Prepping diff rings
 

So the time has come to renew my madrat's diff. I have all new parts, but i've read numerous times that it's better the prep the diff rings a little by sanding them.

Now, I have some 800 and 1200 grit sand paper, and my question is, how do I do this? How long do I need to sand each side, in what motion, and when do I know that they're ready?

i use a diff half to hold the diff ring and sand on 800 grit using light oil as a lube;)
untill surface is matt and smooth then finish on 1200till it looks almost polished, dont go mad sanding.

Like above using some sandpaper and a old diff half

Or wait and rapid rc will have some pree done :)

I found the stock rings to be too soft of metal. I used T4 rings with a shim and they last way longer.

1. Use the 800 only, the rings need to have some "grit" feel about them. You actually want the ring to grip the ball not skid over it.

2. I go in a circular motion trying to apply equal pressure across the ring.

3. You will see that the finish becomes consistant, no original smooth finish. Thats when you know your done and they ready.

Note - I spend a little more $$ and buy the B-fast kit for the SX10 (US version of the car) I get the complete kit with carbide balls and thrust set.

Take a look at 3mins 30 secs in