Big Rock The slipper clutch is always getting loose


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Arrma RC's
  1. Granite
My black plastic nut held for a long time, but I recently wanted some slipper adjustments and adjusted it a few times. Now it doesn't hold. New one on the way. Planning on setting it once then never touching it again.


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Woking, UK
Arrma RC's
  1. BigRock 4x4
  2. Kraton EXB
  3. Notorious
  4. Senton 3s
There are 2 versions of the black plastic nut, the first had a brass insert (useless) and still required threadlock, the latest one is totally plastic and seems to work well when used right - no threadlock in either my BRCC or Senton and they seem to stay adjusted as set.

However - Arrma still apply threadlock from the factory which messes things up. It means that the first time you move it you have to do a complete clean and reassemble otherwise it will keep slipping. Worst case it can cause the threads in the aluminium to strip on disassembly if you get unlucky.
Unscrew very gently the first time working back and forth if necessary, don't try to force the aluminium to cut through the threadlock, if necessary soak in acetone or de-bonder to soften the threadlock (heat not an option with the plastic in there!)
Once you get the bolt out you will see that the threads are all gummed up - this means that when you screw back into the black plastic the bolt threads (or lack thereof) don't bite into the plastic and don't grip.
The solution is to clean the threads thoroughly before reassembly, I have found the simplest way is a soak in acetone overnight then hold in a paper towel and turn to remove anything left.
After this I have found that the black plastic bit is ok to reuse.