Do any of you knowledgable people know what paint is good for painting the numbers on numberboards so that they look white in daylight, but will let light through when illuminated from behind? There seem to be a bunch of options but if someone has figured out what works best then there is no need for me to try them all.

Thanks,
Roger

Belpaire@aol.com

Why don't you use white plexiglass or white glass (available at stained glass shops) and paint the background around the number? You can also cut a stencil out of brass sheet and mount that over the white background plastic/glass.

Richard

> Do any of you knowledgable people know what
> paint is good for painting the numbers on
> numberboards so that they look white in
> daylight, but will let light through when
> illuminated from behind? There seem to be a
> bunch of options but if someone has figured
> out what works best then there is no need
> for me to try them all.

> Thanks,
> Roger


richard.s.wilkens@boeing.com

I had thought about that, but from looking at photos I see that the numberboards are painted on the inside, which makes sense as paint on glass is probably pretty easily damaged. If white plexiglass was used, the black background would look hazy and the edges of the numbers would be fuzzy.

Roger

> Why don't you use white plexiglass or white
> glass (available at stained glass shops) and
> paint the background around the number? You
> can also cut a stencil out of brass sheet
> and mount that over the white background
> plastic/glass.

> Richard


Belpaire@aol.com

Try using two pieces of glass, one frosted and one clear. You can paint the number on the inside of the clear glass.

ironbartom@aol.com

I've made numberboards for a few of the locomotives at Railroad Museum of New England, using clear Plexiglass. My technique: Lay out the number in reverse, and mask the number. Then spray the background color (flat black spray paint works well), and let dry thoroughly. Wait a day, then apply a second coat. A third coat may be needed-- thinner coats work better than one thick one. Once the background color is dry, unmask the numbers-- looking from the front of the number board, you should now have a black field with a clear numeral area(s). Using flat white spray paint, paint the entire rear face of the number board, covering the black paint completely. Apply a few coats to even out the white. Painting the entire rear face white helps concentrate the light in the number box (the inside of which should be painted gloss white).

If the black field is painted on the outside surface, the black paint will be abraded and scratched when the locomotive is washed.

Individual EMD number "slides" are made from white translucent Plexiglass or white glass, with the black field painted on the front surface, leaving the numerals in white. The EMD number slides were used in number boxes that had a clear outer glass, which protected the number slides.

hpincus@mindspring.com

There is really only one way to make translucent white on black indicators (number boards) without using the steam engnine era method of black-painted, metal cut-out numbers in front of milk glass. This is to make a "reverse" stencil which consists of the number you want, stick this to the surface you wish to paint, apply a sufficient number of paint coats (3 minimum, 5 maximum), and peel off the number before the paint sets rock hard.

The most readily available self-sticking stencil material is plastic "shelf paper" for kitchen cabinets, which can found in supermarkets or multi-function dug store/marts.

The most common material the railroads used is white plastic, 1/8" if mounted behind glass (sometimes 1/16-3/32" for separate numbers), 1/4-5/16" if mounted exposed. Size also dictates thickness; the large the "board" the thicker it usually is.

Trace your numbers on the "shelf paper", cut them out with an exacto knife, stick them on your plastic, and spray the paint. I recommend these new epoxy enamels which come in spray cans. Spray 3-5 coats; 2 won't last more than about 5 years in daily exposure to sunlight. You don't have to wait overnight between coats because if you lay the plastic face-up, you'll be painting down-hand on a horizontal surface, so gravity won't be able to make the paint sag. Allow the paint to "surface dry" between coats (this means dry enough so a light touch with your finger takes off no wet paint and barely leaves a fingerprint).

Sometimes the railroads painted the numbers directly on white glass. This is the least permanent method because the paint doesn't really stick to the glass.

I've made quite a number of numberboards using this method, some for shortlines, which have then been stolen. If I ever see my work which has been so taken, I will reposess it.

I just want to thank everyone who responded to my question. With your help I now have a set of numerboards which came out quite well. I really appreciate the help and am glad that there are people who are willing to share their knowledge.

Roger

Belpaire@aol.com