Dd

"DGDevin"

27/02/2009 11:40 AM

Forstner bit recommendations

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?


This topic has 14 replies

TD

Toe Dipper

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 12:15 PM

On Feb 27, 2:40=A0pm, "DGDevin" <[email protected]> wrote:
> I have a project requiring a dozen 2" holes through a piece of 2" laminat=
ed
> pine--actually two pieces of 1" laminated pine but drilling them together
> seemed like a good way to ensure the holes would line up. =A0Not having a
> Forstner bit that large I bought a Woodcraft house-brand bit for ten buck=
s
> and fired up the drill press. =A0I got maybe half a dozen clean, easy hol=
es.
> 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. =A0But how much better, where=
is
> the point of diminishing returns? =A0Would moving up to a $20 CMT be a re=
al
> improvement or is a bit in that price range likely to be from the same
> source as the house-brand bit? =A0Is 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? =A0What's=
the
> magic price range at which performance goes way up but doesn't irritate
> SWMBO beyond the redline?

I bought this Porter Cable set at Home Depot and have been pleased so
far.
http://www.amazon.com/Porter-PCFSB12-2-Inch-Forstner-Assortment/dp/B000HCZ4=
FM
http://www.drillspot.com/products/373652/Porter_Cable_PCFSB12_Forstner_Dril=
l_Bit_Set

IIRC it was ~$40 at Home Depot.

Dd

"DGDevin"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 5:40 PM

Gerald Ross wrote:

> 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.

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

MH

"Martin H. Eastburn"

in reply to "DGDevin" on 27/02/2009 11:40 AM

28/02/2009 8:47 PM

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.

Martin

DGDevin wrote:
> Hoosierpopi wrote:
>
>> They have a comparison chart at
>> http://www.taunton.com/finewoodworking/FWNPDFfree/99930380-forstner-bit-online-extra.pdf
>> 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.
>
>> 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!
>
> 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.
>
>

Sk

"Swingman"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 2:20 PM

"DGDevin" wrote

> 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

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

--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)



Dd

"DGDevin"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 1:40 PM

Leon wrote:

> 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 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.

Hg

Hoosierpopi

in reply to "DGDevin" on 27/02/2009 11:40 AM

28/02/2009 6:23 AM

On Feb 27, 1:40=A0pm, "DGDevin" <[email protected]> wrote:
> I have a project requiring a dozen 2" holes through a piece of 2" laminat=
ed

http://www.leevalley.com/wood/page.aspx?c=3D2&p=3D42247&cat=3D1,180,42240

The 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
http://www.taunton.com/finewoodworking/FWNPDFfree/99930380-forstner-bit-onl=
ine-extra.pdf
that 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"
http://www.leevalley.com/wood/page.aspx?c=3D2&p=3D42245&cat=3D1,180,42240,4=
5533,42240

I 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.




Sb

"SonomaProducts.com"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 1:48 PM

I would use an adjustable circle cutter for Pine. For instance

http://www.mikestools.com/825-6510-Wheel-Circle-Cutter.aspx

On Feb 27, 11:40=A0am, "DGDevin" <[email protected]> wrote:
> I have a project requiring a dozen 2" holes through a piece of 2" laminat=
ed
> pine--actually two pieces of 1" laminated pine but drilling them together
> seemed like a good way to ensure the holes would line up. =A0Not having a
> Forstner bit that large I bought a Woodcraft house-brand bit for ten buck=
s
> and fired up the drill press. =A0I got maybe half a dozen clean, easy hol=
es.
> 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. =A0But how much better, where=
is
> the point of diminishing returns? =A0Would moving up to a $20 CMT be a re=
al
> improvement or is a bit in that price range likely to be from the same
> source as the house-brand bit? =A0Is 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? =A0What's=
the
> magic price range at which performance goes way up but doesn't irritate
> SWMBO beyond the redline?

Dd

"DGDevin"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 5:39 PM

[email protected] wrote:

> 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 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....

b

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 4:52 PM

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.

Dd

"DGDevin"

in reply to "DGDevin" on 27/02/2009 11:40 AM

28/02/2009 9:20 AM

Hoosierpopi wrote:

> They have a comparison chart at
> http://www.taunton.com/finewoodworking/FWNPDFfree/99930380-forstner-bit-online-extra.pdf
> 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.

> 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!

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.

GR

Gerald Ross

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 7:12 PM

DGDevin wrote:
> 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?
>
>
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.

--
Gerald Ross
Cochran, GA

Laugh, and the world ignores you.
Crying doesn't help either.



Dd

"DGDevin"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 1:43 PM

Norm Dresner wrote:

> 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

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....

Lr

"Leon"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 3:21 PM


"DGDevin" <[email protected]> wrote in message
news:[email protected]...
>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?
>

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.

ND

"Norm Dresner"

in reply to "DGDevin" on 27/02/2009 11:40 AM

27/02/2009 8:46 PM

"DGDevin" <[email protected]> wrote in message
news:[email protected]...
|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?
|

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


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