Recently i was at an antique store they had for sale a builders plate for an Altoona Works 1935 P5A number 4274. At first I wasn't going to buy it because when they pulled it out of the case it was cast in aluminum I thought it was a fake. I was able to call the owner on the phone and I mentioned to him, i didn't think it was real. He insisted that it was, he told me that at first they were cast in iron and later in aluminum, so i bought it. I feel I made a mistake buying it because I looked online and I can't even find a P5A with that number can someone help me identify if this is a fake or the real thing there is nothing anywhere on the plate were it says its a reproduction.
Thank's

4274 is the construction number

sample photo's shown here

http://www.altoonaworks.info/pics/stuff/aw_4278.jpg
Original plate from a PRR P5a (modified) 2-C-2 built at the Juniata Shops.?
http://www.altoonaworks.info/pics/stuff/p5a_x2.jpg
Owner: L.R. Myers and C. Dallos
Examples of two P5a plates here, one from Westinghouse and one from the Altoona Works.

Your plate
4274 Jan-35 P5a Mod 2-C-2 PRR 4783 Oct-61 Westinghouse electrical gear

That might be a nice find!

Every authenticated GG1 builder's plate I have had the chance to handle has been cast aluminum--which is why, when I cast a few replicas from one of them decades ago, I used extremely heavy/soft type casting metal, so no one could pass it off as the real thing. (Having said that, I think the 4800's Westinghouse plate might be cast iron, but it's an anomaly in several other ways.)

And, yes, the builder's number doesn't match the loco number. The G plates I handled were Altoona Works 4300-series numbers.

Although it's not impossible it's a fake, the authenticity of the plate cannot be disputed merely on the basis of the number or aluminum. Condition can be variable as well--the one plate I cast replicas from had been removed by a Wilmington Shops employee and given discretely to a Presbyterian minister in Wilmington who was a hardcore PRR fanatic, and had been "cleaned up" to good-as-new by said employee in the 1960s before "transfer."

The blanket statement that all GG1 plates were aluminum is not 100% correct. It is known for a fact that the last GG1 4938 had cast iron plates. Perhaps its production in 1943 bumped into some material restrictions. Other loco builders also changed from bronze plates to iron around the same time and some that had used sheet brass changed to sheet zinc during WWII.

As other plate collectors will tell you the PRR was very friendly about selling builder's plates from their locomotives, especially steam. I believe the fee was $5.00 per plate; and was the RR's choice. In some cases they even sandblasted the soot off of the plate before sending it.
Although it's not being suggested I get the feeling that many people believe that builder's plates are secret stolen items; and that is far from the truth. Many RR's sold plates, bells, headlights, throttles, etc to those interested, and I knew many collectors that got them from the many scrap yards across the USA.
It sounds like you made a great find ! Isn't the P5a a streamlined one like a GG 1 ?

Kevin K.

And it's a statement I did not make.

I chose my words carefully.

Dave Hamley is 100% correct that the last GG-1 had cast iron plates. I have one of those plates in my collection. It was my understanding that some of the last GG-1 locomotives had cast iron plates due to war restrictions on aluminum. I rarely post anymore as I do not have all of the answers like some that post all the time.