----- Original Message -----
From: Jeff McNeal <jmcneal@ohms.com>
> someone contacted me offlist with a reasonable question. How do I know my
> badge holes are original? The original old badges (which have since gone
> away) were on the lid when I bought it, and, like the rest of the car, I took
> the lid down to bare metal, so there's really no question that the lid is
> right, but the repro badges are wrong...
Hi Jeff,
The problem with many of the repro badges (particularly the cast script
types) is that the reproductions are re-cast from originals by a lost wax (also
known as investment casting) method. The process invoves cleaning and repairing
the original to an acceptable standard, using this to produce a rubber mould
from which a wax replica is made, then the wax badge is set in a kind of cement
(called investment). Once the investment is set, the wax is burned out in an
oven and the now empty investment is cast into in metal, usually a bronze of
some kind. There are several weaknesses to this process. Firstly, cleaning up
an original badge often results in loss of definition - this is not a problem
if an original NOS badge can be found, but often that is not the case. The
other problem which you are having is that there is inherent shrinkage when
each material is cast - firstly the wax and secondly the metal. As far as I am
aware most RTV moulding rubbers and the investment are pretty stable from a
shrinkage viewpoint. This means that the 'new' badge will be slightly reduced
in size compared to the original, with any mounting lugs consequently closer
together and no longer aligning with the fixing holes.
I know this doesn't exactly help with your problem, but hopefully it will
at least explain why the badges don't fit. My interest in all this? Well I
think there's a market for well made replica badging.......
Cheers,
Bill.
--
Rarebits4classics
.......just what you've been looking for
PO Box 1232
Calne
Wiltshire
SN11 8WA
United Kingdom
http://www.rarebits4classics.co.uk
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