Did MT Axle Lengths Change at Some Point?

[Chris333]

Scribing straight lines.

[peteski]

The mind reels trying to think of possible non-measuring activities that could be done with digital calipers...

Hehehehe . . .
Maybe I exaggerated a little.    The other main use is to use the pointed jaw tip to scribe lines in styrene, or metal some distance from the edge of the sheet  (after dialing some dimension in on it).  It is really handy for that.

[Rossford Yard]

N scale axle length for each mfg has always confused me.  I have bought many metal wheels, but haven't installed them as of yet, mostly for fear, LOL.  I found this list on sbs4dcc site.  Does anyone know if it is still accurate for at least most cars?

 
Arnold-Rapido - 0.573 in

Athearn - 0.540 in

Atlas - 0.553 in

Bachmann - 0.560 in

BMLA - 0.540 in

Con-Cor - 0.563 in

Deluxe Innovations - 0.553 in

Exactrail - 0.540 in

Fox Valley Models- 0.540 in

Intermountain - 0.553 in

Kato - 0.563 in

Lima - 0.549 in

Micro-Trains - 0.540 in

Model Power - 0.567 in

Roundhouse - 0.549 in

Rivarossi - 0.549 in

Walthers - 0.545 in

If accurate, now all I need is a quick list of cars that would have either 33" wheels vs. 36" wheels?  (modern era)

[reinhardtjh]

Atlas - 0.553 in

Bryan mentions in the other wheel thread

The newer Atlas models use .540” axles — the ex-BLMA cars, the new Master tooling (PS-1, the TOFCs, the coil car). All the models developed prior to the PS-1 run on earlier Atlas trucks that use the longer axles.

So the 0.553 is only for older Atlas cars.

My current wheel axle length document has this (Geared towards FVM wheelsets). It also need some updating now:

Anyone else who is contemplating changing out plastic wheels for Fox Valley metal ones may find the following axle length info for FREIGHT cars useful:
 
To determine if a freight car ( in my modeling era ) needs 33" or 36" wheels, add the load limit to the light weight. If the total is at or under 220,000, it gets 33" wheels. If it's over 220,000 but at or less than 263,000, it gets 36" wheels. 
 
FVM-3301 33" Wheel with .540" axle - Micro-Trains, Athearn
FVM-3302 33" Wheel with .553" axle - Atlas*, Older Bachmann, Bowser, Intermountain, Kato, Red Caboose
FVM-3303 33" Wheel with .563" axle - Keystone Details 2DP5

FVM-3310 33" Wide Wheel with .540" axle - Micro-Trains, Athearn
FVM-3311 33" Wide Wheel with .553" axle - Atlas*, Older Bachmann, Bowser, Intermountain, Kato, Red Caboose


Bowser GLa wheel replacement       - FVM-3302 33" Wheel with .553" axle


36" Wheels
FVM-3601 36" Wheel with .540" axle - Micro-Trains, Athearn
FVM-3602 36" Wheel with .553" axle - Atlas*, Older Bachmann, Bowser, Intermountain, Kato, Red Caboose
FVM-3603 36" Wheel with .563" axle - Keystone Details 2DP5, Atlas passenger, Rivarossi passenger
FVM-3604 36" Wheel with .526” axle - Rapido passenger cars.
FVM-3605 36" Wheel with .576” axle - Atlas modern

FVM-3610 36" Wide Wheel with .540" axle - Micro-Trains, Athearn
FVM-3611 36" Wide Wheel with .553" axle - Atlas*, Older Bachmann, Bowser, Intermountain, Kato, Red Caboose
FVM-3612 36" Wide Wheel with .576” axle - Atlas modern

*Some Atlas cars will require Atlas metal wheel sets  for a proper fit, most will be fine with the Fox Valley .553's. 

MT-1017/1018            - FVM-3301 33" Wheel with .540" axle (36” but have to trim/bend brake hanger)
MT heavyweight trucks         - FVM-3601 36" Wheel with .540" axle
Keystone Details PRR trucks 2DP5    - FVM-3603 36" Wheel with .563" axle


Notes:
First 2 digits = Wheel Size
Last 2 digits = Axle Length
01 = .540" Axle - Fits MT Trucks
02 = .553" Axle - Fits InterMountain Trucks, Some Atlas
03 = .563" Axle - Fits Some Atlas, Con Cor , Bachmann

[bbussey]

N scale axle length for each mfg has always confused me.  I have bought many metal wheels, but haven't installed them as of yet, mostly for fear, LOL.  I found this list on sbs4dcc site.  Does anyone know if it is still accurate for at least most cars?

I would recommend going by the truck manufacturer, rather than the model manufacturer.  Certain truck frames are used across a large swatch of manufacturers.  As an example, the T-Frame truck used by Bachmann currently on their higher-end models such as the USRA twin hopper and the two tank cars is actually made by Bowser and utilized on some Bowser caboose releases (and it's .540" if I remember correctly).  I don't know who makes the Andrews trucks for the Bachmann high-end Northeastern caboose.

Affa is/was a contractor in China and tooled the original BLMA ASF 70-ton and 100-ton truck frames.  They've also tooled the Barber S-2A truck frame used on the Atlas PS-1 and the friction-bearing caboose leafspring truck frame used on the FVM wagontop caboose, as well as variants on the BLMA ASF trucks frames that have an MTL-style raised offset-hole bolster so they can be used on models tooled for MTL trucks (such as many of the FVM models and all of the TWX models).

The numerous 50-ton, 70-ton and 100-ton friction-bearing and roller-bearing truck frames common to Atlas models that take .553" axles originally were tooled in New Jersey.  They've probably been retooled since then in China, as the original tooling dates back to at least the 1980s.  Subsequent frames such as the Andrews (on the USRA boxcars) and the National C-1 (on the Hart hoppers), as well as the roller-bearing and friction-bearing leafspring caboose trucks match the older axle requirements, since Atlas has had a plastic wheelset with .553" points for decades.  And that is the tell regarding Atlas trucks — Any Atlas truck currently equipped with metal wheels most likely is .540", while any equipped with the dark brown plastic wheels is .553".

Rapido's trucks (not Arnold) are Barber S-1 on the GARE meat reefer if I remember correctly, and the axle length is at least .553 if not more.  I don't remember what the passenger trucks are, but their passenger wheels look good and work well so there isn't any need to replace them.

Kato if I remember correctly has lengths longer than .553".  I don't recall the truck style on the cement hopper.  And with the passenger equipment trucks and wheels, same situation as with Rapido applies.

All Micro-Trains is .540".  If there is a difference, the truck frame needs to be flexed to be put back in spec.

The vintage early-generation equipment (RivaRossi, Roco, AHM, Lima, vintage-Atlas, vintage-Bachmann, Minitrix, Model Power, Life-Like, etcetera) with trucks equipped with Arnold-Rapido couplers and metal clips to hold in the spring are all over the place, but tend to be longer than .553 because the trucks are out of scale (too wide).  Even more so with Arnold-Rapido freight trucks and Con-Cor freight trucks.

Bowser's PRR Crown trucks, I'm not sure but I think they are .553".

FVM's multiple axle lengths are documented above, and their caboose truck is .540".  The non-wagontop-caboose equipment uses either Affa or MTL truck frames.  ESM wheels currently are .540" only, and their ASF trucks are .540".  All their equipment not using their trucks used MTL and Affa frames.

Everyone else for the most part utilizes one of the existing truck frames made by MTL or Affa on their models.

You have to look at the manufacturer of the trucks, not the model manufacturer.  We always do, especially in regard to the ESM craftsman kit line, because we try to get as close to prototype as we can.  There are many prototypical truck styles available in N.  Fortunately, most of them take .540" axles.

[Mark5]

The Atlas 20,700 tank cars apparently have a weirdo axle length, not sure if Atlas is still using them on newer runs (0.568" or 14.44mm).

https://www.therailwire.net/forum/index.php?topic=41516.msg518724#msg518724

I wish everyone would just settle on a standard  (0.540" would be my vote).

Mark

[Maletrain]

I have some older Bachmann cars that need axles around 0.568" and even 0.572".  For some reason, Fox Valley used to sell 0.578", so I expect that length was used by somebody at some time. 

Several years ago, I remember ordering Fox Valley wheels of a particular length, and getting a significantly different length.  I contacted Matt, and he  apparently went through a LOT of his stock looking for axles that were at least at the end of the spec I ordered (rather than larger), and those worked.  So, I'll say again, thanks for making the effort to make it right for me.  But, my point in relating this is that I then noticed that Fox Valley added another axle length to their inventory that was what I had actually received the first time when I ordered a different size.  So, I really don't know if that was just a screwup in identifying the batches, or if an unintended axle length somehow got manufactured, and was later identified and put up for sale as such.

[bbussey]

The Atlas 20,700 tank cars apparently have a weirdo axle length, not sure if Atlas is still using them on newer runs (0.568" or 14.44mm).

https://www.therailwire.net/forum/index.php?topic=41516.msg518724#msg518724

I wish everyone would just settle on a standard  (0.540" would be my vote).

Mark

Everything new (other than the Rapido Barber S-1) is being tooled to accept .540" axle length.

[jereising]

This thread needs to be highlighted - a ton of good information there.

[mmagliaro]

.553 FVM wheelsets for older Atlas cars, yes, and also... Atlas Rivarossi steam loco tenders, I recently found out.  And they look and work (electrically) much better than the original tender wheelsets, which oxidize and corrode very quickly.