Anomaly-free thin layer of wax -- how?

[jlafferty]

Hi,

I've been experimenting with applying a very thin layer -- about the thickness of a single piece of Scotch brand tape -- of microcrystalline wax between two pieces of glass. I'm so far having no luck.

I've tried the following methods:

Spacing the glass apart by placing small strips of tape between them, and then wrapping the two with tape, I've submerged the entire setup in melted wax. Problem: air gets trapped in the space between the glass and is near impossible to remove (without resorting to a vacuum chamber, which I don't have).

Pouring a small bit of melted wax on one of the pieces of glass which has tape at its edges acting as spacers, then placing the other piece of glass ontop and applying even pressure. Problem: though both pieces of glass have been pre-heated and cleaned repeatedly, subtle anomalies and stratifications in the wax surface persist -- these are a mystery to me and I'm at a loss as to how to better apply the wax.

Do any of you have advice as to what techniques I should use? Essentially, I need to sandwich a very thin layer of wax between two round (49mm dia) pieces of glass to act as a focusing screen for an optical device, and so it must be free of bubbles and superficial anomalies.

Thanks,

- jim