several people have written me to say they have heard about pencil marks as
a no-no, also. It may be significant that the words "sharp insrtument"
and "scratch" were also used. One example was also about 0.020 sheet metal,
having corroded under paint where it had been marked with a pencil. He
didn't say he had seen it, just that it could happen.
I will certainly concede that scratching a sheet metal panel, particularly
one of alclad metal, is bad. exposing the substrate of alclad by going
through the protective layer is to be avoided. However, I was considering
only the application of a pencil mark- which involves leaving a trace of
graphite on the surface, not cutting through anything. In this regard, ANY
marking method that uses enough force in a concentrated spot to leave a
mark consisting of moved metal is bad.
The original thread mentioned that the pencil mark would cause corrosion---
I have yet to see anything that substantiates that a mark alone will do this-
I am open to any explanation that does not involve cutting into the metal-
ie, corrosion caused by leaving a pencil mark- not a scratch- on the metal.
I really want to know, and to have non-anecdotal references.
Bill- W4BSG
-
Bill Aycock W4BSG
Jackson County, AL
EM64vr
W4BSG is "vanity" this time, but was
earned by exam in 1954, the first time.
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