Name: Ross J.
Date: 2001 - 2002
Hi! I am trying to complete an "engineering" project for
my Eagle rank in Boy Scouts. I am providing a number of signs for a local
Georgia nature trail, each with computer-generated text on a paper
backing, to be mounted on wood plaques. Can you help me identify a
sun-resistant, clear coating that I can apply to protect them? (I am
thinking about a polyurethane varnish, fiberglass resin, or a clear
epoxy, but I am not sure if these will not yellow, crack, or fade. I
contacted several tech support sites of both paint and fiberglass
companies, but none responded.) Many thanks for your help,
Without a clearer picture of how your panels are configured, it is
difficult to make detailed recommendations. But consider the following:
1. The inks must be light stable. This means carbon blacks, iron oxides for
yellows, reds and browns, phthalo blues for blue. Check out "Jerry's
Artorama" on the Web at
http://www.jerryscatalog.com for light stable pigments. Pigments used in
inkjet printers are not likely to be light stable. Art supply houses may
also carry lines of light stable pigments -- I'm not sure.
2. The papers must be light stable. This means an "acid free" archival grade
which are at the above source or other art-suppliers.
3. An exterior grade urethane would be a good selection to seal the wood
plaques, and there are ultraviolet-stable grades of Plexiglas you could use
for the front face to protect the printing and paper from ultraviolet light.
You can obtain these from most any glass supplier.
4. The Plexiglas, and the exterior grade urethane won't yellow, but you
should stay away from epoxies which generally do not fare well under
Hope this is of some help.
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Update: June 2012