Spring matters

[Nick_Burman]

Could someone please explain to me why do some (older) Japanese freight cars have ellpitical springs in their bogies instead of the (theoretically) more common coil ones?

 

Cheers NB

[bikkuri bahn]

My understanding is that elliptical springs provide a better ride than coil springs.  That's why it was common on US railroads for caboose trucks to be fitted with the type, rather than coil springs.  Though I suppose that is offset by being more maintenance-intensive.

[marknewton]

They do provide a better ride, but that's also due to them being used in conjunction with swing bolsters, which was typical US practice on cabooses. I can't say I've ever noticed elliptic springs on freight stock. Cna you give some example, Nick? You've got me curious! 

 

Cheers,

 

Mark.

[Nick_Burman]

They do provide a better ride, but that's also due to them being used in conjunction with swing bolsters, which was typical US practice on cabooses. I can't say I've ever noticed elliptic springs on freight stock. Cna you give some example, Nick? You've got me curious! 

 

Cheers,

 

Mark.

 

Mark, for instance the TaKi9900 tank cars (Tomix HO - http://www.1999.co.jp/eng/10102659), TaKi1900 cement tanks (http://www.1999.co.jp/eng/10064259), Hoki800 ballast hoppers (http://www.1999.co.jp/eng/10051741), WaKi1000 express boxcar (http://www.1999.co.jp/eng/10014059, ToKi15000 gondola (http://www.1999.co.jp/eng/10003548)... the list is endless, a look in Hobbysearch wil yeld several examples...

 

 

Cheers NB

[bikkuri bahn]

Prototype pics taken today at site of former JNR Mikasa Station, Hokkaido.  Hoki 700 and bogie.

[marknewton]

Mark, for instance the TaKi9900 tank cars, TaKi1900 cement tanks...

 

Nick, how embarrassing! I have examples of both these Tomix models, and I've never noticed that they had elliptic springs. Looking at the TaKi1900 kits, I see they have the option of fitting either elliptic or helical springs during assembly.

 

I can understand the express boxcar needing elliptic springs for better ride quality, but I doubt it would be necessary on other freight vehicles such as the hoppers, etc. So there must have been another reason JNR favoured them.

 

Cheers,

 

Mark.

[marknewton]

Prototype pics taken today at site of former JNR Mikasa Station, Hokkaido.  Hoki 700 and bogie.

 

Very interesting, BB. They appear to be compound springs as well.

 

Cheers,

 

Mark.