In a previous video, I demonstrated how tap water reacts with electronic circuits. Along the way, we concluded that an Arduino Pro Mini board will not work reliably under water without the help of a protection against the water.

That is when I coated the Arduino in an unknown substance which was actually just plain old nail polish. After letting it dry, it protects the circuit from the water, and thus it functions without a problem. For simple and small circuits, this method is suitable and seems to not influence the electrical connections negatively.

But let's say we have an ESC that we want to operate under water now. An ESC is an electrical circuit that connects in between a BLDC motor and a power source and controls the revolution speed of the motor according to an input signal. It's not only important to protect the electrical connections from water, but also guarantee that the coating material can handle the heat transfer from the heatsink.

So, in this video, we are going to test out nail polish, silicon, and potting compounds to see which material is best suited for this job. To start this experiment, I unpacked three identical ESCs whose label and heat shrink tubing I removed afterwards. I made sure they all work properly by connecting each to a motor and a power source and utilizing my homemade ESC tester.

To make the tests more accurate, I got myself a few type K thermocouples which are basically just two metal wires connected together in one point in order to create a voltage difference proportional to the temperature. I secured them to the heat sinks of the ESCs using compatible thermometer circuits, so I could easily measure the temperature of the heat sink.

The initial temperature measurement showed that the heat sink reached 27.5 degrees Celsius after letting the motor rotate for around ten minutes with an input signal of one point five milliseconds. This will be our reference temperature for later.

For the first test, I went with the nail polish, which does work on one side without a problem. However, it brings some problems when it comes to completely encapsulating the ESC plus its heatsink. After submerging the ESC and connecting the input signal and power, I noticed that the ESC still worked without a problem. However, while adding the motor rotates for ten minutes, I also noticed that the speed was fluctuating and bubbles were produced by the ESC. These weren't positive signs, but the motor still rotated successfully for ten minutes while the ESC reached a temperature of 20.6 degrees Celsius.

After repeating the test in air, the ESC reached a temperature of 28.2 degrees Celsius, not as low as without the coats, but that was to be expected. The important question is how will the other two materials perform?

To find that out, I used a sheet of rigid foam on which I marked the outlines for all the pieces of two cuboids in which the ESCs would fit. Then, I cut out all the pieces with a box cutter and used hot glue to connect them to one another. I made sure to use plenty of hot glue to guarantee that the constructions were waterproof.

Once that was done, I prepared a tube of high-temperature silicon and covered the bottom of the first cuboid with it. Afterwards, I pressed the ESC into it and then buried it underneath another layer of silicone. While that was drying, I got myself the two components for the potting compound which is the stuff that manufacturers usually utilize to waterproof electronics or hide their circuits from your sights.

I doubt that many peers can read the German warning text on the bottles so let me summarize it be super careful when dealing with the stuff and protective gloves and glasses are mandatory. For my mixture, I utilized shot glasses to measure four centiliters of component A and four centiliters of component B. After mixing them together, I poured the mixture into the cuboid.

The result of the potting compounds were certainly not perfect but nevertheless it looked quite fascinating. After once again reattaching the motor and power and submerging the ESC it turned out to work just fine as well. The last thing to do was to repeat the by now well-known temperature measurement which also delivered values pretty similar to the previous ones?

So, all in all, the three methods are capable of waterproofing electronics while simultaneously featuring sufficient heat transfer capabilities. Personally though I would recommend nail polish for small and mechanical unstressed projects since it is so quick and easy to use and putting compounds for more complex projects since it is truly the professional way of waterproofing electronics and can also withstand a lot of mechanical stress. Silicon though was a bit too messy for my taste and its due to its viscosity here rather difficult to apply evenly.

With that being said, you should now have a good idea of how to waterproof electronics effectively. If you liked this video don't forget to like, share and subscribe Stay creative and I'll see you next time.

WEBVTTKind: captionsLanguage: enIn a previous video I demonstrated how tap water reacts with electronic circuitsAlong the wayWe concluded that an Arduino Pro Mini board will not work reliably under water without the help of a protection against the waterThat is when I coated the Arduino in an unknown substance which was actually just plain old nail polishAfter letting a dry it protects the circuit from the water, and thus it functions without a problemFor simple and small circuits. This method is suitable and seems to not influence the electrical connections negativelyBut let's say we have an ESC that we want to operate underwaternow in case you don't know and ESC is an electrical circuit that connects in between aBLDC motor and a power source and controls the revolution speed of the motoraccording to an input signalHere it is not only important to protect the electrical connections from water, but also guarantee that the coating materialCan handle the heat transfer from the heatsink.So in this video we are going to test out nail polishSilicon and potting compounds to see which material is best suited for this jobLet's get startedThis video is sponsored by JLCPCB amanufacturer of quick PCB prototypes for 10 yearsUpload your Gerber files to get high quality PCBs for ridiculously low prices and make your projects look more professionalTo start this experiment, I unpacked three identical ESC whose label and heat shrink tubing I removed afterwardsTo make sure they all work properly I connected each to motor and a power source and utilized my homemadeESC tester to see whether they would all work, which they didSo I got myself a few type K thermocouplesWhich are basically just two metal wires connected together in one point in order to create a voltage difference proportional to the temperatureAnd secure them to the heat sinks of the ESC's we've kept on tapeby utilizing the compatible thermometer circuits we can easily measure the temperature of the heat sinkWhich went up to twenty seven point five degrees Celsius after letting the motor rotate for around ten minuteswith an input signal of one point five millisecondsThis will be our reference temperature for laterFor the first test I went with the nail polish, which does work on one side without a problemBut it should be fairly obviousThat this methods bring some problems when it comes to completely capsule aiding the ESC plus its heatsinkBut anyway after I then submerged the ESC and connected the input signal and powerI noticed that the ESC still worked without a problemBut while adding the motor rotate for ten minutes. I also noticed that it speeds was fluctuatingand ubbles were produced by the ESCThose were all not positive signsbut the motor still rotate is successfully for ten minutes while the ESC reach a temperature oftwenty point six degrees Celsius andAfter repeating the test in air the ESC reached the temperature of twenty eight point two degrees Celsiusnot as low as without the coats, but that was to be expectedThe important question is how will the other two materials perform?To find that outI use the sheet of rigid foam on which I mark the outlines for all the pieces of two cuboids in which the ESC's would fitsthen I cut out all the pieces with a box cutter and used hot glue to connect them to one anotherAnd I made sure to use plenty of hot glue in order to guarantee that the constructions were waterproofOnce that was done. I prepared a tube of high-temperature silicon and covered the bottom of the first cuboid with itafterwards I press the ESC into it and then buried it underneath another layer of siliconeAnd while that was drying I got myself the two components for the potting compoundWhich is the stuff that manufacturers usually utilize to waterproof electronics or hide their circuits from your sightsI doubt that many peers can read the German warning text on the bottlesso let me summarize it be super careful when dealing with the stuff andProtective gloves and glasses are mandatoryFor my mixture I utilized shot glasses to measure four centiliters of component BAnd eight centiliters of component A which I then poured into a small silicon bucketafter mixing the two components together for three minutes with a plastic steerer at the speed of450 rpm I let it sit for around 2 minutesAnd then poured it into the second cuboid in which I positioned the ESC beforehandNow after one day of waiting the silicone and the potting compound were hardenedBut it was quite obvious that there was something wrong with the siliconeSo I tried to free the rigid foam pieces from the silicone which revealed that the inside was still liquidsWhich forced me to add a bit more silicone and wait for another dayafter repeating this process a second time the silicone coats was finally complete andafter reattaching the motorSubmerging the silicone covered ESC and powering it all it looked like everything still worked flawlesslySo I repeated the same temperature measurement under water and in airWhich ultimately delivered values which were pretty close to the previous onesNot badTo finish this experiments I freed the putting compound from the cuboid walls which was this time a lot easier to accomplishThe result of the potting compounds were certainly not perfectbut nevertheless it looked quite fascinating andAfter once again reattaching the motor and power and submerging the ESC it turned out to work just fine as wellThe last thing to do was to repeat the by now well-known temperature measurementWhich also delivered values pretty similar to the previous ones?So all in all the three methods are capable of waterproofing electronics while simultaneouslyfeaturing sufficient heat transfer capabilitiesPersonally though I would recommend nail polish for small and mechanical unstressed projectssince it is so quick and easy to useand putting compounds for more complex projects since it is truly the professional way ofwaterproofing electronics and can also withstand a lot of mechanical stresssilicon though was a bit too messy for my tasteand its due to its viscosity here rather difficult to apply evenlyand with that being said you should now have a good idea of how to waterproofelectronics effectivelyIf you liked this video don't forget to like, share and subscribeStay creative and I'll see you next time