Posted by Mike Jackson on February 17, 2004
Once in a while, you will get a small area that just won't chip. There are numerous ways of trying to force it to chip including making little dessicant "tents" and so forth. One safe way is to wet the glue, clean the entire piece of glass and remove all traces of glue. Then you can paint with asphaltum onto the clear glass beside the problem letter or design and use the squirt bottle or even pour glue directly onto the unchipped (but frosted) glass. The asphaltum will act as a chip resist, but just to be safe, I go ahead and cut and remove any glue that overlaps onto the asphaltum. By the next day, the problem area will usually chip and you can finish the job.
The photo above shows at least the concept of painting around a letter. It doesn't have to be neat, except along the edge of the letter or shape. In this particular piece, I was protecting the deeper etched groove, but the principle works the same if it had been clear right up to the chipped areas. You use the technique if you didn't like the first chip and wanted to do a double chip. Needless to say, it takes a little bit of basic brush skills. Asphaltum dries in a few minutes, so you can squirt the glue fairly quickly after painting.
As I tried to highlight in a post last night, it is difficult to "hurry" on a chipped glass project. That will often backfire on you. The lesson to learn is to NOT sell a chipped glass project with a short deadline. I'd suggest allowing twice the time you think you really need. It is nice when things go correctly, but hard to catch up if they don't.
Mike Jackson
Denver Chapter of the Letterheads