About carbide drill bits

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Pimpom

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Mar 12, 2012, 4:17:31 AM3/12/12
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Carbide drill bits of 0.7-1.2mm size are priced at ~US$10 each at
Digikey and Farnell while they are offered for a fraction of that
at ebay.com, typically ~$1-1.50 per piece in a set. Does anyone
know what these cheaper offerings from eBay are like for drilling
FR4 boards?


Chieftain of the Carpet Crawlers

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Mar 12, 2012, 4:42:35 AM3/12/12
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On Mon, 12 Mar 2012 13:47:31 +0530, "Pimpom" <Pim...@invalid.invalid>
wrote:
Are you sure the digikey stuff isn't for a ten pack?

That is the way we bought drills years ago. Files too.

spamtrap1888

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Mar 12, 2012, 4:48:52 AM3/12/12
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On Mar 12, 1:42 am, Chieftain of the Carpet Crawlers
Digikey carries Injectorall bits, which come one to a package for
carbide; ten to a package for HSS:

http://www.injectorall.com/drillbits.htm

Spehro Pefhany

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Mar 12, 2012, 7:41:45 AM3/12/12
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Don't know, but I've had spotty results (used to be uniformly dismal)
with Chinese cutting tools.

Digikey isn't really the best place to buy that sort of thing- KBC has
M.A. Ford (made in USA) carbide 1/8" shank drills for $4.10 ea., which
is not bad for a few pieces. McMaster wants about $4.50 each, but I
don't think they ship to India.

This guy claims to have Kyocera bits at a very reasonable price
(havn't tried him)

http://www.routerburr.com/servlet/the-DRILLS/Categories


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

John Larkin

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Mar 12, 2012, 10:16:19 AM3/12/12
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On Mon, 12 Mar 2012 13:47:31 +0530, "Pimpom" <Pim...@invalid.invalid>
wrote:
Without a serious Excelon type drill (zillion RPM air bearings, feed
rate control, entry media) carbides tend to break. For home-drilled
boards, use cheap steel drills and toss them when they get dull.


--

John Larkin, President Highland Technology Inc
www.highlandtechnology.com jlarkin at highlandtechnology dot com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom timing and laser controllers
Photonics and fiberoptic TTL data links
VME analog, thermocouple, LVDT, synchro, tachometer
Multichannel arbitrary waveform generators

Nico Coesel

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Mar 12, 2012, 11:00:20 AM3/12/12
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John Larkin <jjla...@highNOTlandTHIStechnologyPART.com> wrote:

>On Mon, 12 Mar 2012 13:47:31 +0530, "Pimpom" <Pim...@invalid.invalid>
>wrote:
>
>>Carbide drill bits of 0.7-1.2mm size are priced at ~US$10 each at
>>Digikey and Farnell while they are offered for a fraction of that
>>at ebay.com, typically ~$1-1.50 per piece in a set. Does anyone
>>know what these cheaper offerings from eBay are like for drilling
>>FR4 boards?
>>
>
>Without a serious Excelon type drill (zillion RPM air bearings, feed
>rate control, entry media) carbides tend to break. For home-drilled
>boards, use cheap steel drills and toss them when they get dull.

Bad idea. An HSS drill is dull after about 10 holes of FR4. Even for
hobby purposes you need carbide drill for FR4. I never had problems
with carbide drills breaking unless I drilled in the aluminum base of
my drill-press.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
--------------------------------------------------------------

John Larkin

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Mar 12, 2012, 11:21:24 AM3/12/12
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On Mon, 12 Mar 2012 15:00:20 GMT, ni...@puntnl.niks (Nico Coesel)
wrote:

>John Larkin <jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>
>>On Mon, 12 Mar 2012 13:47:31 +0530, "Pimpom" <Pim...@invalid.invalid>
>>wrote:
>>
>>>Carbide drill bits of 0.7-1.2mm size are priced at ~US$10 each at
>>>Digikey and Farnell while they are offered for a fraction of that
>>>at ebay.com, typically ~$1-1.50 per piece in a set. Does anyone
>>>know what these cheaper offerings from eBay are like for drilling
>>>FR4 boards?
>>>
>>
>>Without a serious Excelon type drill (zillion RPM air bearings, feed
>>rate control, entry media) carbides tend to break. For home-drilled
>>boards, use cheap steel drills and toss them when they get dull.
>
>Bad idea.

Works for me.

dagmarg...@yahoo.com

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Mar 12, 2012, 2:12:09 PM3/12/12
to
On Mar 12, 10:00 am, n...@puntnl.niks (Nico Coesel) wrote:
> John Larkin <jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
> >On Mon, 12 Mar 2012 13:47:31 +0530, "Pimpom" <Pim...@invalid.invalid>
> >wrote:
>
> >>Carbide drill bits of 0.7-1.2mm size are priced at ~US$10 each at
> >>Digikey and Farnell while they are offered for a fraction of that
> >>at ebay.com, typically ~$1-1.50 per piece in a set. Does anyone
> >>know what these cheaper offerings from eBay are like for drilling
> >>FR4 boards?
>
> >Without a serious Excelon type drill (zillion RPM air bearings, feed
> >rate control, entry media) carbides tend to break. For home-drilled
> >boards, use cheap steel drills and toss them when they get dull.
>
> Bad idea. An HSS drill is dull after about 10 holes of FR4. Even for
> hobby purposes you need carbide drill for FR4. I never had problems
> with carbide drills breaking unless I drilled in the aluminum base of
> my drill-press.

The secret for carbide is a drill setup with minimum run-out, no give,
and no wobble.

I have an old-style Dremel drill stand that holds the tool steady, and
lifts the
table up and down, like a "knee mill." That works well.

The later Dremel drill stands move the tool up and down to drill
holes. The Dremel shifts slightly
as you lower it into the workpiece, snapping the bit.

Dremels aren't perfect, but if the bearings are reasonably tight
they'll get the job done.


--
Cheers,
James Arthur

Spehro Pefhany

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Mar 12, 2012, 3:46:58 PM3/12/12
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On Mon, 12 Mar 2012 11:12:09 -0700 (PDT), dagmarg...@yahoo.com
wrote:
I've had few to no problems*. You want to run them as fast spindle
speed as possible. They cut FR4 like butta. I don't often drill much
less than 0.8mm (0.031"), which is pretty sturdy- if you're trying to
drill 0.015" holes, things might be dicier.

* A few weeks ago I reached into one of the ubiquitous little boxes of
resharpened carbide bits by mistake and about 8mm of tiny via-size bit
punctured my finger and broke off in the finger. Ouch. This was after
breaking a 1/4-20 tap off in a part, so I was grumpy to start with
(took a couple hours to salvage the part). I thought a cheap "set of
taps" would be okay at that huge size- I was wrong- bought some good
quality ones (Chinese, but top-notch stuff) and no more problems. The
cheap-a** 4-40 die wouldn't even thread onto a proper sized brass
turning. Criminally bad "tool shaped" garbage- ultra brittle, dull,
and not the right dimensions.

Moral.. don't go cheap on cutting tools!

Pimpom

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Mar 12, 2012, 4:05:17 PM3/12/12
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"Spehro Pefhany" <spef...@interlogDOTyou.knowwhat> wrote in
message news:panrl7tkas0k67fhr...@4ax.com...
> On Mon, 12 Mar 2012 13:47:31 +0530, the renowned "Pimpom"
> <Pim...@invalid.invalid> wrote:
>
>>Carbide drill bits of 0.7-1.2mm size are priced at ~US$10 each
>>at
>>Digikey and Farnell while they are offered for a fraction of
>>that
>>at ebay.com, typically ~$1-1.50 per piece in a set. Does anyone
>>know what these cheaper offerings from eBay are like for
>>drilling
>>FR4 boards?
>>
>
> Don't know, but I've had spotty results (used to be uniformly
> dismal)
> with Chinese cutting tools.

Hmm... I suspect that some or most of those cheap bits at ebay
are Chinese products.

>
> Digikey isn't really the best place to buy that sort of thing-
> KBC has
> M.A. Ford (made in USA) carbide 1/8" shank drills for $4.10
> ea., which
> is not bad for a few pieces. McMaster wants about $4.50 each,
> but I
> don't think they ship to India.

It wouldn't make much difference for me even if they did ship to
India because import hassles are a real PITA and well nigh
insurmountable for those of us in remote parts of the country.
But things have started looking up a bit recently in that
respect. There are now at least a couple of Indian companies who
offer to import just about anything from the US for a client.
Their minimum shipping charge is for 1lb.

>
> This guy claims to have Kyocera bits at a very reasonable price
> (havn't tried him)
>
> http://www.routerburr.com/servlet/the-DRILLS/Categories

The prices are comparable to those at ebay and are certainly
better than at those other sources. At least the manufacturer's
name is known. Do you know anything about the other brand
mentioned there - Precision Carbide? Unless someone comes along
with a more attractive suggestion - not necessarily a lower
price - I think I'll make a trial order for a ten-pack each of 2
or 3 different sizes.

Another thing I'll have to deal with is the drill. The 10k rpm
drill I now use came only with 0.8mm, 1mm and 2.3mm collets.
Thanks for the helpful input.


Baron

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Mar 12, 2012, 4:12:24 PM3/12/12
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Pimpom Inscribed thus:
All the cheap ones I've bought have been sharpened off centre.

--
Best Regards:
Baron.

Spehro Pefhany

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Mar 12, 2012, 4:34:52 PM3/12/12
to
On Tue, 13 Mar 2012 01:35:17 +0530, "Pimpom" <Pim...@invalid.invalid>
wrote:
>
>It wouldn't make much difference for me even if they did ship to
>India because import hassles are a real PITA and well nigh
>insurmountable for those of us in remote parts of the country.
>But things have started looking up a bit recently in that
>respect. There are now at least a couple of Indian companies who
>offer to import just about anything from the US for a client.
>Their minimum shipping charge is for 1lb.

McMaster will permanently cut them off if they know it's being
exported. They really want to add to the US trade deficit- only
existing large export customers are being supported.

>Another thing I'll have to deal with is the drill. The 10k rpm
>drill I now use came only with 0.8mm, 1mm and 2.3mm collets.
>Thanks for the helpful input.

AFAIK, everyone uses 1/8" (3.175mm) shank drills (same as a Dremel
tool), so if you get one of those you'll be okay for just about
anything. It helps to be able to change the bits quickly when all the
shanks are identical. With collars you can get the length spot on too.

Nico Coesel

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Mar 12, 2012, 5:17:41 PM3/12/12
to
The thinnest drill I have 0.6mm. No problems using it. I use the
ancestor of this drill-press:
http://www.nutmegwoodworking.ca/products/proxxon/28606-web.jpg

I've drilled thousands of holes with it using carbide drills.

dagmarg...@yahoo.com

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Mar 12, 2012, 9:24:36 PM3/12/12
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On Mar 12, 4:17 pm, n...@puntnl.niks (Nico Coesel) wrote:
> Spehro Pefhany <speffS...@interlogDOTyou.knowwhat> wrote:
> >On Mon, 12 Mar 2012 11:12:09 -0700 (PDT), dagmargoodb...@yahoo.com
> >wrote:
>

> >>I have an old-style Dremel drill stand that holds the tool steady, and
> >>lifts the
> >>table up and down, like a "knee mill."  That works well.
>
> >>The later Dremel drill stands move the tool up and down to drill
> >>holes.  The Dremel shifts slightly
> >>as you lower it into the workpiece, snapping the bit.
>
> >>Dremels aren't perfect, but if the bearings are reasonably tight
> >>they'll get the job done.
>
> >I've had few to no problems*. You want to run them as fast spindle
> >speed as possible. They cut FR4 like butta. I don't often drill much
> >less than 0.8mm (0.031"), which is pretty sturdy- if you're trying to
> >drill 0.015" holes, things might be dicier.
>
> The thinnest drill I have 0.6mm. No problems using it. I use the
> ancestor of this drill-press:http://www.nutmegwoodworking.ca/products/proxxon/28606-web.jpg
>
> I've drilled thousands of holes with it using carbide drills.


Proxxon--those are said to be very fine machines.

Here's my preferred Dremel drill press:
http://www.ebay.com/itm/Dremel-Drill-Press-210-/330700307907?pt=LH_DefaultDomain_0&hash=item4cff463dc3

The knob just below the table raises and lowers the table; the Dremel
doesn't move.

A cool mechanism keeps it stable: the table is supported underneath by
a post, centered under the drill bit. Turning the knob operates a
cam, which raises and lowers the table. The table twists a little,
but because the center of twist is exactly the same as the drilling
point, it doesn't matter.

This model #210 doesn't fit newer Dremel tools--I had to buy an older
tool to use it.

Dremel's new drill-press accessory snaps carbide bits instantly.

--
Cheers,
James Arthur

dagmarg...@yahoo.com

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Mar 12, 2012, 9:41:42 PM3/12/12
to
On Mar 12, 2:46 pm, Spehro Pefhany <speffS...@interlogDOTyou.knowwhat>
wrote:
> On Mon, 12 Mar 2012 11:12:09 -0700 (PDT), dagmargoodb...@yahoo.com
Yes, I've used the smaller sizes. Because the new-style drill press
didn't work I used to run 0.012 bits by hand(*)--that's a pain.
Nowdays I think I'd try the old Model 210.

(*) index finger pressing on top for a bearing, rotate with 2nd finger
+ thumb. I managed 2 to 4 holes per bit before breaking them. :-)

> * A few weeks ago I reached into one of the ubiquitous little boxes of
> resharpened carbide bits by mistake and about 8mm of tiny via-size bit
> punctured my finger and broke off in the finger. Ouch. This was after
> breaking a 1/4-20 tap off in a part, so I was grumpy to start with
> (took a couple hours to salvage the part). I thought a cheap "set of
> taps" would be okay at that huge size- I was wrong- bought some good
> quality ones (Chinese, but top-notch stuff) and no more problems. The
> cheap-a** 4-40 die wouldn't even thread onto a proper sized brass
> turning. Criminally bad "tool shaped" garbage- ultra brittle, dull,
> and not the right dimensions.

Disgusting. Good clean, sharp, quality tools are a joy. HSS--
maintaining full hardness at red heat--is amazing.

I snapped a carbide bit off in a workpiece a couple days ago--that's a
pain. It was a larger diameter bit so I thought using the big drill
press would be okay. It wasn''t.

> Moral.. don't go cheap on cutting tools!

Rodger that.

--
Cheers,
James Arthur

Glenn Gundlach

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Mar 13, 2012, 12:06:23 AM3/13/12
to
On Mar 12, 6:24 pm, dagmargoodb...@yahoo.com wrote:
> On Mar 12, 4:17 pm, n...@puntnl.niks (Nico Coesel) wrote:
>
>
>
>
>
> > Spehro Pefhany <speffS...@interlogDOTyou.knowwhat> wrote:
> > >On Mon, 12 Mar 2012 11:12:09 -0700 (PDT), dagmargoodb...@yahoo.com
> > >wrote:
>
> > >>I have an old-style Dremel drill stand that holds the tool steady, and
> > >>lifts the
> > >>table up and down, like a "knee mill."  That works well.
>
> > >>The later Dremel drill stands move the tool up and down to drill
> > >>holes.  The Dremel shifts slightly
> > >>as you lower it into the workpiece, snapping the bit.
>
> > >>Dremels aren't perfect, but if the bearings are reasonably tight
> > >>they'll get the job done.
>
> > >I've had few to no problems*. You want to run them as fast spindle
> > >speed as possible. They cut FR4 like butta. I don't often drill much
> > >less than 0.8mm (0.031"), which is pretty sturdy- if you're trying to
> > >drill 0.015" holes, things might be dicier.
>
> > The thinnest drill I have 0.6mm. No problems using it. I use the
> > ancestor of this drill-press:http://www.nutmegwoodworking.ca/products/proxxon/28606-web.jpg
>
> > I've drilled thousands of holes with it using carbide drills.
>
> Proxxon--those are said to be very fine machines.
>
> Here's my preferred Dremel drill press:http://www.ebay.com/itm/Dremel-Drill-Press-210-/330700307907?pt=LH_De...
>
> The knob just below the table raises and lowers the table; the Dremel
> doesn't move.
>
> A cool mechanism keeps it stable: the table is supported underneath by
> a post, centered under the drill bit.  Turning the knob operates a
> cam, which raises and lowers the table.  The table twists a little,
> but because the center of twist is exactly the same as the drilling
> point, it doesn't matter.
>
> This model #210 doesn't fit newer Dremel tools--I had to buy an older
> tool to use it.
>
> Dremel's new drill-press accessory snaps carbide bits instantly.
>
> --
> Cheers,
> James Arthur

I have the same except I drilled a 1/8" hole in the center of the
table so using 0.035" carbide bits don't hit any of the aluminum -
though I haven't drilled FR-4 in quite a while. The board houses are
so cheap it isn't really worth doing at home.


ehsjr

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Mar 13, 2012, 11:08:07 PM3/13/12
to
Get used dental burs from your dentist, or buy them new if
you can find them for a reasonable price. They work well
in my (newer style) Dremel drill press - haven't broken one
yet.

Ed

TheQuickBrownFox

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Mar 13, 2012, 11:13:07 PM3/13/12
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On Tue, 13 Mar 2012 23:08:07 -0400, ehsjr <eh...@nospamverizon.net>
wrote:
Filch the dumpster at the urgent care too! Get that stainless!

They used to autoclave everything and that was enough... before AIDS.

whit3rd

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Mar 17, 2012, 3:55:46 AM3/17/12
to
At a guess, they were just fine, when they were new.
Carbide drills for circuit board manufacture are mainly not
resharpened, but are discarded (sold as surplus) after
a certain number of holes have been drilled. If you aren't doing
plated-through holes, they're certainly good enough at
end-of-life for another few thousand holes.

Rick

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Mar 17, 2012, 8:18:12 AM3/17/12
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"whit3rd" <whi...@gmail.com> wrote in message
news:31266004.2000.1331970946877.JavaMail.geo-discussion-forums@ynbo9...
I usually buy two or three to get a rather good assortment.
http://www.harborfreight.com/20-piece-solid-carbide-micro-bit-grab-bag-44924.html


dagmarg...@yahoo.com

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Mar 17, 2012, 9:53:42 AM3/17/12
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> I have the same except I drilled a 1/8" hole in the center of the
> table so using 0.035" carbide bits don't hit any of the aluminum -
> though I haven't drilled FR-4 in quite a while. The board houses are
> so cheap it isn't really worth doing at home.
>
> G²

My (preferred) model 210 has a formica-looking table.

Poking around I read the latest Dremel drill press
accessories are better. The "new" bit-snapper I spoke of
is the Model 212
http://www.biscotoolsupply.com/shop/images/dremel_attachment_copy.jpg

but it seems they've replaced it with the Work Station 220-01.
http://www.shop.com/DREMEL_Drill_Press-437339250-484496251-p+.xhtml?sourceid=1414

The z-axis, sloppy on the #210, appears re-done.

Might be worth a look next time I'm shopping...

--
Cheers,
James Arthur
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