XRAY - Model racing cars

Anyone got any tips for setting up the diff on the x12? I can never get it feeling really smooth

Ean

make sure everything is really clean, sand the diff plates, ceramic balls and thrust, minimal grease too much just attracts the dust and grit, break the diff in properly then adjust to the final tightness. This gives me a really good diff which lasts many runs

What Niall said.

Sand the rings with sandpaper

Don't use too much grease

Be patient with the break-in process

what is the break in process exactly?

Get yourself a glass or plastic cup and clean it out with brake cleaner, then put all your diff parts in there and hold your hand over as much of opening as you can while allowing room to get the nozzle of the brake clean in there and give it a few good shots then swirl it all around a bunch. Make sure everything is plenty clean. Then have a nice thick towel ready and pour out most of the brake clean, but not the parts. Give it another quick shot with the brake clean and then pour it all out (including any liquid/brake clean) onto stacked up paper towel.

So far none of that is special ... but, the thing I've found that works best for me ... is at this point DO NOT attempt to dry or 'rub down' the parts to clean/dry them. I've always found that this picks up more small particles from whatever you are using and makes the parts rough again.

Take the d-rings and give them a light sand with 1000 grit on each side and re-assemble like normal. When it comes to putting the diff balls in the spur, make sure not to rub them or drag them on the paper towel.

And as others said - use minimal grease.

The break-in process, how I understand it, is just simply the initial couple hundred rotations the diff goes through to settle everything in place, distribute the grease and to create the little lines in the d-plate you see when you take it apart. I speed this up by slightly (SLIGHTLY) over-tightening the diff nut and turn it by hand 20/30 times. At first it should be ever so slightly 'rough' feeling ... then after this break in it should feel like 'butter' as some would say.

When I was first learning about how to prepare a ball diff I ended up re-building the one in my 12th scale 4 or 5 times before I got a good one. Now it is easy and quick. Can do the whole thing in 3 or 4 minutes.

Luke

Cool, thanks for the info ill give it a go .