Why we recommend the glass test.

The reason glass is a great way to evaluate a product is because it lets you see the dried product isolated from your surfacing. Any differences between the dry product on glass and the dry product on your surfacing will give you clues of what to look for on your surfacing that is giving you an unexpected result.

On glass, you can see:

• How a film-forming sealer flows out and adheres to a very difficult, non-absorbent surface. After curing, the film will be tightly adhered and difficult to scratch off with your fingernail.
• How a non film-forming sealer (i.e. Aldon "Same Day Sealer") and any of the other products dry on a non-absorbent surface so that you are only seeing the components of the product.
• How a sealer bonds to a surface (glass) that has no texture to "grip". Your surfacing will provide more texture than glass for the sealer to "grip".

The only requirements for the glass are that it be flat, clear and clean. We have found "Windex Original Formula" to do a good job of cleaning. The glass can be any size and shape available as scrap from your local glass store or picture frame shop.