A few years back the one my father did at my parents home broke. I decided to replace it with a framed mirror one. Put the contact paper and made all the cut outs and then let it sit. I found it last year and finished it. Lesson two: The longer contact paper sits on a surface the more adhesive sticks to the surface. I think I peeled off pure vinyl and all the adhesive stuck to the mirror. I used a quart of goof off to remove all the adhesive. It was given as a Christmas present last year to my parents. My siblings all wanted one.
I had enough etching cream for three more. I was not going to buy any more because the stuff is expensive and I really do not like working with glass. So learning from past experiences I used the contact paper I had left over and did three more in about two weeks. Lesson Three: As contact paper gets older, the adhesive does not stick well to the vinyl. This is a little different than lesson two. As I was cutting out the contact paper for the etched sections not all the glue came off with the vinyl. leaving a little bit of residue. I cleaned most of this residue up. The etching solution did not etch the mirror where there was glue left. Most of these are small little dots, so to appear to be beauty marks of a handmade piece.
I also made all the frames for these nativities. These are beech, stained ebony with a coat of shellac. The frames came out nice even though I hate to make miter stuff. I only had one of the three frames be a problem. So in conclusion, lesson learned: No more glass etchings.