Lettering on transparent panel

[GRollins]

Anyone got suggestions as to how to get clean lettering on the back of a glass or plastic panel? I want clear letters on a black background so they can be backlit by LEDs or bulbs, not black letters on a clear panel (which would be the easier route). I see stuff like this everywhere, but don't know how it's done.
Yes, I could call a sign-maker's shop, but it's Friday night and they won't be open again until Monday. Surely someone here will know how it's done and I can scratch my curiosity's itch sooner.

Grey

[KISS]

Educated guess:

Screen printing.

http://www.reuels.com/reuels/Silk_Sc...tructions.html

[GRollins]

I have silk screened things in the past. I had considered it for this, but I've got a couple of observations:
--The silk screen pigment, be it ink or whatever, is either thick enough that it retains the crosshatching of the mesh it was forced through...or if it was thinned enough that it would flow under the mesh, it was also thin enough to leak under the edge of the pattern I was trying to print. For a T-shirt, poster, or the front of a drink machine, that's not a big problem. For good, clean lettering, it's disasterous.
--The link assumes that you're printing to fabric, paper, or something similarly porous. There's no mention of anything that would adhere to glass or plastic.

Grey

[pinkmouse]

Use the clear film you can get for overhead transparencies, run it through your printer, and sandwich it between two layers of perspex.

[grimberg]

Grey,

Would something like this work for you?

http://www.glass-etching-kits.com/index.htm

[GRollins]

Al,
Yeah, that's kinda my fallback position. That's the method I use for circuit boards these days, so I already have the transparencies on hand. The problem is that the toner isn't completely black. I end up running two passes each on each of two transparencies--for a total of four layers of toner--and it gets difficult to register all four layers properly.
I'm also not sure what I'd use to glue the transparency 'paper' to the glass/plastic, although I'm sure that there are any number of glues that would do the job. Perhaps something like rubber cement.
The overall registering of the print within the glass/plastic would be a cinch, however. All I'd have to do is print a period in each corner, prick it with a pin, drill matching holes in the glass/plastic, and align the whole mess with a bit of wire driven through the stack.
It's just that I'm hoping for a more elegant solution.
grimberg,
I'm not looking to frost the glass or plastic, just mask out parts. My intention is to have print something along the lines of, say, 14 point or so, probably no larger than 20 point. Not very big. It's going to be really easy to lose the clean, crisp edges on the letters. As far as I know, the etching stuff isn't capable of that level of resolution.
On the other hand, perhaps I'd be able to tempt gullible young things by inviting them to come see my etchings.

Grey

[Steve Eddy]

Originally posted by GRollins
I have silk screened things in the past. I had considered it for this, but I've got a couple of observations:
--The silk screen pigment, be it ink or whatever, is either thick enough that it retains the crosshatching of the mesh it was forced through...or if it was thinned enough that it would flow under the mesh, it was also thin enough to leak under the edge of the pattern I was trying to print. For a T-shirt, poster, or the front of a drink machine, that's not a big problem. For good, clean lettering, it's disasterous.

What size mesh were you using?

Many moons ago I had a very nice 600 mesh stainless steel screen and never experienced that kind of problem.

Got it from a large silkscreen supplier that also carried inks and screens for industrial purposes rather than just t-shirts and stuff. Expoxy inks, special resist inks for printed circuit boards, etc.

Wish I could remember their name. Did some quickie Googling and wasn't able to find them or anyone equivalent. But I think your key to success will be a good quality, very fine screen and the appropriate inks.

Ah! Here you go. Check these guys out.

CRS International

They've got the inks and very fine screens, though they don't seem to offer pre-made screens.

se

[SY]

With silkscreening, it's a matter of matching ink and image to screen, but more importantly, getting the screen bias angle correct, getting the tension high enough for a good snapoff, setting off contact, and choosing the right emulsion. There's no reason that you can't use a 325 screen and dry emulsion for any reasonable lettering job.

[GRollins]

Steve,
They have inks they say will adhere to glass and plastic. Might be an option. I wish they had it in something less than gallons, though. It's not like I'll be doing a thousand of these things.
I don't have a clue what the mesh was. It was a light, nearly transparent fabric, but that's all I can remember. This was thirty years ago or more.
SY,
I confess that I'm in conflict with myself over this. I love the way it looks, but have questions about long term reliability. I seem to recall hearing somewhere that McIntosh uses silkscreening to do their glass faceplates. They look nifty, but bubble after a while--and if McIntosh hasn't gotten it right after all these years, I'd rather do something else. Other manufacturers seem to do plastic (granted, I don't know if they're using the silkscreen process), but have not been around long enough to judge durability.
Someone with experience in plastics may pop up and say this is easy...just print such and such a film and heat-bond it to your Plexiglas. I don't know. How the devil do they do these drink machines with plastic fronts? Mass produced toys? Control panels in cars?
I'm trolling for ideas. Don't need colors, just black background with letters left clear. Preferably cheap. Don't honestly care if it's glass or plastic.

Grey

[Steve Eddy]

I'm going to try and get hold of my laser guy this weekend and see if he might know of a less messy and less expensive solution for this.

se