Battle-hardened motors - who does that?

I’ve seen this video about battle hardening motors (epoxying the inside) and I wonder how much this is applicable to the esk8 world where motors take a bit of abuse. Arguably more than in robot battles. I’ve seen magnets or bits of them getting unstuck and leading to motor failure, so it sounds like a good idea to try and prevent that as much as possible. Apart from the sticky mess and some time wasted, any drawbacks?


Typically, motors already have this but not as much. Doesn’t hurt to add more and protect it. Just make sure not to have too much on the magnets where they end up rubbing on the stator. Probably better with an open motor too as it could cause the motor to get a bit hotter.


the glue blobs between the magnets are usually just balance weights. i would not do this unless you know exactly what you are doing. maybe doesn’t even matter because were not spinning our motors on high enough rpm.

How 8k rpm is not much 12s battery and 190kv motor=9500rpm (at 4.2v)

The motor wouldnt blow up because of few extra grams here and there but it could wear out the bearings faster

thats relative;)

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I don’t trust him…he is copying @mmaner


The real solution is to build your own motors. The issue with magnets breaking is China uses shitty epoxy, because good expoxy will cost $15 per motor instead of $1 per motor. The. They do the same on the stator, $1 epoxy instead of $15 professionally engineered motor winding epoxy. They also don’t use vacuum chambers to remove air pockets in the epoxy used in the windings that trap heat in the stator and cause shorts. Some don’t even use spacers to properly align magnets (though many do).

But this is how China builds motors. They are cheap for a reason. All of these steps cost more money. This is beyond choosing $2 bearings, with fake nsk markings on the (instead of $30 per motor in bearings), aluminum instead of steel, larger air gaps, and weaker n42sh (or less) magnets that cost $3 or less per motor instead of $15 per motor for n48sh magnets.

Just add it all up, and you’ll see why China does what they do. Motors work for a bit, but they will break. A good motor should last for 1,000,000 miles or more.

Imo, it’s not worth trying to modify the motor as you’ll likely get it in the wrong place and the stator magnets will then rub.


I would definitely be worried about obnoxious rubbing.