still need loctite

I thought that maybe with the new set screw, I could get it tight enough that it would not come loose.  After playing with the pendulum tonight, I realized the set screw still gets loose after a lot of fast back and forth motion.  Once I have decided that I have the best set screw I am going to find, I will add some loctite to make it stay tight.  The new screw is still way easier to tighten, if nothing else.  I am also pretty sure I could loosen it after using loctite if I need to.

I also found a very minor bug in my speed calculation for the pendulum.  After sitting still for several seconds, one of my counters rolled over and looked like a sudden burst of speed.  The cart would shimmy a little bit, then return to a still position.  The fix was pretty simple – I thought I had already done it, actually.

2 Responses to “still need loctite”

  1. Lynn Johnson Says:

    Does your motor shaft have a flat or is it round? With a flat you should be able to make a modest setscrew work without all the hassles. Round shafts are good for things like volume control pots. Flats or keys are much better when you need to transfer significant torque and power.

  2. Bruce Ammons Says:

    The motor shaft does have a flat, but it wasn’t enough. I still think the shim foil affected the tightness of the set screw, and it loosened slightly during high acceleration rates while reversing directions. It could also be that the hole for the set screw is slightly worn. I just know using loctite fixes the problem and it doesn’t come loose any more.