Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

"N_Cook" wrote in message
...
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks.
Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the
shank-end
of a flute, or different spark colour perhaps ?



If you have some known steel bits of similar size, the carbide ones are a
great deal heavier. Also, they are darker gray.

Aluminum oxide might "skitter," but silicon carbide disks will dig in. I
don't think they'll spark at all.

--
Ed Huntress

On Jun 22, 11:27*am, "N_Cook" wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

My 1st suggestion would be to check them with a magnet. I don't think
carbide is magnetic

CarlBoyd

"Carl" wrote in message
...
On Jun 22, 11:27 am, "N_Cook" wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks.
Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the
shank-end
of a flute, or different spark colour perhaps ?

My 1st suggestion would be to check them with a magnet. I don't think
carbide is magnetic

CarlBoyd

Tungsten carbide itself is not, but the binder usually is. Carbide binders
usually consist of cobalt and/or nickel, both of which are ferromagnetic.

If you have a steel bit to compare it with (or a steel drill bit of
comparable size), you'll notice that the attraction of the carbide to a
magnet is much weaker than that of steel. But it can be hard to tell if you
don't have a steel piece with which to compare it.

--
Ed Huntress

On 2010-06-22, N_Cook wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

Use a known piece of HSS, like a lathe bit, and try scratching it with
the cutter in question. carbide will scratch HSS easily.

For bigger sizes, I just tell by weight.

i

On 2010-06-22, N_Cook wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

It would not grind well at all -- unless you had a diamond
wheel.

If these are the kind with a color collar to mark the size just
before the transition from the 1/8" shank to the bit, it is likely that
this is for printed circuit board drilling -- and carbide is the only
choice under those conditions. I used a HSS #70 bit once to drill about
50 holes in a G-10 (Glass-epoxy) PCB for mounting components and by the
time I was done, the shape of the bit was closer to that of a needle,
and the holes were lined with glass fibers. The heat had burned out the
epoxy, leaving the fibers.

It was then that I put in an order for solid carbide bits, and
neve regretted it.

I've picked up batches of the PCB drills at hamfests with the
color colars. IIRC, the color indicates the last digit of the size, but
I've never been truly sure.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 2010-06-22, Ed Huntress wrote:

"N_Cook" wrote in message
...
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks.
Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the
shank-end
of a flute, or different spark colour perhaps ?



If you have some known steel bits of similar size, the carbide ones are a
great deal heavier. Also, they are darker gray.

I was thinking of mentioning the weight/mass (juggling it in one
hand), which I user as a quick guide in larger tools -- but these are
1/8" shanks and much smaller actual cutting parts -- not enough to
really give a good feel for the mass -- especially lacking known HSS
versions in the same format.

Aluminum oxide might "skitter," but silicon carbide disks will dig in. I
don't think they'll spark at all.

I think that you are right. It has been a long time since I
tried to sharpen carbide on a standard stone. :-)

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Now Don - I know what G-10 is - but isn't it FR-4 ?

I think G-10 was banned or stopped being used due to flame issues.
You can usually find good carbide drills for pcb drilling in the kits
for Dremel machines. They normally have a plastic ring on them with the
size or spec.

I used to route and drill pcb material on a small CNC prototype machine
and drills of all types and spot as well as hole. Milling with 5 mill
two flute, flush cutting endmills.

Still have some of the software (impedance calculations) and material selection.

Wonder if any of my former pcb vendors are still working.
I was doing work with sample designs of CMOS and SiGe.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 6/22/2010 9:04 PM, DoN. Nichols wrote:
On 2010-06-22, wrote:
Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

It would not grind well at all -- unless you had a diamond
wheel.

If these are the kind with a color collar to mark the size just
before the transition from the 1/8" shank to the bit, it is likely that
this is for printed circuit board drilling -- and carbide is the only
choice under those conditions. I used a HSS #70 bit once to drill about
50 holes in a G-10 (Glass-epoxy) PCB for mounting components and by the
time I was done, the shape of the bit was closer to that of a needle,
and the holes were lined with glass fibers. The heat had burned out the
epoxy, leaving the fibers.

It was then that I put in an order for solid carbide bits, and
neve regretted it.

I've picked up batches of the PCB drills at hamfests with the
color colars. IIRC, the color indicates the last digit of the size, but
I've never been truly sure.

Enjoy,
DoN.

On Tue, 22 Jun 2010 23:15:08 -0500, "Martin H. Eastburn"
wrote:

Now Don - I know what G-10 is - but isn't it FR-4 ?

I think G-10 was banned or stopped being used due to flame issues.
You can usually find good carbide drills for pcb drilling in the kits
for Dremel machines. They normally have a plastic ring on them with the
size or spec.

I used to route and drill pcb material on a small CNC prototype machine
and drills of all types and spot as well as hole. Milling with 5 mill
two flute, flush cutting endmills.

Still have some of the software (impedance calculations) and material selection.

Wonder if any of my former pcb vendors are still working.
I was doing work with sample designs of CMOS and SiGe.

Martin


I have several thousand of these drills, if anyone needs any sets

Gunner

One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch

Thanks all. AFAIAA the tips of masonry drill bits are always carbide. Tried
an unused part of a needle file against such a piece of carbide and a known
HSS drill bit and could not convince myself either way. Don't know what sort
of grit, but rust brown (binder?) parting off disc in a Dremmel. Just
cleaned up the surface of the carbide and slotted the HSS.
So repeating with these unknown small bits , HSS

On 2010-06-23, Gunner Asch wrote:
On Tue, 22 Jun 2010 23:15:08 -0500, "Martin H. Eastburn"
wrote:

Now Don - I know what G-10 is - but isn't it FR-4 ?

Not when I was doing it. :-)

I think G-10 was banned or stopped being used due to flame issues.

Do you know when?

You can usually find good carbide drills for pcb drilling in the kits
for Dremel machines. They normally have a plastic ring on them with the
size or spec.

And in batches at hamfests -- for whatever reason. I suspect
that they are "resharps" which are close to their minimum length. Sold
in large lots by the houses which use them -- or perhaps the
resharpening house.

I used to route and drill pcb material on a small CNC prototype machine
and drills of all types and spot as well as hole. Milling with 5 mill
two flute, flush cutting endmills.

Nice!

Still have some of the software (impedance calculations) and material selection.

Runs on what OS and hardware?

Wonder if any of my former pcb vendors are still working.
I was doing work with sample designs of CMOS and SiGe.

Martin


I have several thousand of these drills, if anyone needs any sets

Define "set" here. What range of sizes, in what step size? I
would presume a max size of 1/8", and a minimum down where the skinny
leads on diodes and TO-5 can transistors lived -- perhaps plus a bit to
allow for through hole plating.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Remember the carbide is C-2 on a lot of stuff up to c-4. C-6 is on the machines.

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 6/23/2010 4:31 AM, N_Cook wrote:
Thanks all. AFAIAA the tips of masonry drill bits are always carbide. Tried
an unused part of a needle file against such a piece of carbide and a known
HSS drill bit and could not convince myself either way. Don't know what sort
of grit, but rust brown (binder?) parting off disc in a Dremmel. Just
cleaned up the surface of the carbide and slotted the HSS.
So repeating with these unknown small bits , HSS

Not exactly. I suspect it was during Viet Nam or NASA.

I believe it was in the 70's. By the early 80's I kept hearing FR-4.
http://en.wikipedia.org/wiki/FR-4 I suspect the NEMA spec could be checked.

Looks like G10 is still in use! - catches on fire it keeps burning.
FR4 self extinguishes.

Interesting. I know when dealing with PCB's that were in the tens of thousands
in parts on a table - you don't use risky material.

I suspect - Mil banned them - e.g. NASA and Aircraft for certain.

Martin


Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 6/23/2010 7:08 PM, DoN. Nichols wrote:
On 2010-06-23, Gunner wrote:
On Tue, 22 Jun 2010 23:15:08 -0500, "Martin H. Eastburn"
wrote:

Now Don - I know what G-10 is - but isn't it FR-4 ?

Not when I was doing it. :-)

I think G-10 was banned or stopped being used due to flame issues.

Do you know when?

You can usually find good carbide drills for pcb drilling in the kits
for Dremel machines. They normally have a plastic ring on them with the
size or spec.

And in batches at hamfests -- for whatever reason. I suspect
that they are "resharps" which are close to their minimum length. Sold
in large lots by the houses which use them -- or perhaps the
resharpening house.

I used to route and drill pcb material on a small CNC prototype machine
and drills of all types and spot as well as hole. Milling with 5 mill
two flute, flush cutting endmills.

Nice!

Still have some of the software (impedance calculations) and material selection.

Runs on what OS and hardware?

Wonder if any of my former pcb vendors are still working.
I was doing work with sample designs of CMOS and SiGe.

Martin


I have several thousand of these drills, if anyone needs any sets

Define "set" here. What range of sizes, in what step size? I
would presume a max size of 1/8", and a minimum down where the skinny
leads on diodes and TO-5 can transistors lived -- perhaps plus a bit to
allow for through hole plating.

Enjoy,
DoN.

On Tue, 22 Jun 2010 16:27:06 +0100, "N_Cook"
wrote:

Needless to say no original packing. Sub-mm bits with 1/8 inch shanks. Other
than by breaking easily, using hand drill rather than pedestal. Would
carbide just make a small grinding disc skitter trying against the shank-end
of a flute, or different spark colour perhaps ?

My standard test for sub-mm bits with 1/8" shanks is to look at them
crosseyed. If they snap, they're carbide.

They work OK in a small precision drillpress at high speed, as for
drilling circuit boards.

On 24 Jun 2010 00:08:50 GMT, "DoN. Nichols"
wrote:
Define "set" here. What range of sizes, in what step size? I
would presume a max size of 1/8", and a minimum down where the skinny
leads on diodes and TO-5 can transistors lived -- perhaps plus a bit to
allow for through hole plating.

Enjoy,
DoN.

The low-cost PCB houses have min hole sizes around 12 to 14 mils now,
as for vias on surfacemount boards.

On 24 Jun 2010 00:08:50 GMT, "DoN. Nichols"
wrote:


I have several thousand of these drills, if anyone needs any sets

Define "set" here. What range of sizes, in what step size? I
would presume a max size of 1/8", and a minimum down where the skinny
leads on diodes and TO-5 can transistors lived -- perhaps plus a bit to
allow for through hole plating.

Enjoy,
DoN.

Ill dig em out and run sorta an inventory.

Gunner

One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch

On 2010-06-26, Gunner Asch wrote:
On 24 Jun 2010 00:08:50 GMT, "DoN. Nichols"
wrote:


I have several thousand of these drills, if anyone needs any sets

Define "set" here. What range of sizes, in what step size? I
would presume a max size of 1/8", and a minimum down where the skinny
leads on diodes and TO-5 can transistors lived -- perhaps plus a bit to
allow for through hole plating.

Ill dig em out and run sorta an inventory.

Thanks!

BTW -- did you check out the 6-jaw chuck jaws you have, and find
whether any of them would be likely to fit my Burnard-Pratt 6-jaw --
especially outside jaws?

Again, thanks,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---