[TheForge] Re: oil/wax finish, blackened steel

[Mike Spencer]

I like Brownell's "OxphoBlue". On pieces where some parts are forged
and some have as manufactured, I've had good results cleaning the
forged work with a wire brush and removing the mill scale from the
other parts with 6" 3M "Clean & Strip" (tm) wheel or the equivalent
(J. Walter makes a comparable product), then applying the bluing.

The advantage of the C&S wheel is that you use the edge and can
contrive that the very fine abrasive marks are parallel lines rather
than curves (rotary wheel) or randon squiggles (random orbit sander).
Since an unworked piece is typically long and narrow, the eye tends to
overlook fine abrasive lines along the long axis of the component.
The C&S wheel also works well on pieces of (say) 16ga sheet with
forged work around it.  The usual curved sander marks show up
especially well...er, badly on expanses of unworked sheet.

Phosphoric acid pickle also works to even out the finish between
forged and non-forged components before bluing but you probably don't
have time to mess with that before your deadline.  It's a little slow
on mill scale anyhow so it speeds things up to remove any mill scale
with a C&S wheel before pickle.

OxphoBlue is a cold blue.  Used to contain Selenic acid.  I think
they've changed the composition and *still* they won't ship to Canada
because because of the hazmat paperwork.  Luckily, I found a local
gunsmith who makes an annual trip to the US and he kindly fetched me
home 3 pints, which should last me more or less forever.

- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^