hub motor wire insulation repair

I just posted a wire identification issue on a 9C hub motor that has been answered but I have another question about repairing a cut in the insulation of 3 wires. I thought posting a new thread would be the prudent thing to do.

In order to get 2 thermistor wires through the axle slot I removed about 10" of the black wire covering that protects the hall & phase wires. In the process of doing that I also managed to slice the insulation on 2 of the phase wires & 1 of the hall wires. So I have 2 questions:

Can I safely leave the black wire insulation off of those 9 wires leaving them bare from just before the axle slot & just outside of the axle slot? I do plan to some how cover those wires where they enter & exit the axle. WITHOUT CUTTING THE WIRES?

Can I repair the 3 insulation cuts with a dab of epoxy & A small piece of SLICED heat shrink tubing applied over the epoxy while it's still wet. WITHOUT CUTTING THE WIRES?

Look closely at the yellow & blue phase wires & you'll see the insulation glued on over the wire.

I DO NOT WANT TO CUT THE WIRES?

I run this 9c at 72 V using a lyen controller set to 39 amps. It's all managed using a V3 Cycle Analyst. It seldom gets warm let alone hot. I also added ferafluid while I had it opened up.

I attached a picture.

Thanks
EZgo

That seems like a way better place to nick them than say at the axle exit where they're all tightly bundled. Pretty much anything will work because you have lots of room. Liquid electrical tape works well for what you need too... its a black rubber goo that you brush on that quickly dries to a rubbery coating.

That's a fantastic suggestion that I did not think of. Since I had to put this back together tonight I used a combination of hi temp silicone & a hot glue gun. (This is my only transportation at the moment.) That said I will get some of the liquid tape because this is not the first time I had to repair insulation. This is the most difficult & critical repair however.

I'll let you know how it works out.

Thanks

No prob... Hope it works out. But maybe stay away from hot glue holding stuff in the motor... It gets pretty hot in there and it sometimes gets soft and sags.

EZgo said:

That's a fantastic suggestion that I did not think of. Since I had to put this back together tonight I used a combination of hi temp silicone & a hot glue gun. (This is my only transportation at the moment.) That said I will get some of the liquid tape because this is not the first time I had to repair insulation. This is the most difficult & critical repair however.

I'll let you know how it works out.

Thanks

Click to expand...

Since I did not have the liquid elect. tape you suggested I used some RTV silicone to repair the wires before & after the axle & I used epoxy inside the axle. I then zip tied the 3 phase wires & 5 hall wires really well. I DID NOT USE the hot glue either. I'm satisfied that the wires won't rub through & the insulation repair should prevent any shorts between wires or against the steel axle.

Now my only long term concern is heat damage to the halls, wires & bearings but that was the whole reason for this project to begin with. I wanted to installed a thermaristor hooked to my CA V3 with the roll back protection starting at 90c & shuting down at 140c. I also added about 3 oz of ferrofluid to the magnets.

That said after a very hard 15 min. 4 mile run with no pedaling & pulling 30 to 39 amps everything seems to work as expected.

THANKS FOR THE SUPPORT

Careful with the RTV. Some of them release acetic acid when curing - highly corrosive to copper wire.

Ideally, you'd have at least some shrink wrap on those wires as they go through the axle. But if you must, just have a short piece at the actual entry point, covering an inch or so into the axle.