Repair broken cap on KS14C Control Board

[DaveThomasPilot]

I've had to remove and re-insert the control board in my KS14C too many times while trying out potential replacement boards.  Every time I removed the board, I had to bend the leads on the 2200 uF aluminum electrolytic capacitor out of the way to access one of the four screws that attach the control board to the wheel's housing.  When the replacement boards wouldn't work, I went back to the original board to make sure something else in the wheel was not causing the problem.  Then back to the replacement board to see if it really was bad.  Then the orignal control board was inserted   Finally, one of the cap leads on the original control board broke.

This is likely a common problem, since there's no way to remove the board without bending the leads and then bending them back when the board is replaced. I decided to document how I repaired it so maybe it will help someone else having the same problem.

I found a replacement cap on Digikey, but I didn't want a place an order for the single $4 part.  I order from them frequently, so I decided I'll wait until I place my next one and meanwhile implement the repair using the broken one.

I don't think all four screws are needed to attach the control board to the housing.  If only three are used, it might not be necessary to bend the leads to remove the board (or at least not as far). 

The remaining lead length on the broken pin was too short for a 90 degree bend, so I soldered header pins in pcb through holes instead of soldereng the cap directly:

 

Then, I soldered the leads of the capacitor to these pins:

I still may have to unsolder the cap to remove the control board next time, but I think that's better than continuing the fatigue the cap leads until they break again.

Also, rather than use what seemed like a silicone glue on the screws that attach the pcb and the motor wire screws, I used blue thread lock. 

The original glue KS used gets in the screw heads and has to be picked out with tweezers before the screws can be remove.  We always used blue thread lock (don't use red!) for all screws when we built RC helicopters. We'd clean each screw with alcohol, then use a toothpick to put a tiny amount of thread lock on the screw threads.  They never came loose, despite the extreme vibration to which they were subjected.