FYI
-----Original Message-----
From: Wayne Graefen
[mailto:wgraefen@xxxxxxx]
Sent: Tuesday, September 12, 2006
8:17 AM
To: David Homstad
Subject: Chassis Black, frames
NOTE: Also see 'Body and Paint - Factory Body
Assembly and Paint Application'
Early in the 300C production year, the assembled
"rolling chassis" (less motor, transmission, propeller shaft and
brake lines) was given a light spray of an asphalt-based product known
industry-wide as "chassis black". This was to minimize corrosion on unpainted metal components
while cars were shipped or sat in dealer inventory.
It was applied
only to the front and rear suspension areas only, by workers above the chassis,
such that often undersides of parts received minimal coverage. This coating obscured some information
such as stencils or inspection marks (see 'Markings').
"Restoration",
particularly for judged shows, rarely includes this type of protectant because
individual parts are far more carefully prepared and finished with paint or
plating than was ever done in a factory assembly line situation.
Nevertheless, cars built in the
first part of the year should have their chassis painted with chassis black to
appear as they did when they left the factory.
It is believed that there was a
production change in June of 1957 affecting the appearance of the chassis when
cars left the factory. A June 6,
1957, Technical Service Bulletin was issued regarding Dodge passenger cars
stating that "spraying of the partially assembled chassis" with
chassis black would be "eliminated". We can assume this was a corporate-wide cost- saving measure
and that similar bulletins were issued in all Chrysler divisions.
The Dodge bulletin goes on to
state that the following component parts are not painted and that these parts
were on the chassis prior to this point the spraying operation was performed. These parts "are either plated,
painted, or chemically surface treated prior to assembly, or are of metal of
heavy gauge which requires no further protection to prevent severe loss of
strength due to corrosion".
• Sway
bar
• Front
struts
• Upper
& lower control arms
• Exhaust
pipes
• Mufflers
• Tail
pipes
• Gas
tank
• Bar
spring anchor (torsion bar anchor)
• Steering
knuckle tie rails (tie rod adjustment tubes)
• Links
over arms (upper control arm brackets)
• Propeller
shaft & U-joints
• Differential
carrier housing
• Rear
spring U-bolts and shackles
Differential carrier housings
have been noted in red oxide primer.
These may have been painted prior to factory assembly or may have been
factory warranty replacement units that would have had to have been painted to
extend warehouse shelf life of appearance.
NOTE:
Because bare steel rusts just from the humidity in the air, for your
restoration you may desire to coat the above listed parts with some type of
preservative. Products from Eastwood Company called "Nyalic" (clear
sealant), "Spray Gray"(spray paint), or "Heavy-Duty Anti
Rust" (brown wax film) are available in aerosol form.
Without availability of a similar
Chrysler Bulletin as the Dodge item noted above, it can not be conclusively
said that all 300Cs built prior to June 6th, 1957, should be restored including
an application of chassis black, or that cars built that date and later should
omit a coat of chassis black.
However that is a probable assumption from research to
date.