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Frosted Glass
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Author:  David Woodbury [ Fri Nov 16, 2001 9:31 am ]
Post subject:  Frosted Glass

Based on my recent efforts, there are two ways to achieve frosted glass. The first is to go to the hobby/craft store and buy some goo and slather it on. The instructions tell you not to try it on larger projects, but to use it with a stencil for a decorative effect. Notwithstanding that, you try it anyway on a pane and the results are good in the kind of effect you get, but bad in the overall appearance- streaks and gaps.
The second is to go to your neighborhood monument supplier and have him sandblast the pane. This produces an even finish, but rather coarse appearance-kind of like coarse sandpaper. Of the two, neither cheap by the way, sandblasting is my preference. My glass supplier tells me that all frosted glass is sandblasted not "acid etched".
My question is whether there lies a middle ground which will produce a fine opaque finish that is even and pleasing to the eye. Has anyone tried this?

wrj494@aol.com

Author:  T.J. Gaffney [ Fri Nov 16, 2001 12:59 pm ]
Post subject:  Re: Frosted Glass

> Based on my recent efforts, there are two
> ways to achieve frosted glass. The first is
> to go to the hobby/craft store and buy some
> goo and slather it on. The instructions tell
> you not to try it on larger projects, but to
> use it with a stencil for a decorative
> effect. Notwithstanding that, you try it
> anyway on a pane and the results are good in
> the kind of effect you get, but bad in the
> overall appearance- streaks and gaps.
> The second is to go to your neighborhood
> monument supplier and have him sandblast the
> pane. This produces an even finish, but
> rather coarse appearance-kind of like coarse
> sandpaper. Of the two, neither cheap by the
> way, sandblasting is my preference. My glass
> supplier tells me that all frosted glass is
> sandblasted not "acid etched".
> My question is whether there lies a middle
> ground which will produce a fine opaque
> finish that is even and pleasing to the eye.
> Has anyone tried this?

There is a technique that we are using on our former Grand Trunk Combine. As so many of the original clearstory windows are missing in our car, we used the few original frosted windows as a pattern for a computer-scanning. We are then using a vinyl-like material to achieve the acid-etch/ frosted look. We have been pleased so far with our test case; I will let you know on the finished product.

TJG


Port Huron Museum
tjgaffney@phmuseum.org

Author:  Jim Lundquist [ Fri Nov 16, 2001 1:00 pm ]
Post subject:  Re: Frosted Glass

yes, on the toliet window of the AT&SF #1509, we used sandblasting for frosted glass.

Looks great at 90!

JimLundquist55@yahoo.com

Author:  Rudd [ Fri Nov 16, 2001 3:49 pm ]
Post subject:  Re: Frosted Glass

I have blasted some large storefront windows in a commercial building. I used fine grit, a large aperture nozzle, a large blaster, and plenty of air. Even-ness is achieved by these things and by even and THOROUGH application - the windows I had blasted were broken in a storm, and the replacements I saw a couple nights ago looked just plain bad - uneven/streaky etc. Blast the thunder out of it, but evenly.

A good supplier SHOULD be able to supply you with pre-blasted glass. Your monument guy, used to blasting stone, prob. used coarse grit sand.

Acid etched produces a completely different effect than blasting, it looks kinda looks like flakes of ice or some such.

You might also be talking about a product called privacy glass that is manufactured with a texture on one side - ask your glass supplier about it.
Prob. goes w/o saying, but whatever you do, put the "textured" side on the inside so it doesn't collect as much dirt.

Hope this helps.

rudd@cogdellmendrala.com

Author:  Dave [ Sat Nov 17, 2001 9:18 am ]
Post subject:  Re: Frosted Glass

Couple low budget alternatives:

Theatrical tradition - cut the design in a sheet of Roscolene Frost gel and sandwich between two pieces of glass. Or, adhere to one sheet if its out of hands reach.

I haven't done this but I am told one can silk screen "frosting" on glass to do repeated patterns.

Dave

irondave@bellsouth.net

Author:  Pete [ Sun Nov 18, 2001 12:01 am ]
Post subject:  Re: Frosted Glass

One big drawback to using etching paste to frost glass is that it contains fluorine salts, and it doesn't give a good opaque frost. Ths stuff smells vaguely like molasses. Don't use it indoors.

Author:  Howard Gorin [ Mon Nov 19, 2001 4:01 am ]
Post subject:  Re: Frosted Glass

> One big drawback to using etching paste to
> frost glass is that it contains fluorine
> salts, and it doesn't give a good opaque
> frost. Ths stuff smells vaguely like
> molasses. Don't use it indoors.
Any glass etching chemicals using fluorine salts or especially hydrofluoric acid is DEADLY. Do not use it if good health and long life is a consideration. Sand blasting only exposes you to silicosis. Let someone qualified do your sand blasting

hgorin@ix.necom.com

Author:  Evan [ Mon Nov 19, 2001 10:40 am ]
Post subject:  Re: Frosted Glass

At the ARM/TRAIN meeting, someone was talking about a technique where you apply a certain kind of glue to one side of glass and then bake it in a kiln. The glue flakes off, taking flakes of glass with it. Now that I think about it, this was mentioned at the ARM Parts Committee meeting. If you want more information on this technique, send a note to Rod Fishburn.

TMNY
webmaster@tmny.org

Author:  Pete [ Tue Nov 20, 2001 12:13 am ]
Post subject:  Re: Frosted Glass

> At the ARM/TRAIN meeting, someone was
> talking about a technique where you apply a
> certain kind of glue to one side of glass
> and then bake it in a kiln. The glue flakes
> off, taking flakes of glass with it. Now
> that I think about it, this was mentioned at
> the ARM Parts Committee meeting. If you want
> more information on this technique, send a
> note to Rod Fishburn.

This is called "chipped glass" and was widely used in banks etc., and the treated surface sort of resembles the impressions left by leaves or slow forming ice crystals.

One side of the glass is sandblasted uniformly all over, coated with a film of hide glue, then left in an oven "face up" overnight (or longer) where the drying glue peels slivers off the surface of the glass in a random pattern. Ambient humitidy, oven temperature, and concentration of the glue are important--it's sort of an art. It also depends upon the type of glass. Many years ago, I took a piece of pre-sand blasted replacement glass for a clerestory window to a company which made chipped glass (1" clear border around the chipped area--"fake" beveled glass). The glass chipped "in one big chip", and the guy said he never had seen this happen before--this was a production shop. I've also heard that alum is mixed in with the glue, but he didn't do this.

Author:  David Woodbury [ Tue Nov 20, 2001 9:27 am ]
Post subject:  Re: Frosted Glass

> This is called "chipped glass" and
> was widely used in banks etc., and the
> treated surface sort of resembles the
> impressions left by leaves or slow forming
> ice crystals.

> One side of the glass is sandblasted
> uniformly all over, coated with a film of
> hide glue, then left in an oven "face
> up" overnight (or longer) where the
> drying glue peels slivers off the surface of
> the glass in a random pattern. Ambient
> humitidy, oven temperature, and
> concentration of the glue are
> important--it's sort of an art. It also
> depends upon the type of glass. Many years
> ago, I took a piece of pre-sand blasted
> replacement glass for a clerestory window to
> a company which made chipped glass (1"
> clear border around the chipped
> area--"fake" beveled glass). The
> glass chipped "in one big chip",
> and the guy said he never had seen this
> happen before--this was a production shop.
> I've also heard that alum is mixed in with
> the glue, but he didn't do this.This isn't the frosted glass that I started this thread on, but a different product. I had and still never have seen it other than in clerestory windows. When I started work on the 1246, all this glass had been broken out. I took a fragment to my local supplier not thinking there was a prayer of accurate replacement. He was familiar with it and explained how it was made and that it was known in the trade as "glue chip" or "double process chip". Within a few days, I had all I needed cut to size for $2.75 per pane. I still have a few old panes from other clerestory windows. They need cleaning off which is not easy on the flaked side. If anyone wants any, let me know.


wrj494@aol.com

Author:  Owen Paulsen [ Tue Nov 20, 2001 6:40 pm ]
Post subject:  Re: Frosted Glass

When until need outside on a car is need the FRA Part# 223 22bul and engraved with the 223 type style.
This application the passenger car,railroad caboose,locomotive.
Keep this is mind.

Smile

Stan

owenpaulsen@att.net

Author:  Pete [ Thu Nov 22, 2001 2:32 am ]
Post subject:  Re: Frosted Glass

>They need cleaning off which is not easy on the flaked side.

Soak the whole piece of glass in a mildly strong solution of caustic soda (sodium hydroxide) or laundry detergent (Like Tide or All) for a few days, then clean with a stiff bristle brush. The solution is re-usable.

If you are unlucky enough to have glass painted with modern synthectic paints (alkyd enamels and newer), and you find this doesn't work, try brake fluid or commercial grade paint remover instead.

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