Scratchboard is a delicate medium and requires a finishing varnish to help protect the surface once it is out in the world. There are many varnishes and sprays to choose from, but I have landed on Golden's archival varnish with a matte finish (pictured above).
[To be honest, I'm not even sure how I decided originally to try it (probably advice from another artist), but have tried a few others when I couldn't get my hands on this brand and have always gone back to Golden. This varnish comes in gloss, semi-gloss, satin, and matte finishes. I prefer the matte finish because it most closely replicates how the scratchboard looks when it is brand new - and I'm just not a huge fan of glossy finishes on most things.]
This spray varnish helps protect my finely detailed scratchboard artwork from additional minor scratches, dirt, dust, moisture, and UV damage. I have not had any issues with yellowing or other coloring mishaps - but I don't use color on my scratchboards and have only been using it for a few years, which is probably not long enough for signs of aging.
Finished and framed scratchboards are more durable than most people assume, but should still be protected with other packaging when shipping them or traveling with them (i.e. moving). They can be touched and handled without worry, but sharp objects or large gauges can still scratch through the protective varnish. I use glassine paper to keep other materials from sticking to the surface, cardboard to protect the entire surface of the board, and repurposed bubble wrap or foam for added cushion.
WHAT IT IS
Golden brand - Archival Varnish - Mineral Spirit Acrylic Aerosol w/ UVLS - matte
HOW TO USE IT
Best Practice > Follow the directions on the can
I typically put three layers of the varnish on each finished scratchboard, allowing ample time for drying between layers. Some larger pieces require more layers of varnish to achieve an even finish.
Spray from 9-12 inches away [this is a do as I say, not as I do piece of advice - with smaller pieces I usually spray much closer and haven't had any issues]
**Spray in a well ventilated area!!!** (I try to spray outside whenever I can because the fumes can linger for a long time indoors)
I typically allow 3-4 days for the varnish to dry completely before wrapping and shipping or framing a piece. I have found that the finish can still be a little tacky after just a day or two and things will stick to it when tightly wrapped or pressed into a frame.
IF THIS EVER HAPPENS TO YOU...
One time I was spraying several boards and nearing the end of a can of spray. The final board I was spraying had a white fog over the entire surface and, as you can image, I started to freak out a little, wondering how in the world I could salvage that scratchboard. Thank goodness my dad has a lot of experience with varnishes and spray finishes because he knew immediately what to do to fix it...let it dry and spray it again (with a new can of varnish). The fog went away with the new coat of varnish and all was right with the world again!
This has only happened to me ONCE and I've been using this varnish for about five years. I'm not sure why it happened that one and only time, but am glad to have had the experience and now know what to do if it happens again.
You can find the Golden Archival Varnish here.
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