In a message dated 97-01-28 16:38:32 EST, you write:
<< Hi, We are looking for a masking agent that is used to acid etch
steel. It looks and smells like roofing tar, but has a smooth
consistency and doesn't get hard at room temperature. From what I
hear, you coat a hob or die with this stuff and then squeeze it
in a press. The unmasked areas are etched while the masked areas
remain protected. If you continue this process, eventually you
have a finished hob or die. Any info that you can get about this,
especially how to make it, would be appreciated. >>
You're talking about ASPHAULTUM (sp?) It can be purchsed
through Rio Grande, and various other Jewelry supply venders.
Another place to find this product is at any PRINTING SUPPLIER.
I am not sure, but maybe even the local Home Improvement Center .
. . I haven't compared ingredients, but roofing repairs are made
by using a product with a similar name. I haven't tried the
product I found, so I am not sure of the results. Could the
'hardening at room" temperature problem be resolved by adding
mineral spirits to make the roofing tar a bit smoother?