Kadee Couplers: What's the writing on the sides of the wheels represent?

Model Railroader General Discussion (Model Railroader)
1

Hi Guys,
I bought 11 packages of Kadee metal wheelsets at a train show this afternoon and when I got home I noticed that the outside of the wheels are not smooth. They have small raised writing on the sides of the wheels which is too small for me to read. Does anyone know the significance of this writing.

I know that “ridged” back wheels were outlawed at some point early in the 20th century and the protoype wheels became “smooth-backed”. However, I’m hoping that the writing on the outside of the wheels didn’t go away early on too. I’m modeling 1959 and hope the wheels with the writing on the sides is prototypical for that era.

Thanks in advance for any help.
Mondo

2

Couplers, writing on wheels? Couplers don’t have wheels. What are you talking about???

3

Sorry, I messed up my original posting. I meant to say Kadee metal “wheelsets”. I editted my posting and fixed it.

Mondo

4

It says ASSOCIATION OF MANUFACTURERS OF CHILLED CAR WHEELS AAR 1940. I’m not sure when the ridged-back wheels were banned, but I think it was around 1930.
Drat, that’s some small writing!

5

Thanks for the input. Do you happen to know when the writing on the sides of the wheels was eliminated or did Kadee just stop making them with the writing because it is easier to make them smooth on the outside?

Thanks,
Mondo

6

I’m guessing it all depended who was making the wheels. It seems to strike me as being some kind of foundry data. Props to lonewoof for actually going to all the trouble to read the tiny letters on the freight car wheels.

7

I’m still hoping that someone can tell me when the writing on the sides of the wheels ended.

Thanks,
Mondo

8

Wheels with ridged backs were made of chilled cast iron. The tread was rapidly chilled during manfacture to harden the metal to improve wearing, while the centre was annealed to make it softer, allowing the wheel to better absorb shocks without cracking. The ridges, or spiral fins, were to help dissipate heat that would otherwise soften the tread. I don’t have a date for the outlawing of chilled wheels, but an article in the 1940 Car Builder’s Cyclopedia states that at the time, 82% of freight cars in service had chilled wheels. So I doubt that they were outlawed in 1930. The lettering cast into the wheels was to indicate that they were made to the specifications of the Association of Manufacturers of Chilled Car Wheels.

Steel wheels had flat backs, as they were less sensitive to heat buildup. I’m taking an educated guess here, but I suspect the reason you don’t see them with lettering is that they are forged, as opposed to cast.

Hope this helps,

Mark.