openinverter forum

Hey everyone, currently working on the issue of getting power from the motor to the wheels. I'm currently weighing the options of:

1. Lathing down the Tesla input stub, machining an adapter plate, and welding the two together. The issue with this is I'm not sure what alloy the Tesla stubs are made of, and what heat treating it has undergone. I would take this part to a professional welder who would have more knowledge on how to approach this than me, but I don't even know what alloy to machine the adapter plate out of. This would be very similar to what Jon Volk did as pictured. The benefit is I would be able to use stock axels.

2. Machining an entire adapter plate from scratch. It looks like the Tesla stubs are 29 spline, 31.5mm OD 29mm ID 30 degree pressure angle. This would probably be measurably more expensive, and I'm worried about the splines fitting correctly after machining.

3. Custom axles. In this case I would get axels made that are thicker, and get the Tesla "tripod" CV on the inside of the half shafts.

What do you guys think the best route is (while hopefully keeping it cheap)?

This usually depends on how things fit together in the vehicle.

If you have a bit of a gap between vehicle axles and the new axle stubs (and all are bolt up style) you can machine up a concentric adapter plate to take up the gap and bolt the 2 together.

There are companies that make Tesla stubs to 100 & 108mm CV joints.

A hybrid axle of the vehicle outer CV and the engine swap inner cv means less futzing with stuff. There are a few custom axle companies listed in the forum. You can send a bubble gum welded axle as your sample as long as the length and splines are correct.

You might be able to go the machined down inner stub axles to what flange you need. This requires axles to be to proper length or close. Machining+welding+machining concentric+heat treatment. If you made things like this for a living it's probably cheaper if you count your time and less hassle just to get custom shafts made up.

Assuming the Tesla axles will need to be shorter, you could check if there's enough material to machine the appropriate splines to mate to the outer rzeppa joints on the car. Then you can send your shafts and the rzeppa star to Dutchman Axles in the USA, where they will cut down and machine the axles. Pretty reasonable prices, too.

What vehicle/axles are you trying to adapt to?
German? Ie a bolt on cv joint?

machining down and press fitting a flange made from chromoly and tig welding is fine, and done often.
matter of finding a shop that welds chromoly. it’s a bit of a process to do it correctly

But Tesla stub flanges to exist for 108mm (930) cv joints.

I’m adapting E30 axels. Not 100% sure if it’s 108mm but haven’t done the research to verify because I don’t like the price tag on this option. I feel like I can do better than $500-$1200. Right now I’m thinking of machining an adapter plate that inserts into the Tesla stub itself. Pretty tight fit with my 3D printer after 6 iterations. I will upload an .stl if it works. Thanks for the tip on chromoly!