This page contains locomotive parts suitable for 55n3. It is not a complete listing and will change as more resources are found.
Drivers, Gearboxes and Motors
Objects aren't "N, HO..S, O , etc. SCALE", an object is what it "MEASURES".
(Click Images to Enlarge)
Scale55 has the largest available quartered drivers in three foot gauge. Locomotives can't be built without drivers.
The Mantua/Tyco Ten-Wheeler
The Mantua/Tyco Ten Wheeler is really a 64n3.5 locomotive and not HO. It matches a SP 3 footer in Scale64. They can be found at trains shows.
By utilizing the back two drive slots a small 4-4-0 can be developed. The chassis will except up to 19mm diameter drivers without boiler modifications. Shorten the frame and add a two wheel pilot and a mogul can be developed.
Bowser's HO Pennsy I-10 Decopod Frame matches the wheel spacings for a 2-8-0 and 4-4-0.
If anyone runs across anything useful in 55n3 please e-mail me and we can add it to the page.
Roundhouse HO Locomotives
Roundhouse HO locomotives lend themselves to conversion to small mining and logging locos
Shapeways and Other 3d Printers
3d printing has opened up a new world of available resources.
Here is an S Scale cab for the Bachmann Mogul which makes variants of the mogul possible.
I constructed this Sn3.5 cab in 3d and had Shapeways print the cab. The sky is the limit.