I just got off the phone with Castle's awesome tech support after questioning them about the water-resisting abilities of their Sidewinder ESC (which I just ordered). It turns out that, as I've read in other forums, the Sidewinder is "Highly Water Resistant." Basically what that means is that you can run it through water, but they don't say that for legal reasons. The guy I talked to said that they coat the circuit board in military-spec silicone sealant. That allows you to run it through freshwater just fine, and that it works perfectly for running through puddles, mud, and dirt with your truck. However, because saltwater is more conductive than freshwater, weird things happen when you run it through/under saltwater (i.e. it shorts out and breaks). Bottom line is, the Sidewinder is good to go in your truck if you want to run through the mud worry-free, and "go out and have some fun!" (Quoted from the tech support guy) .

They coat all of their ESCs making them "water resistant". Like you said, for legal reasons they can't advertise that, which means if you fry it they will not cover it from water damage.

is that the same with the mmp

This is true, however the guy assured me that it would be perfectly safe for puddles and mud, so I don't feel too concerned about the occasional splash

Not sure, but that would be interesting to know. You can call up CC and ask them, they're really nice people (# is on their site). Report back if you do

I also emailed CC and this is the response I got back:

All of our car systems have their circuit boards dipped in Silicon Conformal Coating. This is an electrical waterproofing product with a military specification to 100 ft in salt water. However, it is a very thin coating and does not electrically insulate the components on the circuit board. The stuff would waterproof an iPod to 100 ft but with the amount of current running through an ESC, in water electricity can jump between components in ways it is not supposed to. The reason we don’t electrically insulate the board is that anything that electrically insulates also thermally insulates so if we electrically insulate the ESC it will overheat.

What this means is that the ESC can handle moisture, splashing through puddles and wet grass etc. However, if you go through a puddle that submerges the ESC it will fail. If the ESC is submerged, it will not be covered under warranty.

--
Bernie Wolfard
Product Support
Castle Creations
235 S Kansas Ave
Olathe, KS 66061
913-390-6939 Ext 123

I ran my MMP through too deep a puddle after forgetting it was not water proof (previous ESC was). After that the car would not run at all, but luckily after drying, it was fine. There may be a coating, but as stated, it must be extremely thin since when I took the ESC apart I could not see any visible sort of coating.

had the cc sidewinder combo for over a year now and drove it hard all winter in my scx10, never had an issue but, I always worried about the water deal, anyway I was looking around trying to find a way to water proof my sidewinder esc and came across this forum, so I gave the cc sidewinder the old deep mud and under water test, no bags, balloons or silicone, 4 lipos of thick mud and under water rips, i'm happy and think its a pretty great product for a decent price thumbs up castle

Its thin enough that its more of a tint than a coating. If you ever see an older one, you'll notice a color diff. Its due to this coating.

Has anyone successfully increased the waterproofness of any of these ESCs?

I'm getting a mamba micro pro (considered a sidewinder micro that looks easyish to waterproof) for my mini-t which will be a offroad basher but it is going to get wet on occasion, one of the places i run is right next to a permanent bog and there's a perfect bit where you can see a natural corner to drive round, but if you get it wrong, you're in the bog.. my old cobra went in it hundreds of times lol

Should be even easier with the Sidewinder Micro, since it's just a heat-shrunk PCB...

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