Plexiglas mirror is Plexiglas that has a mirror backing on it. It is available in 7 different thickness’ from 1/16" to 1/4". The thickness that you will use will be determined by what you are going to use it for. Personally I wouldn't go thinner than 1/8", and I would only use that for small panels - 2'x2' and under, as it is quite flexible - the same as Plexiglas. Most glass shops can order in plexiglass mirror, but your better bet is to get it from Laird Plastics (they have offices across Canada & US).

I know of 3 links to blasting equipment - though I'm sure there are plenty.

I was sent this one: http://www.kehm.com/empire.htm
I use the San-Blast line sold by Truman's, Inc in Canfield Ohio (they have some technical information on their website, and a complete line of siphon/pressure guns in their catalogue)
And Armor Etch has blasting systems.
Rayzist and PhotoBrasive also sell complete blasting booths if that is what you are looking for.

“Were I to locate a gun locally, will the tips sold by most vendors be generic enough to fit on most 3rd party guns? E.g., is there any uniformity in threading sizes which might permit purchase of a gun locally, and then fitting it with smaller tips to provide for lower volume, high-pressure spraying?”

Most guns have their own tips the two different brands that I use, each tip cannot be interchanged. The San-Blast siphon gun has a set screw that holds in the tip. Their pressure system uses a tip held on by a nut.
If you can get a gun that will use ceramic tips (nozzles) the ceramic (while about twice the price of steel) will last 5-6 times longer, so actually it is cheaper... And if you want to really have them last, get a carbide nozzle.

I have had good results with both PhotoBrasive Image Pro resist and Aicello Photo Mask APM Film "Here in the UK there are agents for Rayzist stencils, have you used them and are there any others.“

Rayzist, is very similar to PhotoBrasive's product - about the same price too. The other company that I know of: APM out of Japan - I have used their films, and am very impressed with it (the big difference is that a sponge can be used to wash out the resist rather than just a spray unit - really neat if you just have a few to do, and like me don't have the spray unit set up all the time). Personally I found that the glue that APM uses is very difficult to use (it is supposed to be re-positionable, but it is very difficult to get a thin layer, and hence is harder to etch off) but I did find that the Photobrasive glue will work well with the APM resist.
"The equipment for making them using Rayzist is approx £1100 here in the UK. That includes a UV box and Timer, wash-booth and dryer. This seems very expensive for what it is. Apart from making my own, (which I suppose is also possible) are there any other ways of getting the equipment?“

Yeeks!! That's expensive!! Allot of glass to etch just to cover the expense. I guess it depends how much you are going to use the resist. Yes it is very possible to make your own - I did it - the exposure light here sells for about $350 plus shipping - I made it for about $80. A washout booth, I just hang some plastic around a large sink, and spray away - make sure that you use a piece of mirror to clip the resist to when you are washing it out, it makes it much easier to see when it's done. Dryer - is a hair dryer, works well.
The above method gives you a chance to try it out with out spending a mint, and then finding that photostencil's not really the way you want to go.

I would suggest using one of the rubber or vinyl resists available. Personally I prefer the vinyl (easier to work with) but the rubber one will take much more blasting. For stage blasting, you can use just ordinary shelf vinyl (contact paper it is called - use 2 layers if you need) - it helps to draw out the pattern first, with a couple of different colours to represent the different stages of blasting. I don't know of any good books that have patterns for single stage and three stage etchings in them. I did get a book 15 years ago, but never used any of the patterns in it - I felt they were all so immature looking that I didn't want to waste my time on them... I would suggest that you make your own - they will be much more satisfying, and also uniquely yours.

Just about any design can be converted into an etched image. To make it opaque, there are two different things that you could do.
1. Etch both sides of the panels: have your image etched on the face, and just solidly etch the rear surface of the panel, so that it can't be seen through. You will be able to see shapes if there is a window behind the panel.
2. Do a two stage etching, so that your image is etched first - deeper and coarser - remove the remaining resist, and etch the rest of the panels just so that it is opaque.
What I suggest to people looking for design ideas, is to go to their local library - if you like flowers, look through some different books, and get some ideas, and concepts from the photos. Then take "artistic license" and make your design - it doesn't have to look exactly like the photo, just the general idea.

Unfortunately, once the glass is etched with the acid cream, there is no way of removing the etch.
Another thing you could try is to re-cover the etch with vinyl, cut out areas where the smudges are, re-etch, and incorporate the smudges into the design - though this might be impossible depending upon the design etched.

There is a vinyl available that replicates the look of etched glass - most vinyl lettering companies, or glass stores will have it available - check your yellow pages for a local company.

A couple of suggestions to start with:
1. Check with your local department of transportation, and just make sure that it is legal in your jurisdiction to do the etching - I know that some places are quite sticky as to what can and can't be done on vehicle windows.
2. Get an old window from a car, and try your hand at etching it before you actually start on your truck's windows.
3. You should just do a surface etch on the glass - don't go too deep, as it'll weaken or break the window.
Is your sand blaster a siphon or a pressure system? If it is a siphon, you should be able to use 40 - 70 PSI with no difficulty. If it is a pressure system, you should try it on a lower range - both these are dependent upon the stencil that you use - if you get a pre-cut stencil, follow their directions (pre-cut are available from many glass craft stores). Another way for you to get stencils, is to have a vinyl signage company cut them out for you, then you stick them on the glass, and etch - though as you probably know, you should cover any glass that you don't want etched (even with paper), as any overspray will etch uncovered areas. I have used the vinyl that is cut for signage with 80 PSI from a siphon blaster with no break down of the stencil (40 PSI from a pressure system). As far as sand is concerned, I would suggest using a grit size of between 100-200, with 120 probably being a good size - Magnesium Oxide works well, and is almost 1/4 the price of aluminium oxide. You could also use sand, or whatever you use for the bodywork - just as above try it on a piece of glass first, and make sure it's what you want it to look like.

The best way is to use a many toothed carbide tipped saw blade, on a table saw, or radial arm saw. Next best is a plywood saw blade, and finally it can also be done with a hand saw - again, the finer the tooth the better the cut. It should be cut before the protective covering is removed from the Plexiglas, and the cuts can be cleaned up by using a sharp hand plane, or a file. You have to be careful in cutting the pieces, that both sides of the cut are supported - otherwise when too much weight goes onto the piece that you are cutting off, it will snap the final bit.

Try contacting Arthur Montpetit glassman@ontarioeast.net He is a glass etcher in Ontario Canada that was putting together a CD of etching images for sale - I haven’t seen them, so can’t say what they look like.

I don't know of any special mirrors that are sold for this purpose, but there may be. I suggested to another person that was looking for something like this to try and use 1/8" plexiglass mirror, and bend it - a concave bend will make the image short/thin and a convex bend will make the image tall/fat. Laird Plastics is a nation wide supplier in the US, but don't know if they have any overseas offices.
Hope that will help you some. You might even want to try and email Laird Plastics, and see if they have any other solutions.

* Use a vinyl masking film that has been cut and weeded by hand or computer plotter, apply your design cut in reverse to the rear of the piece of glass or mirror that you wish to chip.
* Give the piece a light sandblast to remove the 'gloss' off the glass.
* Apply two thin pieces of plastic about 5mm square down the edge of two sides. These are the 'rails'.
* You need to melt the glue the same way you melt chocolate. Tip the glue into an old pot or tin and sit that tin in another pot full of water. Heat the water until the glue melts, and gets to around 70 degrees Celsius. You can measure this with a turkey thermometer..
* When the glue is melted CAREFULLY and QUICKLY pour it onto the glass on top of the resist. Get a scrap piece of plastic or timber and drag it down the rails you applied earlier. This gives you an even coverage of glue over the glass.
* Set aside and wait for the glue to 'gel'. It will dry similar to latex. When this happens get an exacto knife and carefully cut around the edge of the vinyl resist. Remove the glue that is sitting on top of the resist so that you only leave glue sitting on top of the sandblasted glass.
* The dried glue in 'latex' form can be remelted and reused.
* Sit the glass outside in full sun and wait for 12 hours or so!
* When the glue dries it contracts, and will randomly rip out scallops of glass in a feather pattern. Be careful, they are sharp. The length of time this takes depends on how hot it is.
* Another method it is get a garbage bag full of those little beads that you get inside your new shoes to absorb moisture. If you can get a whole bag full, you can seal the glass inside and the beads will absorb all of the moisture speeding up the process.

Well I hope that answers all your questions. Happy chipping."