(Topic ID: 57353)

EM Backglass Restoration Advice?

By Shapeshifter

10 years ago



Topic Stats

  • 8 posts
  • 5 Pinsiders participating
  • Latest reply 10 years ago by prae4
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    #1 10 years ago

    Can anyone help?

    Got a small area by the score reels on an EM that needs restoring - only 4mm but looks awful as paint I used does not bleed light. Common area as score reels bang this area.

    So, how do I match the white used ( Gottlieb 60's pin ) and get it to be see-through etc?

    I read this so do I need to buy special paint? Where?

    http://www.flippers.com/restore.html

    It is not pure white so does anyone know the exact color??

    Thanks

    #2 10 years ago

    I have tried what you did with mixed results. Yes, touch ups in this area are almost impossible to have blend in and be invisible. A bit extreme, but I read another thread where they scraped all the paint off and applied a decal of special type that worked well according to the author. Another thought would be to replicate the entire area with appropriate airbrushed color.

    #3 10 years ago

    Have you tried white transparent glass paint? Then it would need a silver/grey coat as advised by friend of mine.

    Surely someone has managed to do a good job......rest of glass is good. Wonder how BG resto do it?

    #4 10 years ago

    If I'm not mistaken, BG Resto is scanning a glass, recreating the artwork in vector, then destroying the original art by removing it from the glass, then using solvent inkjet to print new art back onto the glass. It's not really my place to elaborate further, but I'll just leave it at "I wish they would find a way to do this without destroying originals, especially when people are sending in stuff that is very minor."

    #5 10 years ago

    Doing touch up work on backglasses is really tricky stuff. Regardless of the paint or ink you're using you must deal w/ two variables - 1) the intensity of the color and 2) the opacity of the material. So imagine you were using watered down acrylic paint and airbrushed a very light amount onto bare glass. You would have both low intensity and low opacity. So when you shine a light from behind you would definitely see light coming through. However, the color w/ or w/o backlighting would be very pale (low intensity). Now as you airbrushed more and more paint, your color would become more intense but the area would allow less and less light to come through. Bottom line: even if you use the correct color you must gauge how much transparency you need against the paleness of the color. Perfect color at the wrong intensity will not look accurate. Does that make sense?

    It gets more complicated if you have a bg where different colors show through the glass when backlit. Like say there's an explosion on the bg. It looks white when unlit but when backlit it looks red as if a bomb had gone off. In that instance you would first apply white coats and then eventually apply red behind it to create that effect. That's hard b/c if the white coats aren't opaque enough the red coats will change the white color! It will look rouge. Tricky stuff.

    If you want to attempt a bg touchup here's what you do: first carefully clearcoat the back of the glass (many light coats to insure color fastness). After drying, scrape the clearcoat off the glass of the area w/ the missing paint. Carefully brush on liquid frisket around the border of the missing paint b/c you don't want your touch up to go onto the surrounding area or it will change that paint's opacity and look like a dark shadow when backlit. Now lightly airbrush the missing paint area. Stop, look at it from the front w/o back light then w/ backlight. The goal is to match the surrounding area under both conditions. Once done, very carefully remove the liquid frisket so it doesn't pull up your touch up area. Then finally clearcoat the touched up area to protect it.

    If you're unhappy w/ your work you can always remove the touch up w/ alcohol and you won't damage the surrounding area.

    Good luck!

    #6 10 years ago

    My Space Mission at one time had a small fire inside the head, and it burned soot up the front of the wood panel, inbetween the wood and backglass. Some of the smoke deposited on the back of the glass and can be seen as dirty looking spots in the illuminated paint around the score reels.

    I tried to clean the smoke, but ended up cleaning off the paint too. So I lightly brushed on some white very thinly to undo what I did. It ended up looking OK, but it was better before my repair attempt.

    It prompted me to do some experiments with airbrush. I bought a cheap ($65) Badger Model 350 Airbrush and did some test on a spare sheet of clear glass. (Picture frame glass). I experimented with laying out several thin coats of Liquitex pure white acrylic to see how it will do illuminated by the back, as if on a back glass with #47 stock light bulbs.

    The experiment went very, very well. The airbrush layed a very even coat and it looked comparable to the white around the score reels on the back glass.

    However, the paint around my score reels isn't ***that bad***. At least not bad enough for me to razorblade the original white mask off and respray new ones. I just don't have the guts to do it.
    But I definetly -would- try the tecnique to fix a badly damaged backglass. One that's FUBAR anyway. My experiments with airbrushing junk picture glass turned out that well.

    #7 10 years ago
    Quoted from prae4:

    Doing touch up work on backglasses is really tricky stuff. Regardless of the paint or ink you're using you must deal w/ two variables - 1) the intensity of the color and 2) the opacity of the material. So imagine you were using watered down acrylic paint and airbrushed a very light amount onto bare glass. You would have both low intensity and low opacity. So when you shine a light from behind you would definitely see light coming through. However, the color w/ or w/o backlighting would be very pale (low intensity). Now as you airbrushed more and more paint, your color would become more intense but the area would allow less and less light to come through. Bottom line: even if you use the correct color you must gauge how much transparency you need against the paleness of the color. Perfect color at the wrong intensity will not look accurate. Does that make sense?
    It gets more complicated if you have a bg where different colors show through the glass when backlit. Like say there's an explosion on the bg. It looks white when unlit but when backlit it looks red as if a bomb had gone off. In that instance you would first apply white coats and then eventually apply red behind it to create that effect. That's hard b/c if the white coats aren't opaque enough the red coats will change the white color! It will look rouge. Tricky stuff.
    If you want to attempt a bg touchup here's what you do: first carefully clearcoat the back of the glass (many light coats to insure color fastness). After drying, scrape the clearcoat off the glass of the area w/ the missing paint. Carefully brush on liquid frisket around the border of the missing paint b/c you don't want your touch up to go onto the surrounding area or it will change that paint's opacity and look like a Dark Shadow when backlit. Now lightly airbrush the missing paint area. Stop, look at it from the front w/o back light then w/ backlight. The goal is to match the surrounding area under both conditions. Once done, very carefully remove the liquid frisket so it doesn't pull up your touch up area. Then finally clearcoat the touched up area to protect it.
    If you're unhappy w/ your work you can always remove the touch up w/ alcohol and you won't damage the surrounding area.
    Good luck!

    Like a lot of things never knew there was so much to it and how much skill! Some great explanations and will try and get intensity and opacity....... Not easy!

    #8 10 years ago

    SteveFury made a really great point. Experimenting on a piece of glass is a good way to start. You'll see how much paint is too much or not enough. You'll also see how airbrushing vs. paint brushing is really the only way to go. The brush strokes create small ridges that look like rippling shadows when backlit.

    All in all this technique is good for large spot colors or blending small areas. As soon as you get into big multi colored areas or graphics you really have to go a different way (ie silkscreening, reprints, toner transfers etc.)

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