I popped in to check in on Himself and get the low down on the Garratt test running session the other day.
He was in the process of swapping round motors on the power units to confirm his suspicions that one was running much slower (or faster) that the other, and that is was nothing to do with the chassis.
We do have some spare Mashima motors in stock - and does appear possible to order replacements online - the issue is more that having loctite'd the worm gear onto the shaft of the slow running motor he has yet to find a method of removing it so it can be transferred to a replacement.
So the search is on for a source of additional worm gears.
We'll get there, I'm sure....
I also noticed on the workbench the first signs of something happening towards our fifth Garratt, number 130.
The final batch of Backwoods Kits came with spoked wheels, rather than the solid ones that the real locomotives had, so Himself's plan for that is to fill the holes between the spokes with Millput.
But the time it's painted black and hidden behind the frames and those huge balance weights no one will know the difference.