Hi, this is my first instructable so feel free to give feedback. There are many different ways to water-proof a servo, some of which are very effective but some are for a quick, non-permanent water-proof.
For Robotics, servos are a lot more useful than motors but for going underwater they both are useless so need to be "water-proofed" so in this I'ble I will show you how to do it with the most efficient method.'
www.societyofrobots.com/
For Robotics, servos are a lot more useful than motors but for going underwater they both are useless so need to be "water-proofed" so in this I'ble I will show you how to do it with the most efficient method.'
www.societyofrobots.com/
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Servos
The hobby servo in the last 5 or so years has become extremely popular among robotics builders. They are cheap and easy to use, but there is one issue with them - they aren't waterproof. Whatever people claim, servos are only water-resistant. This means that splashing water on them is fine, but full water immersion is like drowning cute kittens (very bad). This tutorial will list several popular ways to waterproof servos, then I will go into the best method (the SoR method) towards the end of the tutorial.
Servos are Only Water Resistant
Taking apart a standard servo you will quickly notice thin rubber rings around the edge, as shown at the bottom.These rings are there for near water-tight seals. Your main concern for water entering your servo is actually at the output shaft. Sealing the output shaft is always the most difficult part when waterproofing motors, and people do crazy things like magnetic coupling, etc. But as a hobbyist, using the most cherished of robot actuators (the servo, cough), we will have to do this low budget. But note, when I say low budget, I also mean very reliable . . .
Electrical Resistance of Water
The very first question you should be asking yourself is what type of water your robot will operate in, as it will make a huge difference in your design.
Pure water is a near perfect electrical insulator - meaning that it conducts electricity very very poorly. If you were to drop your computer into a tank of pure water, your computer will still work! So why is water normally bad for electronics? This is because in water there are impurities called ions, such as sodium or chlorine or whatever, that transfer electrons.
www.societyofrobots.com/
The hobby servo in the last 5 or so years has become extremely popular among robotics builders. They are cheap and easy to use, but there is one issue with them - they aren't waterproof. Whatever people claim, servos are only water-resistant. This means that splashing water on them is fine, but full water immersion is like drowning cute kittens (very bad). This tutorial will list several popular ways to waterproof servos, then I will go into the best method (the SoR method) towards the end of the tutorial.
Servos are Only Water Resistant
Taking apart a standard servo you will quickly notice thin rubber rings around the edge, as shown at the bottom.These rings are there for near water-tight seals. Your main concern for water entering your servo is actually at the output shaft. Sealing the output shaft is always the most difficult part when waterproofing motors, and people do crazy things like magnetic coupling, etc. But as a hobbyist, using the most cherished of robot actuators (the servo, cough), we will have to do this low budget. But note, when I say low budget, I also mean very reliable . . .
Electrical Resistance of Water
The very first question you should be asking yourself is what type of water your robot will operate in, as it will make a huge difference in your design.
Pure water is a near perfect electrical insulator - meaning that it conducts electricity very very poorly. If you were to drop your computer into a tank of pure water, your computer will still work! So why is water normally bad for electronics? This is because in water there are impurities called ions, such as sodium or chlorine or whatever, that transfer electrons.
www.societyofrobots.com/
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Very nice, I thank you this is some info I needed for a project I am doing.
Trying to build a Submarine for the dam where I live so I can see what the yabbies are up to down there.
I sail model boats and have used the following to seal my servos. I remove the lower servo case section, and paint the electronics, the bottom of the pot, and the motor case and the case around it with Freeman 1035T Brushable Mold Making Polyurethane Elastomer.
It is an off-white color and easy to see, so you won’t miss in the coverage. Paint the PC board on both sides, and over the cabling to the board. Once everything electrical is covered, let dry overnight and then reassemble the case, super gluing, (If you like? I’ve found that working the servo case into the boat often broke the glued area.)
I simply paint a thin layer of the Freeman 1035T on the o-ring areas, and put the case together and screw it together firmly. The o-ring on the top is a good idea, as well as lubing it with waterproof grease, like automotive Lithium-based wheel bearing grease. I strongly suggest relubing the arm O-ring each time you go out, (about 3 minutes at most!)
Check out Freeman Supply, a lot of neat stuff for a host of creative projects, and they have a great customer service staff that will help you answer those strange question folks like us come up with!
http://www.freemansupply.com/Freeman1035TBrusha.htm