[Healeys] Parkerizing

[Curt/Nancy Arndt]

Charlie & interested list members,

My process is intended to duplicate the original black finish on many of
the Healey fasteners, i.e., most of the Whitworth fasteners and the
carburetor fasteners on the early cars.  The original process was called
"Phosphate and oil"  or "Phos & oil".  Here is an excerpt from a  series of
articles that I'm currently writing on British fasteners for Austin
Healeys...

*Chemically Blackened / Bluing*

This is an oxidizing process that leaves a blue-black appearance, and may
provide some slight protection against rust, in the case of steel. The
majority of the Whitworth (BSF) fasteners used on the BN1s and 2s
originally had this black phosphate finish.  *To replicate this finish at
home, see the supplement article on Blackening tools and fasteners.*



Note:  While the normal delivery condition of fasteners may sometimes be
referred to as Black Oxide, rarely is that the actual finish. It is
generally used in a broad form to distinguish them from plated fasteners.
The actual finish is more of a *phosphate and oil* (phos & oil)
preservation. Actual *Black Oxide* and *Parkerizing* are proprietary
finishes.


My local Jaguar and British car restoration shop uses a local business,
Black Oxide Services in San Marcos, CA for all of their bulk fasteners and
the look is close to my process, however the rust resistance is not as
good, and it's not cheap.

Here is a description of the various black finishing processes...

 *Black Oxide* Black Ferrous Metals Fair Chemical discoloration; combined
w/an oil dip. Rust resistance comes from the oil only.
 *Phosphate & Oil * Charcoal Grey or Black Steel Good Zinc or manganese
phosphate used with a rust-inhibiting oil dip.


Now to "Parkerizing", while the finish is more gray and sometimes has a
greenish tinge, since it is used as an alternative to conventional gun
bluing it should not affect the strength of the part.

Cheers,

Curt