TT scale trains and models

Ok. Than just the joint between the frames and the back of the frame where the motor and truck mounts

Murad wrote:Ok. Than just the joint between the frames and the back of the frame where the motor and truck mounts

That I can do. I have a bit of a fear of disassembling the running gear of model steam locomotives after I took apart an old Varney 4-6-0, and ended up bending the gear while it was off.

Here we are:

Does anyone have a suggestion for what to use to make a u-joint for the front engine in the HP Challenger?

The FIRST question is how will you mount/support the worm and shaft on the front engine?

I would suggest a brass |__| (i.e. "U") bracket spanning the drive gear, and supporting the worm shaft with bearings and thrust washers on each side.

With the worm shaft extending to the rear, 2 universals joined with a sliding shaft should work well. The NWSL site has all the parts; drive shaft components from a diesel could also be used.

I have decided that I will use a spring for the u-joint on my Challenger as it will provide the needed flexibility, as well as enough "back force" to help keep the ball joint in it's seat as well.

Here is my articulated construction from 1982-3.
The ball joint is very short, just about 10 mm, all wheels are driven with individual worm gears. Both frames can turn, the second one just a few degrees. The motor sits on the second frame and turns together with it.