HO Freight Car Wheels

[Anonymous]

Recently I stopped at the local hobby shop to buy some replacement wheels. But HO wheels come in 33 inch and 35 inch. I had never thought of this issue before.

What size would I need for Athearn, MDC, Bowser freight car models when replacing factory supplied wheels?

Many thanks in advance for sugestions and recommendations.

[BR60103]

Most "normal" freight cars use 33" wheels. The larger wheels are used for extra heavy cars.
Take a standard box car and assume that is 33". Compare the wheel size to any other car that you think might have a larger wheel. Some cars may have smaller wheels.
Sometimes you can use a larger wheel to raise a car to get the coupling to the right height.
Passenger cars usually have 36" wheels.
--David

[dknelson]

it is a bit more complex than that. Some very heavy cars now have 38 inch wheels and increasingly so many cars are high capacity that it might be that 36" is closer to normal than 33".
Also be aware that some intermodel or autorack flats have wheels smaller than 33"
Dave Nelson

[dknelson]

it is a bit more complex than that. Some very heavy cars now have 38 inch wheels and increasingly so many cars are high capacity that it might be that 36" is closer to normal than 33".
Also be aware that some intermodel or autorack flats have wheels smaller than 33"
Dave Nelson

[Anonymous]

Try this article by MR
http://www.trains.com/Content/Dynamic/Articles/000/000/002/197xvpbs.asp

[Anonymous]

i got into the wheel replacement to help keep the track cleaner. it is a known fact that metal wheels stay cleaner longer than plastic. all the rtr cars come withmetal wheels but size can be confusing. generally they are 33" or 36". nobody is going to measure your wheels to see if they are correct so stay with just two sizes.

[Anonymous]

You are correct Bob with one minor exception. The Walthers Autorack cars have a smaller diameter wheel. I think that the wheels provided with the ready to run cars are made out of metal, but the older kits came with plastic wheels.

[Anonymous]

i had this problem too. I changed the wheels on a baby hi cube and the couplers where to low . I had put 33" wheels (metal) so I changed them to36" and the worked .
use the coupler gauge for right size.
ew

[nfmisso]

In addition to fine article Charles recommends, as noted in the article metal wheels made by different companies have different axle lengths. I measured P2K 36" wheels at 1.008", Intermountain at 1.013" and Kadee at 1.018". The Kadee's worked great in my Walther's coil cars, the P2K's just fell out. My McKeon 100T hoppers needed the P2K's, with Kadee the wheels would not turn at all, and the IM's had lots of drag.

If you want to keep the same geometry as you have now, measure what you take out, and replace with the same diameter and axle length.

Note: Athearn (Blue Box) uses 36" wheels almost exclusively, even though on most of the cars, this not prototypical. With 36" wheels, Kadee #5 line up with coupler guage correctly. With prototypical 33" wheels, you either have to put washers between the frame and the truck (cheap #4 from the hardware store seem to be correct), or go with a #27, #37 or #47 coupler.

Now to further confuse you, there are different treadwidths. NMRA RP25 is .110", Proto87 (fine scale) is .064", and there is an intermediate width of .088". I just had my first experience with .088" tread width wheels on Athearn Genesis 70ton ASF ride control roller bearing trucks. They work great. The trucks are about the same prices as other premium trucks from P2K, IM, Kato or Kadee. I put them under a pair of older (mid 1960s) freight cars I have.

Nigel