Silly, basic question

[Beatthe9ers]

What is the difference between 33" and 36" wheel sets.  I know, 3"!!

What does the measurement refer to?  The length?  The diameter of the wheel?  The reason I ask is that someone once recommended that I but Intermountain 36" wheels for some passenger cars I have and I am wondering if 36" wheels are appropriate for all types of cars, or if you need different sizes for different things.  Is it just preference?

Parker

[Jake]

The measurement refers to the diameter of the wheel. And I'm not exactly sure about them being appropriate for all cars. (I know they aren't, but I'm not sure which they are appropriate for and which they aren't)

[Yampa Bob]

 Hi Parker
Generally freight cars up to 70 ton will have 33 inch wheels.  100 ton cars will have 36 inch wheels,  a few special 70 ton might also have 36 inch.

Passenger cars 36 inch wheels. 

Bob

[Beatthe9ers]

Thanks.  So if I am replacing wheels on some old box cars I bought, the 33" is the way to go.  Got it.

[Yampa Bob]

When  you put the new wheels on, check the coupler height, you may have to shim down the coupler box or shim between the bolster and the trucks, depending on which way it is off, if any.  The rule I follow is "coupler high shim down the box"  "coupler low shim the bolster", or sometimes I sand down the bottom of floor to raise the coupler.  Just takes some messing with it to get it right, is isn't rocket science. 

Also make sure the knuckles are square with each other, that they are not sagging down.  If couplers have excess vertical slop, one can "cam", or ride over the other in extension or compression, causing decoupling.

I also check coupler height after changing trucks, there are slight variances among various truck classifications, even among manufacturers.

Rebuilding old cars is lots of fun.  I have updated over 50 my friends gave me.  One was a highly detailed Kadee, in MIB  (mint in box)  I'm especially proud of.  A friend bought it for 50 cents at a yard sale.   My favorite coupler is the Kadee 148 Whisker (same as #5 basically)

Bob

[Guilford Guy]

Any Pre-1950's freight equipment should have 33",  passenger 36". Large cars such as autoracks, introduced in the 1960's, or centerbeam and doublestacks should have 36" wheels. Many modern boxcars, and other rail cars have 36" wheelsets.

[Beatthe9ers]

Yeah, I don't mind saying you are way over my head right now.  Pre 1950's?  Doublestacks?  Centerbeams?  No idea what what the last two are or how I would determine the first.  These are a bunch of freight cars I bought off ebay for my 4 year old son in bulk, $20 for 14 cars.  One of them says 'Jell-O' on the side.  Another says 'Kelloggs'.

Adherence to prototype doesn't particularly interest me, I just want to make sure I am not buying something that won't work.  Sound like I am generally safe with either of the two wheels sizes.

[Guilford Guy]

I'd buy all 33" wheels, and if some cars don't seem to ride right, buy some 36" wheels for them.

[Dr EMD]

Steam era wheels have ribs on the back (chilled wheels).

Modern wheels are plain on the back.

Nothing worst then seeing a jumbo hopper with ribbed wheels.

[Yampa Bob]

I would suggest the Kadee #520 - 33 inch metal wheelsets.  They are smooth back and good runners. 

Bob

[Stephen D. Richards]

"Rebuilding old cars is lots of fun.  I have updated over 50 my friends gave me.  One was a highly detailed Kadee, in MIB  (mint in box)  I'm especially proud of.  A friend bought it for 50 cents at a yard sale.   My favorite coupler is the Kadee 148 Whisker (same as #5 basically)"


Same here!  You don't hear much about the #148 Whisker couplers but I use them for just about all rebuilds, replacement, etc. now.    Stephen

[Yampa Bob]

I have lousy eyesight, but can assemble the 148 box by feel, and easy to hang onto while inserting the bolt.   I keep at least 10 packages on hand.

Bob

[SteamGene]

Doesn't the 148 come in bulk packs yet? 
The ribbed wheel was phased out before the transition era began -as I understand the transition era, which would really not begin before 1940, I don't think.  I'm not sure the railroads looked at the total disappearance of the steam locomotive until after World War II.  And then it began gradually - "We'll go diesel for passenger and retain steam for freight," or something like that. 
!950 was sort of a threshold with railroads - before then steam was still in the majority, after 1950 steam began to fade, slowly at first and then rapidly.  Centerbeams and doublestacks are modern cars.  The centerbeam is a flat car with a tall horizonal ridge in the middle.  It's used for transporting finished lumber by and large.  A double stack has a sort of well and the tri-transport (rail, truck, ship) containers fit on it, often one on top of the other. 
(See, I really do know something about today's world!
Gene

[ebtnut]

OK, look here's the basics.  In essence, all "standard" freight cars in service prior to about 1960 had 33" diameter wheels.  Unless you are building contest-level models, don't worry about ribs on the back.  Most all passenger cars, then and now, have 36" diameter wheels.  More modern rolling stock (big covered hoppers, 100-ton coal hoppers, etc.) usually have 36" wheels.  Some modern cars like double-stacks (those that can carry two shipping containers stacked one on top of the other) may have 26" wheels in order to reduce the overall height of the car to clear tight tunnels and bridges.  If you have what look like "typical" cars (40 foot box cars, 40 or 50-foot gons and flats, two-bay coal hoppers) then 33" wheels are what you want.

[Redtail67]

Just a note about wheels with ribs on the back:

While infrequent it was not uncommon to see wheels with ribs on the back well in the 1980's. I also would not doubt that some are still out there on pulpwood and log cars.

Redtail67