K-27 Chassis Suspension Springs

[armorsmith]

Bachmann, et al,

Does anyone know the outside diameter of the main chassis springs? I am going to, one way or another, install heavier spring rate springs in the #4 driver to reduce the butt sag in my K27. There are several threads on forums that elude to the much improved operational characteristics of the locomotive after doing such a replacement.

For the Bachmann, I might push my luck and ask for the design data for the spring ie. outside diameter, wire diameter, material, free length and spring rate. With this information I would freely be able to order an assortment of springs and find the one that suits my needs best.

Thanks in advance for any assistance.

Bob C.

[MAELLIS]

I also have noticed the "butt sagging" on my K27s. I changed out the springs on the trailing axle with stronger ones that I think came from an Accucraft C-19 tender.

This has improved the look of the locomotive from the side and I think she runs better.


Regards from Norway

[armorsmith]

MAELLIS
This question was asked in preparation for a major overhaul of some chassis components and the electronics, adding battery operation, radio control, and a sound card. My goal at the outset was to make these upgrades without removing the original Bachmann electronics. I have been doing a build thread on the Large Scale Central forum located here :  http://www.largescalecentral.com/forums/topic/22079/major-k27-overhaul . I have also added an aftermarket drive modification to bring the locomotive back closer to prototype speeds at full throttle.
Thank you for your suggestion. I was not able to acquire the springs you thought you used, but similar were acquired and provided good results. I am  not quite complete, but getting near the 'end of the tunnel' so to speak.
Bob C.