Broken System Controller: Brittle plastic around screw failed

[JC-1]

For the second time, I’ve had the plastic around the retaining screw crack away and the controller pop out. No impacts, no repeat installations or over tightening. The plastic directly below the screw head just crumbled during riding and it popped up. The first System Controller was replaced under warranty. I’ll speak to the bike shop again, but I’m worried it will keep happening. The plastic is very thin below the screw head. I’m in a very hot and sunny climate that probably isn’t kind to low quality plastics. That’s all I can think of

Anyone else had this?

 

[RustyIron]

Yes, sir. I know exactly what you're talking about. I took mine apart when it was new, and the plastic already appeared cracked. I overlooked it at the time and promptly forgot about it. It was another six months before I took it apart again, and by then it was completely broken through.

I didn't have time to screw around with a warranty because I wanted to ride the next day, so I whipped out a solution out of a chunk of aluminum. My intention was after proving the concept, make another that sat more flush. But the first one works fine, so I haven't bothered. Originally I colored it with a black Sharpie, again, planning to color the final one with paint that would be more permanent. Now I'm not concerned about it.

Below are pics of my solution. If you have a lathe, you can knock it out in half an hour. If you don't have a lathe, you can solve the problem with a washer and a button head screw. Like you said, just getting a replacement won't permanently solve the problem.

 

[JC-1]

Neat. Thanks. I don't have access to a lathe but I’ll look into something similar. My friend has a 3D printer. Maybe I can get something plastic made up.

 

[RustyIron]

Neat. Thanks. I don't have access to a lathe but I’ll look into something similar. My friend has a 3D printer. Maybe I can get something plastic made up.

A 3D printed chunk of plastic sounds even better. A couple cylindrical shapes with some bevels seems like child's play to someone who programs that sort of thing.