I need new filters for my tricolor cameras. I have now found a place that can sell me the right gelatine filters. Only problem is that they cannot mount them between glass. I took apart one of the defective filters and can get the old gelatine out. Still need to see if I can clean it well enough.

The lady I had at the phone told me that they mount it between 2 plates with spacers in order to avoid Newton rings. Only thing is that I don't have spacers in the original filters. Also the glass is much thinner than what they use (they use 2mm while the originals are 1.4mm). So the plan now is to re-use the old glass.

But how do you mount those gelatine filters between 2 glass plates? The old ones were glued over the complete surface. I really have no idea what glue to use and even less of a clue how to do this without bubbles. Does anyone has an old book that describes how to do this?