Wheel set size for HO scale freight cars?

[Anonymous]

Hey I've been in and out of the forum lurking for a few months, and I have been slowly getting my feet wet in the world of Model railroading. I have a few rail cars that have plastic wheelsets and want to convert them over to metal. but i don't know what size I am to use on freight cars... I know I've read that freight cars and passenger cars are different sizes, and i want to get the proper size wheel sets.

Thanks,
Chad

[sparkingbolt]

Generally speaking, most freight cars have 33 inch wheelsets. Heavy duty cars will have larger, but for our 40-50 foot cars common to model railroading, 33 is the standard. Dan

[bogp40]

QUOTE: Originally posted by sparkingbolt

Generally speaking, most freight cars have 33 inch wheelsets. Heavy duty cars will have larger, but for our 40-50 foot cars common to model railroading, 33 is the standard. Dan

Much of the newer equipment will use 36" wheels. However there are many of the models- MDC bulkhead flats for one, some centerbeams and heavy duty or depressed flats that can interference problems when the wheels are changed to the larger size. Trimming of the center sill or raising the car w/ bolster washers may even be nec. Check your prototype and experiment to see if the larger wheels will fit and not cause any problems. Remember coupler height will also be affected, but since many Athearn and the like can have low couplers the small change is generally insignificant.
Bob K.

[Anonymous]

Thanks for all the input. I don't really have a time period i'm modeling yet, but i know it' will probably be anywhere in the late 70's thru the mid 90's when conrail was disbanded. I just have some cars that have plastic wheelsets, and wanted to upgrade to metal. Thanks for the suggestions and tips. The reason for the era is because conrail was the only rail company to operate in this area when i was a kid and growing up. now i see CSX, Norfolk n Southern, Union Pacific, BNSF. The latter two i have only seen recently, and have wondered how they made it out here in the great lakes area. Thanks again.

Chad

[Anonymous]

A good rule of thumb:

Up two 77 Ton Capacity - 33" wheels
100 Ton Capacity Cars - 36" wheels
Over 100 Ton Capacity - 38" wheels
Some intermodal cars used 28" wheels for clearance problems, also some of them used 38" and 28" mixed on the articulated stack cars.

I don't know what Athearn is now using for their Covered Hopper cars now; but if you have the older blue box kits you should replace the 33" wheels with 36" wheels, this will also raise the car to the proper height so the couplers will match up with the rest of the cars.

Rick

[Anonymous]

A word of caution.
Beware, not all metal replacement wheel sets have the same axle length.
This is because the dimension between journals(span) among truck manufacturers
varies and model car manufacturers do not use the same truck manufacturer.
The P2K's measure 1.008, IM 1.013, KD 1.018 and the list goes on.
As noted in http://www.nmra.org/beginner/wheelsets.html Reboxx , leading
after market manufacturer sells axle sets that match specific model car manfacturer's
wheelsets to facilitate "drop in conversion".
www.reboxx.com

[Don Gibson]

33'' will do 98% - 99% of your freight cars.
Since most of our car's are made overseas, some are coming with NEM axle's instead of NMRA.

Jaybee makes 33" wheelset's in both NMRA and NEM sizes. I keep spares.