etching glass or mirrors

[turkgeltz]

Does anyone have any experience with doing etching in glass and how to do it? diamond bit? speeds and feeds? Wife wants.......

[steele]

I have no experience here BUT: Have you considered making a stencil over the glass and then blasting it with grit? Does she really need glass, could you use clear plastic?

[BIG AL]

Coat the glass with a layer of wax, lay your template over the surface and start punching thru the template with a sharp stylus, next use needle to remove the wax between the punch marks, coat the surface with sulferic acid, let sand and then wash off with lots of water.Tip, go to a Tandy's store and get some leather transfers and follow the directions. (this is what I do as I'am only able to draw flys). Best of luck! BIG AL

[turkgeltz]

Thanks, I'll have to give that a try!

[High Seas]

Geoff Williams, in his book CNC Robotics took the following approach:
1. Plot the image on the surface with a permanent marker that resists etching paste, He found that the Pilot Metalic Marker (extra fine) would work.
2. Then added a border around the plot with a wider version to prevent "spill over".
3. Let the ink completely dry.
4. Read the safety warnings on the paste.
5. He applied the paste with a small piece of wood (bet the caustic stuff eats up the metal bits in brushes)
6. He let it dry for 15 minutes (plus or minus based on brand of etching paste).
7. Wash off the paste and then clean off the ink with lacquer thinner.

There's been a lot of plus/delta said 'bout his book. But this looks like it might work!

You might find all the bits to do the same thing at a crafts shop (Michaels or JoAnns - chain crafdt stores) or a stained glass shop.
Jim
PS - if you want to buy the book - best bet I found was thru overstock.com

[keithorr]

Originally posted by turkgeltz Thanks, I'll have to give that a try!

Don't.

Sulphuric acid doesn't etch glass. Hydrofluoric etches glass. Very toxic.

[High Seas]

ROGER THAT!
I did a quick teoma search and there are some good hits on MSDS (safety data) and other options/info on pastes etc. I'm still prone to purse the xyz pen and ink (read CNC) approach to glass work - haven't yet, but will soon - rather than deal with more bits, cutting speeds/feed rates, etc on a pretty tough medium!
Mind you I hand-dressed 2 marble countertops by hand - so an easy way is a better way!
BUT - chemicals require care!
Jim

[keithorr]

The paste is a dilute floride based product. The thickener prevents splashing, and the low molar strength makes it safer to use than hydrofluoric acid.

The only problem with the paste is the etch can look patchy. Some areas more frosty than others. Reapplication doesn't always solve the problem.

Commercial glasses etch differently depending on the chemical composition of the material.

Most shops use sandblasting equipment. A fine grain of aluminum oxide with produce a lightly textured frost, closest to an acid etch.
Silicon carbide is much harder, and knocks very small chips out of the glass. (Easier to see with a magnifying glass.) Silicon carbide grit is better for deep carving.

[DLMACHINE]

What about milling glass? Can it be done?

[Konrad]

Would a Dremmel tool with a diamond bit work?
Konrad

[BIG AL]

Well your right, I feel even dumber than usual. Sulfric I used to etch metal, not glass, same method only different acid. My first thought for acid would have sent everyone in orbit as it only comes in a wax container. I do remember a shop that used sand in a unit that looked very much like an air brush, but the guy that did the brush work was a true artist. "Anyway this group proves that this is the best site on the web for solid info."

[DLMACHINE]

What if I wanted to make a 3D object out of glass how would you do this?