I’ve used dish soap on pub glasses and it worked great, but have no experience with AB coatings…
2 Likes
For the “‘reverse painted’ intaglios,” masking and then engraving in stages by paint color may make it easier. That could also be something that requires accurate repeatability, though. If you want to try that, I’d figure out how to use the 12x20 artboard thing first.
2 Likes
bluetack or whatever color it is now?
For a mold/jig, you can use pretty much anything safe that dries/cures if you put a layer of cling wrap between it and the glass (either non-pvc cling wrap or trim back later). Plaster of paris comes to mind, although spackle would likely do. You won’t get a perfect mold, but it should be good enough to sit in.
Can even put a thin layer of Vaseline on the cabs and bake the polymer clay “jig” with the cab in place – then pop free after cooled…
Another option is silicone rubber paste mold making material – just set the proper sized cabs in it, and pop them free after it sets. This would avoid any possible accidental lasering of the polymer clay and any PVC component…
6 Likes
Most PVA/PVAc products should be fine, as far as I know, but it’s best to always check the MSDS for the particular product in use in case they’ve added some unusual ingredient.
1 Like
Grab a piece of scrap 1/8 inch and laser some different sized holes, then just place a couple of your “stones” and see if that holds them steady enough. If it works you’ll know what size to make the holes for a holder. If it doesn’t work you still got to play with a laser for a few minutes 
2 Likes
If the bottoms are flat you’ve won half the battle. It looks like they are sized/shaped similarly, but I bet you’ll need a little bit of “give” in your fixture jig. Maybe something like the lil’ mockup I made would hold them tightly enough that they won’t be sliding around, but be flexible enough for slight shape variations.
If this was cut into something thick enough, I imagine it’d also work when the cabochons are sitting on the bed round-side-down.
PS I can’t fix the awesome texturing job I did as I’ve already closed Rhino, but I’m thinking the bendy parts would work better if the grain was running the other direction.
11 Likes
Double sided tape was my first thought as well.
2 Likes
This would work great for plain glass cabs, but both the AB finish (front) and foil coatings (back) on these are relatively fragile; I suspect that tape would damage those finishes. In the future I may experiment with removing the foil on some before etching - may try the tape idea on those.
1 Like
Here are my initial attempts with the cabs. Clearly, my approach needs some fine tuning, but I learned a few things along the way and that much is good:
Placement shows the order of attempt, from left to right, top to bottom. The first row was done with a wet towel, and I found design placement very challenging with that method. I also realized quickly that finer lines seem to work better, so I switched up the clip art.
In row 2 I started using the dish liquid, which worked very nicely and also afforded easier image placement. By the last two cabs in row 2, I’d also refined the settings a bit more (though they still need more tweaking). I was able to follow in @jamesdhatch 's footsteps a bit, using settings similar to the ones that he used for his glass tiles (low power/high LPI).
Row 3 is where I started playing with reverse etching. These results are still a bit too grainy for my liking, so I’ll keep tweaking settings. Part of the issue may also be how the etching is interacting with the foil. Since I have buckets of culls with damaged foil, I’ll remove the foil from a few of those and try doing some unfoiled engraves to see if that changes anything.
These are some of the larger stones that I have in this style, so they’ve got a decent bit of weight to them. Thus, I was able to go jig-less (which my autocorrect wants to change to “jiggles” 
) for these quickie attempts. A couple of the stones did shift around a little, so I’ll definitely need to sort out the jig concept before moving down to any of the smaller sizes.
25 Likes
Is the AB coating as fragile as you feared ?
I’m a bit surprised if it is, given that the beads must spend most of their life rubbing each other, and that sort of wear would be a big no-no, commercially.
John
2 Likes
Have you tried some kind of color fill-in on the reverse etching?
2 Likes
Wow, these are SO COOL! I really appreciate the sharing of experimental results people are doing.
2 Likes
I just “sacrificed” one by taping it and then peeling it off real fast. The aurora borealis coating remained stable … though I have seen these coatings react poorly to too much handling in the past (so maybe that has to do with oils from the skin?). The gold foil at the bottom is generally pretty stable, but can be scraped or chipped off, and these little “fleabites” (actual industry term) can sometimes be seen through from the front… which is why I’m wary of taping the back.
Well, they do rub against one another in the original packaging, which is sort of a paper envelope that holds all of the stones all jumbled up against each other. That packaging method has always seemed impractical to me 
. But when they’re in use, they really shouldn’t rub up against each other. These are flat backed cabochons, which are typically set in bezels of some sort. They’re not actually beads (since they don’t have any holes for stringing) so they shouldn’t rub up against each other once they’re worked up.
(I feel like I did a poor job of explaining that, but hopefully you get the gist.)
The finish is fairly stable, just doesn’t do well with extreme handling. A bit of useless trivia: the aurora borealis finish was first developed by Swarovski in the mid 1950’s. These particular stones were manufactured in the 60’s - 70’s, so the process was still relatively new. Today’s AB finishes tend to be more stable, though that may have less to do with manufacturing improvements than the fact that they have not (yet) been subjected to age/wear/varying storage conditions.
7 Likes
I want to! Though I think I’ll need special paint for that (at least for any real color longevity). Have been buying a ton of new supplies, and need to slow down on that a little, but I’ll probably order some glass paints once I get the etching process dialed in a little better.
2 Likes
Somewhere else in the forum I mentioned that I have 50kg of beads to dispose of.
Looks like that might suddenly become slightly less now !
Thanks for the inspiration.
John
5 Likes
Nice fixture mock-up (curious why you chose jig…fixture holds work piece, jig holds workpiece and guides tool…at least that has been my understanding). Don’t forget the stress-risers in the sharp corners! 
1 Like
That’s my understanding as well. I’d also normally call it a “fixture”, but it seems that “jig” is the preferred term here. “Jig” works.
2 Likes
what she said! 
3 Likes