The other shoe finally dropped

Several years ago the kitchen slideout started making a terrible rackety-clankity noise when going in or out.  At the time, I was sure the whole slide was going to end up in the street but it turned out to be a small problem that was very difficult to fix.

My mechanical slides are driven by a 12v dc motor through a gear train to a pinwheel shaft with teeth that engage cogs on the two rams.  To keep the whole thing from drifting while traveling or even when parked and extended, there is a permanent magnet and friction disk attached to the back end of the motor's drive shaft.  Very simple arrangement. This brake is wound with an electromagnet winding that activates with the motor to cancel the magnetic field of the permanent magnet so the motor shaft can turn freely.  When power to the motor stops, the electromagnet drops the cancelling magnetic field and the permanent magnet once again, clamps down on the friction disk attached to the end of the motor's drive shaft.

Unfortunately, the manufacturer used a pot metal cast adapter to fasten the brake assembly to the back of the motor. They also used only two #6 screws to fasten the adapter to the motor housing and did not use any Loctite. You guessed it.  The screws worked loose until one fell out and the whole brake unit was flopping around on the end of the motor shaft.  Lots of racket.

When I repaired the one under the kitchen slide it was some what accessible if you are small and skinny. I am 6'2 and 300 lbs. so you can imagine what a hard job this was to get finished.  They covered the heads of the attachment screws behind the brake mechanism so that had to be removed from the adapter before the adapter could be fastened back to the motor.

If you are a mechanic I know you hate engineers that do this kind of stuff.  In this case, it was hard to reach up into the belly of the RV between the axles to put the screws back in (with Loctite) but it was doable.

Guess what?  I have two slideout with this mechanism and the other one has now lost a screw and produces the terrible rackety-clankity noise when going in or out. Knowing what was wrong and how much work it was going to be to fix it I have not rushed right in to do it.

Today, I rushed in (where angels fear to tread, of course) and opened up the belly of the beast to tighten the adapter bracket back up.

Whoa! I said to myself when I had finally gotten at the motor assembly. The screws are loose but the adapter is BROKEN!  different game altogether.  Now I have to find a replacement or engineer something myself that will hold the brake assembly onto the motor housing.  Making it much worse is that there is no way to get at the screws that hold the brake to the adapter so to fix this puppy I am going to have to take the whole motor and gear box out just to tighten two #6 screws (assuming I can even find a replacement for the pot metal adapter).

So, until I can get on with it I just have to button the bottom back up to keep the critters out... but I was too pooped to do it today.... maybe tomorrow, I need to replace some of the insulation, anyway. It looks like it has been pulled out before, and just chunks stuffed back in there.  I will cut some batts to fit so it won't all come tumbling out into my face the next time I have to go into there.

ttfn

Budd