Progress HAS been made! This is a family photo of the gang - so far.
From back to front on the left side are:
1) The Kong axle with the modified rear wheels. I got my order of tires, so I can actually put tires on everything now.
2) The modified Frankendiff, still haven't shortened the axles though.
3) The prototype of the front axle - it still needs work. It's only got one wheel mounted because I don't have any more 5x9x3mm ball bearings. They are on order, should be here this week?
4) The other front wheel, with hub cover just laying in place.
On the right side are the next donor diff, and the left-overs from the donor front axle.
I've redesigned the rear axle's front and rear halves, making some minor tweaks.
1) I moved all the case mounting screw locations away from the axle bore, They were close enough to the bore that when the screws were threaded in, the inner wall would expand into the axle bore and bind on the axle.
2) I changed the angled transition to allow a convenient spot to bolt the springs to the axle.
3) I took the donor diff apart to see if the binding that I feel was coming from the spider gears - it was/is. There's no clearance in the gears. In fact if the screws that hold the spider gears cover in place are tightened down you can completely lock-up the differential. When I shorten the axles I'll take a little off the back side of the gears. That should make things work a little better.
The front axle needs a little help yet - it's 10mm too narrow. When I initially designed the front axle the plan was to use the steering arms, spindles and king-pins from the donor axle, which measured 205mm outside to outside. I need 175mm-ish, so I had to take 30mm out of the axle. The donor axle had spring perches that are spaced 80mm apart, which is right where I need them, but I need to lose 30mm somewhere. So I played with the design a while. This looked kinda OK on screen, so I printed it out. When I started to install the spindle assembly into the axle the spindle would flop around in the steering arm, they allowed PLENTY of clearance in this one Clarence! So, I am NOT going to use the original steering arms. While designing the new arms I came up with the idea of changing the front wheel offset by 5mm, to tuck the steering knuckle into the back of the wheel - so I did that too. And that my friends is why the front axle is 10mm too narrow. It's a simple fix and the axle only takes about 1/2 hour to print - just forgot about re-printing it.
Unfortunately the "Bag of Misfit Parts" continues to grow.
Don