@John Cutler said:
I am still not happy with the slow-running performance of the Terrier.
It tends to stutter at certain places in the yard .
I think that often only 3 wheels are in contact with the track and picking up current due to the bumps and the lack of any slop (or springing or compensation) in the axles.
I tried filing the keeper plate to try to allow the centre axle to fall slightly (it is raised above the other two).
This seems to have failed; I suspect the mazak holding the bearings needs to be slightly filed away too but this scares me.
Has anyone managed to do this?
I guess another possibility is to introduce vertical slop on all the wheels.
Bear in mind that without some form of springing or compensation, “slop” just generally results in the body settling in the lowest position and you have a de factor rigid chassis again.
Yes, a bit of slop can help on a centre axle, but you really need to be able to hold the axle at “mid-point” in some way so it can move up and down. An axle being able to drop only may be of use if you have a pronounced dip over a short (sub-wheelbase) length, but the improvement is marginal.
What problems have you identified in the track? A compressible substrate can cause issues – I know, my test-track sits on Exactoscale expanded foam, so should have vulnerabilities in the same way. But the real problem might be a vertical kink at a rail joint, or similar. No matter what it is laid on, an unbroken length of bullhead or flatbottom rail should have a dead straight flat top. Unless the baseboard has blown over in a carpark and the kerbstone has put a vertical kink in the rails across all running lines – DAMHIK!
I’m interested to hear more to help diagnose this. Would a picture of the troublesome track be possible?