Gel medium and cloudingby aisling d'art ©2007
Many of us use gel medium in our paper and mixed media art, as both an adhesive and a sealer for the finished art.
However, gel medium isn't without problems. One of them can be clouding... when, as it dries, the gel medium never turns completely clear. It remains a little (or a lot) milky.
This doesn't happen very often, but when it does, it's very disappointing.
Early in 2007, my friend Storm asked about Golden gel medium. She said, "I was surprised when I used the [Golden] Gel Medium in my art journals it seemed to dry cloudy and it left ridges."
Storm also asked about Diamond Glaze, which several artists rave about. (I haven't experimented with it enough to comment, yet.)
Here's my reply to Storm's question about Golden gel medium on the ArtistsJournals2 list.
Cloudiness and gel medium
You are absolutely right. I saw that the first time that I taught in Florida. Humidity definitely seems like a factor in how clear the Golden gel medium is after it dries. It's also affected by how thickly the medium is applied.
This can be enormously disappointing if a finished work is permanently clouded.
I wish that I could offer a solution to the problem, but I haven't found one yet.
But, while that milky cast to gel medium can't be fixed, you can sometimes reduce the cloudiness from small air bubbles in the medium.
Tiny air bubbles in gel medium or other adhesives
Here's a trick if the medium seems to have tiny bubbles in it as it dries. In fact, this works for almost any glue, epoxy, or clear surface finish: Blow on it gently while it's still wet.
The bubbles will generally rise to the surface and pop. For deeply embedded bubbles, use a straw to focus your breath on the area around each bubble, but don't let the straw touch the gel medium.
Gel medium and heat
I use gel medium as the sealer on many of my collages. However, I know that it will soften again with heat... which is the principle behind some ways that we use gel medium as an adhesive.
This will be true for almost any acrylic-based product: They all melt with enough heat. This is a liability if you (or future generations) might store your art in a hot attic, or near a woodstove or radiator.
Alternatives to gel medium
I've tried clear polyurethane (not water-based) instead, but it can yellow sometimes.
Acrylic polyurethane is a little better than gel medium as a sealer, but it's not perfect.
I'm continuing to look for a sealer that's impervious to heat, remains clear and doesn't yellow. Diamond Glaze may be it. I'll have to test it more.
Meanwhile, I'm still using gel medium, and crossing my fingers.