Will UltraClear epoxy stick to a glass surface?

Not reliably. Glass is not a standard substrate for UltraClear Bar & Table Top Epoxy, and the epoxy does not naturally bond well to smooth glass. A full glass surface, whether a glass table top, a window pane, or the underside of a glass patio table, is not something we recommend pouring over, and we do not have an application guide for it.

The epoxy can adhere to some glass surfaces if they are properly prepared: lightly scuff or sand the glass, then clean it thoroughly before applying. Even with that prep, for most glass surfaces the answer is still no. If the glass is not prepared well, the epoxy will not cure in a proper layer and will likely fish-eye or delaminate. If you want to try it anyway, do your own research and test on a small piece of the same glass before committing to the project.

A small glass inlay in a wood table is a different situation. Customers have poured over wood tables with glass inlays without issues, because the surrounding wood gives the epoxy enough area to adhere to. As long as the majority of the surface is wood, it should not cause problems.

For the full list of surfaces the epoxy is designed to work over, see: https://ultraclear.helpscoutdocs.com/article/111-epoxy-surfaces