Have you ever tried to paint exterior window panes? It is awful.

Currently, professional painters hang on a ladder, dip just the right amount of paint on to their brush. Then they carefully eye the boundary between the brush and the glass, slowly drawing the bead of paint over the pane.

Good painters can finish a 12 pane window in about 35 minutes. Windows are probably the only section of the house which can't be sprayed, because painters would rather not scrape the paint off of the glass, because it takes forever. Taping is also for amateurs and also takes for ever.

Here goes. At night turn off all of your lights. Then spray all of your windows with photoemulsive liquid, like the kind used in screen printing. After this is done, turn on the lights in your house. After 30 minutes or so, the photoemulsion should harden only where light hits it (the glass).

Go back outside and hose the unhardened emulsion from your windows. You should now have exposed mullions and hardened photoemulsion covering the glass.

You can now spray paint all of your window mullions without getting any paint on the glass, but getting it all on the exposed mullions.

When you are done painting and it has dried, then use deemulsifier to remove the emulsion from the glass.

Hopefully, This will leave beautifully painted window panes with none on the glass.

You should try it... I won't.
-- leinypoo13, Aug 13 2007

Emulsion Remover http://www.reuels.c...ulsion_Remover.html
[leinypoo13, Aug 13 2007]

Emulsion http://en.wikipedia...wiki/Photo_emulsion
[leinypoo13, Aug 13 2007]

Single coat paints http://www.paintedb...m/images/group3.jpg
[normzone, Aug 14 2007]

Is this of any help? Method_20of_20bulk_...g_20of_20Aeroplanes
[normzone, Aug 14 2007]

It's mad, but (+) for creative use of darkroom tools.
-- normzone, Aug 13 2007


[+]. Better make sure the windows are clean first, though.
-- MaxwellBuchanan, Aug 13 2007


The panes are the glass bits(these are also called "lights"). The wooden parts are mullions. All the wooden bits together are the frame. The whole moving bit is called a sash.

Rework some of your terminology and you might get more buns.
-- Galbinus_Caeli, Aug 13 2007


I like the idea, but wouldn't the deemulsifier remove some of the paint on the frames?
-- Srimech, Aug 13 2007


//The panes are the glass bits(these are also called "lights". The wooden parts....//

Rework some of your parentheses.
-- MaxwellBuchanan, Aug 13 2007


Thanks [Max], fixed.
-- Galbinus_Caeli, Aug 14 2007


//Good painters can finish a 12 pane window in about 35". //
sp "35'"
-- AbsintheWithoutLeave, Aug 14 2007


' can be used to denote minutes and " for seconds, though these are usually measures of arc (60' = 3600" = 1°).
-- ldischler, Aug 14 2007


I'm not sure this would work. Windows are normally painted with two or more coats, the top coat being a gloss. I think your de-emulsifier would not penetrate the paint to dissolve the photoemulsion.

Also, a good paint system (primer/ undercoat/gloss) is fairly thick. If I decide to scrape the glass rather than painting carefully in the first place, I usually have to run a scalpel around the edge first, otherwise the "green" paint tears and leaves ragged edges.

Might work with some single-coat paints.
-- MaxwellBuchanan, Aug 14 2007


[MaxwellBuchanan] You maybe right. The dried paint on top of the emulsifier would be hard to penetrate. You may have to use tons of emulsifier which would probably destroy everything and be very expensive. It would be interesting to see if there is a way around that.
-- leinypoo13, Aug 14 2007


I don't know how many modern windows are mass-produced - presumably quite a lot. So, let the window-makers also make a custom spraying mask.

For instance, the mask for a 12-pane window would consist of 12 flat rigid rectangles, connected by little hoops. You just press it against the window - the flat bits mask the glass, and the hoops connecting them stand clear of the mullions. Then just spray.

Or, better still, let the guy use a brush. He makes money, you get a nice finish, and everyone is as happy as bedbugs.
-- MaxwellBuchanan, Aug 14 2007


Another trick is to apply a facial mask to the glass, then peel it off later, with the paint attached.
-- Giblet, Aug 15 2007


i threw a bun at your window and ran. +
-- k_sra, Aug 15 2007



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