There are other products and acrylic-based finishes on the market that may work with polymer clay.
Below is a list of just some of the products that people have reported using to seal polymer clay:
- Translucent liquid polymer clay. (Different brands have different textures after curing.)
- Diluted white glue. (Not cheap, washable school glue.)
- Some types of clear acrylic (not enamel) nail polish.
- Jacquard's Pearl-Ex Varnish.
- UTEE (Ultra Thick Embossing Enamel). (Doesn't brush on. Granules have to be melted on. Works best on flat surfaces. Otherwise, you must use a Melting Pot. Is generally protected with a coat of Varathane.)
- DuraClear, from Deco.
- Two-part epoxy resin, such as Envirotex Lite and Aristocrat's Liquid Glass. (Works best on flat surfaces.)
- The following products from Golden: Polymer Medium, Heavy Gel, and Varnish with UVLS.
- Mona Lisa Goss and Satin Sealer, from Houston Arts.
- Liquid Laminate, from Beacon.
Any time you try something new or something that hasn't been used extensively by other polymer clay artists and hobbyists, you run the risk of future deterioration, so it's always wise to run a test. It may take months to complete tests to your satisfaction. However, without pioneers who were willing to experiment, we would not know that Varathane and Future work as well as they do. So run your experiments when you find something new-and please share the results with others.
In general, it is wise to avoid most spray-on, aerosol glazes. The propellants often react with the clay and cause the finish to never dry completely. If you need a spray glaze, you can water down Varathane (and Future) and apply it with a misting bottle.