[TheForge] Forging Chrome plated bumpers

Fri Mar 22 12:56:01 2002

Here's a link that gives some information on decorative chrome plating.  =
It's worth a look.

http://www.finishing.com/faqs/chrome.html=20

In light of the thinness of the layer of chromium on decoratively plated =
metal, it's unlikely there'd be anything left to polish once it came out =
of the forge.  You could try.

Chromium got it's name because of the highly colored compounds it forms.  =
So what you're likely to get out of the forge is a colorful piece of =
metal.

Since nickel and stainless steel are often included in pattern-welded =
metal, it's possible that chrome plated steel would work as well.  Whether =
it would look any different than the underlying steel is another question. =
 Remember, the chrome layer is probably pretty thin.  (Probably not worth =
the effort.)

Lots of metals are treated with acid bath.  There's no worry of the acid =
coming out of the metal in the forge because it's not IN the metal in the =
first place.  Acid reacts with metal (sometimes) to make salts.  Those =
salts might be toxic.  Maybe they could fume (though it's likely that if =
they do the metal will be the toxic part).  However, such things simply =
won't be present on metal that looks like metal.  If it looks like rust or =
corrosion, then maybe the acid (residue) IS there. =20

Along this line there seems to be a popular notion, repeated in some =
blacksmithing books, that metals are somehow porous.  "Packing the edge" =
of a tool seems related to this notion.  Be that as it may, metals are not =
in general porous, which is not to say they never are.  Castings, in =
particular, can be porous.  Gas inclusions in the melt will give rise to =
microscopic bubbles in the structure of the metal.  Porosity can even be =
desirable in castings.  This is one reason that forged metals can be a lot =
stronger than cast.  But "porosity" in, for example, structural steel =
would be equivalent to cold shuts or fatigue cracking =AF a very bad =
thing.  SURFACE porosity is another matter.  Defects, scratches, inclusions=
 from casting or rolling, are all quite possible.  This is why critical =
surfaces are always machined down to solid metal. =20

You're right.  Almost any smoke or fumes are dangerous to your health.  =
Don't breathe them.

Bruce
NJ

>>> Dave Bendall <[email protected]> 03/22/02 10:14AM >>>
     There's a shop here in Phx. that has piles of old chrome bumpers,
too, that's always gotten me wondering about forging them. My questions
are, assuming there's a safe way to forge this stuff, would the chrome
stay on after forging? Like, after you mangled it into whatever, could
you re-polish it to chrome-y brightness? Also, would it be possible to
forge weld up a billet of chrome bumper pieces for damascus purposes?
Seems like chrome layers would be pretty neat looking. Anyone ever
tried? I've always understood that chrome plated stuff was dangerous to
forge because of the acid bath if goes through in the plating process.
Heating  it causes the acid to come out in fumes. For that matter, ANY
smoke or fumes have got to be bad for you to some degree or other.
     Dave Bendall in Phoenix

_______________________________________________
http://mailman.qth.net/mailman/listinfo/theforge=20
theforge mail list group photo site is
http://www.photoaccess.com=20
Login:  [email protected]=20
password:  anvil
___________