Smokebox number plate

[ccvstmr]

Following the thread on protecting polished metal surfaces, I decided the loco smokebox number plate needed some "enhancement". Decided this board would be the best place to find ideas and solutions.

After a white rough buff, the raised edging and lettering stood out nicely. Then, noticed the background black paint around the perimeter lettering and red paint around the center loco number needed attention. My idea was/is to blast the number plate (bead or powder). Apply paint to the background surfaces. Then, sand the number plate raised edges on a flat surface, followed by a light buff to polish. Question is...what have others used for paint in this application: ...enamel? ...acrylic? ...other? Keep in mind, there's a substantial amount of heat "soak thru" from the smoke box. Carl B.

[Rwilliams]

Appears to be a custom spot plate that was done as a lost wax casting or photo etched from a zinc based material. Hard to tell from the photo.

The base metal of the plate can make a big difference in what happens over time at heat works its evil magic.

Your plan to give it an abrasive blast job followed by some sort of heat resistant paint, finished off with some polishing of the raised portions certainly sounds like the proper plan of attack.

Any insulator washers between the plate and the front of the smokebox to lessen the travel of heat?

[jkimberln]

You could try VHT paint in a spray can. Get it at an auto parts store like O'Reilly. They have several colors

JerryK

[Kevin S]

I am going to give you another option to do it. After blasting, go ahead and polish it. Lay the part facing up, take something so that you can drip the paint into the areas you want it to flow. If any paint gets on the raised lettering take some acetone and a paper towel and wipe the top of the letter off. As for paint enamel will hold up to heat the best.
-Kevin S.

[powderhorn01]

Food for thought. Depending on what the base metal is, brass, or pot metal, if brass or copper, enamel it, then you don't have to worry about the heat. You can get powdered enamels in most hobby shops.

[Greg_Lewis]

I'd be nervous about blasting it. The metal could be too soft (zinc?) and you could end up making things worse. I'd use paint remover to clean it. I don't think the heat is as bad as you might think. I did a test some years ago of about a dozen engines and reported here that the typical temperature of the smokebox just behind the stack was in the 350° range. So check to see that what you use is good for that temp. Your local NAPA store probably has some engine paint that would be fine.

[jkimberln]

I'd be nervous about blasting it. The metal could be too soft (zinc?) and you could end up making things worse. I'd use paint remover to clean it. I don't think the heat is as bad as you might think. I did a test some years ago of about a dozen engines and reported here that the typical temperature of the smokebox just behind the stack was in the 350° range. So check to see that what you use is good for that temp. Your local NAPA store probably has some engine paint that would be fine.

Like I said above, get some VHT paint at the automobile parts store. It's good to 1200 deg F. Virtually any paint made with inorganic color agents will outlast anything with organic dyes. VHT is a ceramic bearing paint. Good for smokeboxes, backheads, etc. too.

JerryK

[little giant]

I would use automotive header paint and I would mask the inner circle and paint the outer ring. Wait a day or two, and mask the outer ring and paint the inner circle. After a day or two lightly sand the face on 2000 grit sand paper to remove paint and polish the raised surfaces. Place the sand paper on a flat surface and hold the part with light pressure and move in a circular "8" motion. As for the heat I used the steam gasket material left over from the steam chest, or cylinder. Don't use clear coat paint on hot surfaces it will turn yellow.

[Trainman4602]

Hi All

I have watched this thread with interest. Here is may thoughts and experience with number plates.

The number plate on the 1361 was CNC'ed by John Hudak. I originally had Robert Dustin make me a plate. It was so out of scale I would not dishonor the model by using it.

I have used Floquil model paint for many years. it is not only heat resistant but it come in railroad colors.

I don't think it is made anymore but some hobby stores still have a few bottles in stock.

After painting it with color I generally coat it with clear. The heat is no problem after all the smoke box only reaches around 300 degrees and if you have the plate out on some stations it stays perfect for years.

[ccvstmr]

Would like to start by thanking all those that offered their ideas how to redo a smoke box number plate. A mixture of suggestions were used to arrive at the finished result.

If you go back to the initial post, you'll see the number plate wasn't in the greatest condition. The raised edges and lettering didn't look so bad after a close encounter with a buffing wheel, but the back ground paint needed some major attention.

The "do-over" started with a good soak in a bath of lacquer thinner. A brass wire brush was used to scrub out stubborn enamel that remained around the perimeter letter. After wiping dry and blowing off excess dust, the number plate looked ready for a new face.

Adhesive backed vinyl scraps leftover from other lettering projects was used to make masks. The circle cut-outs were made with my trusty little gasket cutter. The center hole mask was cut large enough to cover the inner ring so the perimeter lettering could be painted. I tried to cut the mask for the inner circle a little smaller than the first mask, so the raised inner ring would be covered. As such, two different cut circle masks were needed.

The center of the number plate was covered (including the circle cutter pin hole) and the number plate spray with a black enamel paint. After several hours, that mask was removed and the paint allowed to dry longer. The 2nd mask was applied and the inner circle painted with red enamel paint.

After enough time to allow the enamel to dry, the 2nd mask was removed. The number plate was starting to good. (to be continued)...

[ccvstmr]

Smoke box number plate rehab continued...

With the masks removed, fine sand paper was used to remove the paint from the raised lettering and surfaces. Held the number plate upside down on my drill press table to do the sanding.

Whoops...and then disaster! All was going so well until I went to apply the Rustoleum Crystal Clear enamel spray. Within a couple minutes...the red paint wrinkled up. Was the red enamel I had too old? Was sufficient time not allowed for complete drying? No matter...it was time to do-over the do-over.

I thought the "red" used was perhaps a little too orange. So, another can of paint was purchased (Rustoleum Painter's Touch) with a slightly darker shade of red. Once again, masks were cut and the masking/painting process repeated. When the masks were removed, the number plate was hung by wire in front of the shop oscillating ceramic heater. The number plate got up to about 120 deg. F...and hung there all day (about 9 hours) to dry before letting it cool off for the night.

The next morning, the raised surfaces were sanded once again. The final sanding strokes were all done in the same direction. After the dust was blown off, the number plate was hung in front of the heater again for a few more hours. Figured with the now exposed metal edges around the raised surface...I'd give solvents/vapors one last chance to evacuate.

About 3 hours later...it was DO or DIE time! Several light coats of crystal clear enamel spray were applied to seal the number plate. The result...mission accomplished! Thanks again to all the guys providing input. Hope you like the end result as much as I do. What's next? Can't put that nice number plate on the face of a grungy looking smoke box! Need to blast and repaint the smoke box! Geez, this redecorating effort seems to spread out all over the place! Cheerz...Carl B.

[SteveM]

Whoops...and then disaster! All was going so well until I went to apply the Rustoleum Crystal Clear enamel spray. Within a couple minutes...the red paint wrinkled up. Was the red enamel I had too old? Was sufficient time not allowed for complete drying?

We use krylon on our pinewood derby cars. I have found that you need to re-coat every 15-30 mins until you have what you want. If you need to re-coat several hours or even the next day, you can't; you have to wait a few days for it to cure, or it will wrinkle, just like yours did.

Steve