Vinyl on convex glass

[Robert Schwieger]

Looking at a number of 3'x3' convex glass panels to be gilded and wish to use computer cut vinyl for background black (gilder's black) probably applied with a roller and subcontracting this part out. Being BCS (before computer cut stencils) I would like to know which vinyl is a good choice...one that will release with a minimum of problems when removing the vinyl. This will require extensive weeding of the vinyl and consume some time so the above properties are desired.
I understand the softening of the black edges before gilding having done this in the past so this is not an area of concern.
I would have screenprinted this if the glass were flat as I have completed a number of larger projects using the screen.
Thank you for sharing your wisdom. Bob

[Roderick Treece]

Robert,
Are you doing the inside or outside ?
I have hand lettered a number of convex things in the past for vinyl shops that could'nt lay their vinyl down due to the compound curve.Not having had the displeasure of having to lay vinyl on convex glass I am only taking a guess at this. Unless your art work is very small I don't think you will be able to lay it down very well. You could of course come back after it is down and take an exacto knife and clean up the arts that did lay down well. Also try to do small pieces of the design at a time. That may help.
I use regular spray mask for all the paint masking I do.

Good luck

[Dan Seese]

Robert,

I've had great success with Gerber Mask - the regular tack, not the high tack. (High tack is difficult to remove from the glass.)

I also made the mistake once of using high-performance vinyl. It stretches when you remove it and it leaves adhesive residue.

You'll want to experiment a bit with the timing on removing the mask subsequent to painting. There is a point where it seems a bit too wet and then a point later where it dries and the gap between the glass & the mask bridges, causing the paint to lift from the glass.

You can also minimize the tendency of the paint to lift if, when removing the mask, you pull it AWAY from the painted surface rather than lifting up or lifting toward the painted surface.

Of course, having said all this the down side is that Gerber Mask DOES NOT STRETCH. So it may be a moot point if you're needing it to conform to a curved surface, as Roderick is pointing out in his post. Maybe there is a cast high performance vinyl which would have the conforming properties you'll need, but which also has a low tack and won't leave residue behind. (I don't know but perhaps someone more conversant with vinyl or a sign supply house can help you identify the properties you need.)

Good luck. Vinyl is a useful tool when you understand it's strengths & weaknesses and unique applications each have their own challenges.

Dan

[Roderick Treece]

Hi Dan !!!

Robert,
I've included a few photos for you . The first one shows a very detailed mask / timing demo that I did awhile back. I think the paint was tested every 15 min. The next photo is of a project I'm working on now. I think I pulled the mask after abut a 45 minutes. You can see 4 small squares at the bottom that are my test spots I did. If you do those maybe 10 to 15 minute ahead of the project you will know when it is ready to pull the rest of the mask up.

Everything was done with Avery Spray mask, one shot and hardner.

Roderick