GetCrafty Craft Facts

Q: I was unaware that the AB coating was done in a vaccuum chamber. I thought the coatings were applied (metallic salts) then fired on during the manufacturing process. I also have never heard of coating companies. Can you send me some details? I think I can etch the beads if I find some with AB finish, but have never heard of being able to apply an AB finish after the fact.

A: One picture is worth a 1000 words, or at least 100. The bead is indeed a "druk" and the glass is quite common. It also is 'AB' coated which is a secondary process. Consequently, if you already have the beads, you might contact a coating company. The process does not require too high a vaccuum, and should not cost too much. The coatings you described are "Iris" coatings, gun-metal, etc. They too are done after the bead is made. There is another type of coating often called "Luster" coatings eg. 'Picasso'. Here, the bead is heated to about 300 C on mesh trays in an oven and a heated gas (1000 C+) is fed into the oven. Then, much like a fog, the gas condenses on the bead. If the trays are agitated, the beads get coated all over. As for a coater, there are several firms doing dichroic coatings. They would be able to easily do an 'AB' coating as it is much easier to do than 'Dichroic'. If not, they may be able to point you to one. I think there is a firm called 'Austin Thin Films' in Texas. You could also post a request in rec.crafts.glass. This is one of my favorite groups, as they seem to be more techinally oriented and "web savvy" than some of the others. Last, use the web search engines. That's where I would start if I wanted to find a stateside coater. I would suggest you do the etching before coating. This is the normal process for an 'AB' coated 'Matte' bead. Parenthetically, the 'Matte' finish for 'Druks' is not done with acids. The beads are simply removed before the final finishing.