Dave Hinz wrote:
On Wed, 16 Jan 2008 23:50:10 +0000, Christopher Tidy wrote:


That sounds cool. How do you make a tap in the home shop?


I may be doing it the wrong and/or hard way but, I've done it a couple
of times. Once when I had a die of the right size but not a tap - used
it to thread some rod, then just ground out some relief cuts on the rod
to make a tap-shaped object. Very freehand and very much not optimal
angles for anything but, it made the cut I needed for exactly one hole.
Second one was a bit more ambitious, single-pointed a threaded rod on
the lathe and again hand-cut 2 relief cuts. Made the hole I needed.
Probably not the right way but, for this job, was fine. (metric
left-hand thread for one-time use, don't ask).

Did you have to heat treat or case harden it? Or were you only tapping
brass?

Best wishes,

Chris

On Thu, 17 Jan 2008 02:28:08 +0000, Christopher Tidy wrote:
Dave Hinz wrote:

I may be doing it the wrong and/or hard way but, I've done it a couple
of times.
(snip)

Did you have to heat treat or case harden it? Or were you only tapping
brass?

Once aluminum, once mystery-steel for a nut that was expected to have
about 3 uses ever. Lots of lube and it came out OK but I wouldn't
suggest it for a "real" project. This was for a water-pump tool for
Triumph/Saab inline-4 engines, and several hand-turned uses per year are
to be expected, kind of a gear puller with a threaded end rather than a
point. If it was anything that'd deal with any number of cuts, I
probably would have just bought the oddball tap. But for a one-off of
not-rocket-science dirty hack spec, it was good enough. (I never
claimed to be a machinist, I'm just a guy with machine tools in the
basement).

Dave Hinz wrote:
On Thu, 17 Jan 2008 02:28:08 +0000, Christopher Tidy wrote:

Dave Hinz wrote:

I may be doing it the wrong and/or hard way but, I've done it a couple
of times.

(snip)


Did you have to heat treat or case harden it? Or were you only tapping
brass?


Once aluminum, once mystery-steel for a nut that was expected to have
about 3 uses ever. Lots of lube and it came out OK but I wouldn't
suggest it for a "real" project. This was for a water-pump tool for
Triumph/Saab inline-4 engines, and several hand-turned uses per year are
to be expected, kind of a gear puller with a threaded end rather than a
point. If it was anything that'd deal with any number of cuts, I
probably would have just bought the oddball tap. But for a one-off of
not-rocket-science dirty hack spec, it was good enough. (I never
claimed to be a machinist, I'm just a guy with machine tools in the
basement).

Interesting. Did you use ordinary mild steel for the tap or drill rod?

Best wishes,

Chris

On Thu, 17 Jan 2008 04:53:09 +0000, Christopher Tidy wrote:
Dave Hinz wrote:

Once aluminum, once mystery-steel for a nut that was expected to have
about 3 uses ever. Lots of lube and it came out OK but I wouldn't
suggest it for a "real" project.

Interesting. Did you use ordinary mild steel for the tap or drill rod?

It sparked like it had some carbon in it but, I inherited a large amount
of "mystery metal". Sorry to not be a lot of help.

On that topic, anyone have a rundown of paint color codes for steel? I
don't know the vendor and last time I looked, I found about 4 different
standards referenced by various sites I found on google. So it's racks
of mystery metal, I'm afraid. For stuff with a spec, I buy to that
spec, of course.

On 2008-01-18, Dave Hinz wrote:

[ ... ]

On that topic, anyone have a rundown of paint color codes for steel? I
don't know the vendor and last time I looked, I found about 4 different
standards referenced by various sites I found on google. So it's racks
of mystery metal, I'm afraid. For stuff with a spec, I buy to that
spec, of course.

As you've already discovered -- each vendor has its own color
code standards. I could look up the standards for Jorgensen Steel
(because I have one of their older catalogs), but that would be useless
for any other vendor's steel, let alone those from an unknown vendor.

And there is a *lot* of codes to type in, so I won't do it while
I know that it would not do any good.

If you can find out who the original vendor likely was, you want
to get a copy of *their* steel catalog.

And -- if you get steel from another source, but know what the
steel is, *paint it yourself* to match the catalog you have, so you will
know later what it is.

If you can't find out -- just get a catalog from your own
vendor, and keep all newly-bought steel in a separated area.

Good Luck,
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 18 Jan 2008 05:15:56 GMT, DoN. Nichols wrote:
On 2008-01-18, Dave Hinz wrote:

[ ... ]

On that topic, anyone have a rundown of paint color codes for steel? I
don't know the vendor and last time I looked, I found about 4 different
standards referenced by various sites I found on google. So it's racks
of mystery metal, I'm afraid. For stuff with a spec, I buy to that
spec, of course.

As you've already discovered -- each vendor has its own color
code standards. I could look up the standards for Jorgensen Steel
(because I have one of their older catalogs), but that would be useless
for any other vendor's steel, let alone those from an unknown vendor.

It's a damn same too, I've got a ton or more of nicely marked mystery
metal.

And there is a *lot* of codes to type in, so I won't do it while
I know that it would not do any good.
If you can find out who the original vendor likely was, you want
to get a copy of *their* steel catalog.

TO go with the ton of mystery metal, is a ton of paperwork, some of
which might be a catalog. If they're all from the same vendor (a
reasonable assumption for starters), I'm wondering if spark-testing by
someone who can read sparks would be able to narrow down which vendor's
"red with a brown stripe" this stuff is.

And -- if you get steel from another source, but know what the
steel is, *paint it yourself* to match the catalog you have, so you will
know later what it is.

Seems like a sharpie and actual numbers wouldn't be a bad approach?

If you can't find out -- just get a catalog from your own
vendor, and keep all newly-bought steel in a separated area.

That's what I've been doing for important projects. Mystery-metal is
fine for some things, though, and I can't bear to just toss it...

On 19 Jan 2008 01:43:32 GMT, Dave Hinz wrote:
On 18 Jan 2008 05:15:56 GMT, DoN. Nichols wrote:
On 2008-01-18, Dave Hinz wrote:

On that topic, anyone have a rundown of paint color codes for steel? I
don't know the vendor and last time I looked, I found about 4 different
standards referenced by various sites I found on google. So it's racks
of mystery metal, I'm afraid. For stuff with a spec, I buy to that
spec, of course.

As you've already discovered -- each vendor has its own color
code standards. I could look up the standards for Jorgensen Steel
(because I have one of their older catalogs), but that would be useless
for any other vendor's steel, let alone those from an unknown vendor.

It's a damn same too, I've got a ton or more of nicely marked mystery
metal.

And there is a *lot* of codes to type in, so I won't do it while
I know that it would not do any good.
If you can find out who the original vendor likely was, you want
to get a copy of *their* steel catalog.

TO go with the ton of mystery metal, is a ton of paperwork, some of
which might be a catalog. If they're all from the same vendor (a
reasonable assumption for starters), I'm wondering if spark-testing by
someone who can read sparks would be able to narrow down which vendor's
"red with a brown stripe" this stuff is.

If you keep the lot all together, and find something that you
/really/ want to ID (I.E. the assay costs are far less than going out
and buying the metal new) find a junkyard with one of those nifty
X-ray Spectrometer (IIRC) metal ID guns.

You just put a 12-pack of chilled (or a fifth at room temp) potent
potables in the back seat of the gun owner's car as "payment", place a
small sample in the jaws, and press the button. You might not be able
to ID it to a precise compound if it was true mystery metal, but you
DO have a clue what it most likely is.

The gun gives you the component mix of carbon, manganese, lead, etc.
A hardness tester tells whether it's tool steel or spaghetti. Spark
testing would be another confirmation of carbon content. That, and
the old paperwork and vendor color chart would confirm what you have.

And -- if you get steel from another source, but know what the
steel is, *paint it yourself* to match the catalog you have, so you will
know later what it is.

Seems like a sharpie and actual numbers wouldn't be a bad approach?

Hell NO!!! Die stamps and a ball-peen hammer would be best, as long
as you don't plan to use every mm of it... Or paint marker. And if
it's hardened metal that would ding your die stamps, you can use paint
marker and a vibratory etcher as backup.

Sharpie fades and weathers off way too easily - when I want to mark
a power panel "permanently" I use a LaCo-Markal paint marker like the
junkyards use - the LaCo looks like a regular marker with a valve tip,
the junkyards buy the little squeeze bottle with a big ball-point tip.

Real paint that will hold up outdoors in the sun for 20 years and
still be readable (like the address a roof air conditioner belongs to,
or the unit number in large installs) - and if some bozo paints over
it you can still read the bump in the paint and reapply on top.

-- Bruce --