XRAY - Model racing cars

I only had them popping off once and that was in a hard crash. I'm happy they pop off in a hard crash otherwise the piston would bend or worse.
But you can find some directions to get rid of the problem.

If you are you talking about the ball cup coming of the ball then have a look here: .

If you are talking about the screw working loose than we are talking a different problem that I have never had myself. More to the point I haven't heard comments on that very often which to makes a statement like "surely this is a bad design" a bit harsh in my book... Especially since this is the type of design just about all manufacturors use in one form or another.

Anyway, on to figuring out and solving your problem. Assuming it is the ball working loose from the grub screw the first question is whether you are using the correct length grub screw. When using the threaded balls that require a grub screw in the arm to mount it the first thing to make sure is that the grub screw only sticks out about 2mm. Any longer and it will hit the 3mm allen key you need to screw the ball on. The length of the grub screw inside the arm should be at least 4mm. This means you can use 6mm grub screws. Now when you mount the ball you should not overtighten, but once it is on you do need to tighten it slightly. Normally if you do this it will not work loose as the composite on the arm has a high resistance keeping the ball from turning. In your case this does not seem to work so I recommend for next time that you use a small amount of thread lock. You can even use some thread lock in the hole in the arm.

Thanks for the info..will try the solution out.

I have used a small amount of thread lock on the grub screw and inserted a washer between the hex ball and the composite to try and stop it from messing up the grub screw thread.

Cheers,
S

I had the same problem one weekend. Instead of the setscrew in the are, I now tread a 3mm button head screw through the hex ball and screw this int the arm. I have not had one pop off since doing this and as Joep posted.

I had this problem a couple of times before, basically forget the grub screw,
use a 10mm M3 screw to hold the shocks on the lower wishbone, this way more secure, I have never had a single problem since I started doing this