement, and also give the hole that is bored a smooth and perfect finish. By its employment the gimlet-point may be dispensed with, and as the cutting lips do not project beyond its horizontal plane, it follows that the wood is not cut beyond the line operated upon by the circular cutting-edge of the band."
And that, Swingman, is an inarguable FACT, with which you must deal.
John Martin

"John Martin" wrote
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I stand corrected ... mea culpa.

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Takes a man to say that, Swingman. Pax.
I'll admit myself that I didn't know of Ben Forstner's later idea of a center point. I've never seen a Forstner with one large enough to keep it on center. I have sawtooth bits with large center points, but I wouldn't call those Forstners.
Of the Forstners that I have that do have the center points, they are handy in visually centering a spinning bit on a mark, but that's about it.
John Martin

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The link is to an Feb 26 1886 patent which Benjamin Forstner clearly felt was an improvement and DOES include a cutting-point. A quote is under. So you are both right
In the manufacture of in improved auger the slots b are formed by milling, thus facilitating the manufacture and lessening the expense which necessarily attended the manufacture of the bit made under my formerpatent. 1. In an auger, a circular peripheral cutting-edge formed of two parts, a a', each provided with a cutting-edge, e, inclined slots d, formed in opposite sides of the cutter, cutting-lips b,formed along the inclined slots, and a central cutting-point, e, joining the cutting-lips b, substantially as herein specified

Swingman wrote:
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I'm quite certain I'm talking about a Forstner bit, and even with the center point, I still had skate issues.
These are the ones I was using, straight from the Rockler store in Sandy Springs, GA: http://www.rockler.com/gallery.cfm?Offerings_ID 954&TabSelectÞtails
They have they point. They are forstner bits.
Yet, I had skate issues when the main body dug in, all probably due to RPM speed. My Dewalt doesn't have a lot of inbetween (14.4V 1/2" chuck, older model. It's either not enough, or too much.)
That was my experience. I'll stick to using them in a drill press.. OR using them in a different drill.
Jason Buckler Marietta, GA

"Jason" wrote
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If they skate on you out of the box, what you're experiencing is mostly the result of poor quality. Not surprising as Rockler's hardware quality seems to have suffered since the advent of importing.
Next time you need a good Forstner of modern design (with the center spur), try the "Bormax" or "Famag" brands (you can now get both from WoodCraft):
http://www.woodcraft.com/family.aspx?FamilyId 17
http://www.woodcraft.com/family.aspx?FamilyIdw8
The "Bormax" are a bit pricier (no pun intended) but have served me and I've used a ton of forstner bits, particularly the 35mm variety for drilling cabinet door hinges. The one I have now has drilled a couple of hundred cabinet doors and will still cut you when handling it.
Famag was best of breed in a fairly recent FWW review.

Swingman wrote:
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Cool, appreciate that info. I don't often find myself needing forstners (I'm just getting back into the swing of things, as it were), but the next time I need to do a bunch I'll invest in a couple of those.
Thanks!
Jason Buckler Marietta, GA

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Skating seems to be a probelm with many brands of cheap Forstner bits. Oddly enough, this is one area where price really does seem to follow quality. Connecticut Valley, Famag and a couple of others have pretty much traditional patterns, but don't skate--if they're kept sharp. Some who wants to pay 30 or 40 bucks for a 16 bit set, should expect poor to fair (if they're lucky) out-of-the-box performance that improves with sharpening, but never equals, or even comes close, to the performance of the high end bits.
Famag is new to me, but ConVaCo bits have been around since I started messing with wood back in the early '50s. Jeez. No wonder the kids seem to be aging.

"Charlie Self" wrote
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IIRC, Famag is Austrian/German ... same inventive European engineering that is responsible for 99% of civilization's technological advances in the past few centuries.

I have these:
http://www.rockler.com/product.cfm?page 283&filter=forstner
they work great for me, and are opn sale right now for 60$ (The other set here is 70
shelly

On Jun 29, 11:56 pm, snipped-for-privacy@verizon.net wrote:
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Wouldn't carbide be better than those for hardwoods?
Darren Harris Staten Island, New York.

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these are!

On Jun 30, 11:58 pm, snipped-for-privacy@verizon.net wrote:
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Not according to the post: "Pre-sharpened high carbon steel bits".
I was going to pick some up.(They are not on sale anymore anyway).
Darren Harris Staten Island, New York.

not sure.... I thought that is the same thing....
In any event, this set works fine for me. - and I have all the sizes In need. If I ever burn one up, I'll get a freud.
shelly

Swingman wrote: > If they skate on you out of the box, what you're experiencing is mostly the
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I picked up these Grizzly bits ($30 for 16 pc. set) after a magazine review. It may have been FWW but I can't remember.
I've no complaints about their performance, and the price is very reasonable.
<http://grizzly.com/products/Forstner-Bit-16-pc-Set-Ground-Tips/H6334>

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I have a similar cheap set. For the sizes that you only drill with one or three hoes a year, they are good and it is handy to have those sizes around "just in case". But the 3/8" and 3/4" that I use a lot have long been replaced with better ones that hold up longer.

Jason wrote:
(snipping lots of priors)
I wrote:
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Um... Heh.. I made a booboo blunder. :)
Was working on something else this morning and had reason to drill a few holes. Chucked a bit in the dewalt and commenced drilling... and realized it was drilling quite well - and fast.
Turns out I had somehow changed the top speed switch from "1" to "2" and didn't notice. Hmm, I wonder. Fetched the aforementioned forstner bit, chucked it up, grabbed my scrap piece, and set the switch to "1".
Guess what? More speed control, and I was able to drill in quite well and with only a little effort I was halfway through the scrap. More importantly - no skating!
Morale of the story: user error on my part. So for precision holes freehand, I'll use a forstner in the drill (spade bits otherwise), but still prefer the drill press for 'em.
Jason Buckler (typing with horked thumb in splint is fun!) Marietta, GA

I may be over-simplifying but I think the center point is there to provide a small reference pilot for true center if you need to extend a smaller diameter bit through for a bolt or dowel; at least that is what I have used it for over the last 40 years or so.
As a kid and while going to colege, I worked in a production shop that did a lot of turnings, they used forster bits to set up the ends of the stock for the tail piece.
I have always planned machining operations around that when working with wood. Not so often but also with plastics.
I think that a couple of the operations even used modified bits to trip the top of legs outer diameter to uniform sizes so they would fit into the corresponding hole that was bored to receive it.
BTW - new here since Verizon took away alt binaries pictures woodworking
Thanks for having me
Jay
wrote:
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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

John Martin wrote:
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Yes, exactly right on both counts. I ment carbide, and yes, my problem was keeping the bit from skating around.
As I said originally, I stopped after a minute. However, once I got past the 1/8th inch mark I had enough of a "go" to where I could have continued on, since the bit was sharp enough. I didn't though, since I was already "job done" on the drill press.
Jason Buckler Marietta, GA

I bought some High Speed Steel wood bits from an online vendor of some repute (the name of which escapes me) and was impressed when removing the plastic coating each tip had been dipped in as I sliced my finger on the bit as I removed the coating.
They worked wonders in the wood, too!
I bought HFT "Forstner" bits and another set from one of those mobile vendor "Tool Sales" and one from Bosch (at Lowes). The Bosch was more expensive (35mm?) than was the first set of six from HFT and the larger set (to 2.5") from the mobile vendor.
I use a drill press - mostly, But I have used them in "electric drills" from time to time with decent results - certainly nothing to complain about.
Having said that, I wonder if anyone has any experience with a HSS set from Hartville Tools, or another vendor as I would love to buy a set as sharp as the bits first referenced, above, in the Forstner style.
PS, the Irwin Auger Bits with Three (3) flutes are a joy to use. In my 14.4VDC Sears drill *shorter than my 19.2VDC model, with less torque/ power" I was easily able to "punch" holes through the floor joits to run my wiring "out of the way." They have that screw starter point and pull themselves through leaving a nice clean hole, If you hit a nail enroute, however, they suffer significantly!