I am in the process to change the plastics wheels for metal ones. I have Athearn and Walthers freight cars and also IHC passengers. Is there a place where I can find the dimension ( 28, 33 or 36" ) for which car (3-level auto-carriers, box, tank, hopper covered or not, … )?
A good rule of thumb is that HO freight cars generally take 33" wheels and passenger cars take 36" wheels.
However, freight cars over a certain weight capacity (I think 70 tons, but not sure) take the larger wheels. Also, in real life, there are other exceptions, such as the double stack container cars that take a smaller wheel due to height restrictions in tunnels, but I don’t have all that info in front of me right now. I don’t own any container cars, so I can’t say for sure about what size model wheels you’ll need.
Here are some general rules:
- Most passenger cars use 36" wheels
- Freight cars that car under 70 ton capacity usually get 33" wheels(most box cars for example)
- Over 70 tons - 36" wheels(like those 3 bay covered hoppers)
- Some TTX flats and many auto racks use 28" wheels
- Doublestack ‘well’ cars may have a mix of 33" and 36" wheels
Of course there are always exceptions. And on our models, they may be designed to use a different wheel than the prototype. IIRC, the Walthers enclosed auto carriers have 33" wheels, and I suspect you may have problems installing 28" wheels(like coupler height issues).
Jim
I tried to change the wheels on my IHC to 36" but they dont fit because of the shoe brakes. As for the height issue, I am prepare to change the coupler of my 2 auto carriers.
Since you’re most likely going to need both sizes of wheels, buy a pack of each. When you remove the old wheelsets from the trucks, you can match the size by holding the axle ends together and checking them, thru a magnifier if necessary. You want the same size at the wheel tred. The flanges from different manufacturer’s wheelsets probably won’t be the same.
And yes, DEFINATELY check the coupler height and clearance after the wheel changes and adjust as needed.
There are two ways to get around this.
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Carefully shave off some of the offending material so they fit.
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On lightweight cars, whack off the shoe detail entirely, and say the cars have Budd disc brakes. The disc brakes fit entirely behind the wheel, no visible parts from outside. (When air testing cars so equipped in 1:1 scale, you have to bend around and get a good look under there to see if they are actually functioning.)
Regardless of what size your research shows what railroads used our model industry tends to supply what’s most economical for them. You are wisest to match whatever size they give you.
For most it’s 33" and 36" for Passenger. For IHC it’s 31.5" according to my calipers.[:O]
Wheel dimensions can be very frustrating. Just today, I am waiting for an email reply from NWSL about a question I have concerning the conversion into the decimal form for correct axle length.
I have replaced all my IHC six wheel passenger cars with their metal ones. I know they are not scale exact, but I like them. I even bought some IHC’s all metal sprung trucks for them, but I did not like how high they sat.
IHC’s metal trucks solve a lot of problems for their Passenger cars, and are good rollers. 1. they get rid of plastic trucks 2. allow body mounted couplers 3. improve tracking. 4. offer electrical pickup for interior lighting.
80’ - 86’ cars go best with 36" - 44"curves, but that’s for your next improvement, and is true of all long cars. I like to add weight to get 6 oz - 6.5 oz total to mix with other cars, and secure the mounting better with metal screws.