spring has finally sprung and i had a chance to beat on my Ursa with some new beefed up parts to the driveline.
I'm running zxcvbn CV joints now. i'm noticing stress cracks on all the 2mm bolt hardware around the new designed Axles( vertical cracks) from the hardware pulling the top and bottom axle case together. i think the axle wall around the 2mm hardware needs to be beefed up 1-2mm to compensate i'm using PLA. i noticed the same cracks on another Ursa truck that hasn't been run much so i think the cracks formed with the truck just sitting on the shelf over time. the parts have not failed yet but the cracks indicate not enough material to take up the stresses.
the new CVs work very well on the ursa truck. i have not tried the new Ball diff design that zxcvbn came up with.