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Author Topic: Waterproofing servos  (Read 6536 times)

Rodgearing

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Waterproofing servos
« on: January 06, 2015, 08:14:10 PM »

What do we use to waterproof our servos.
Plasti Dip?
Anything else?
Fred
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Sub driver

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Re: Waterproofing servos
« Reply #1 on: January 06, 2015, 08:36:03 PM »

Hi.
I think a few people have tried to use servos in the water as it were with varying degrees of success with the plastic dip method and o rings on output shafts etc..... But I think its a waste of time and money personally.... put them in the dry pressure hull and use waterproof linkages they will last much longer with much , much less hassle.  O0
Regards Sub.
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Subculture

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Re: Waterproofing servos
« Reply #2 on: January 06, 2015, 10:50:25 PM »

For me the main snag with having lots of little independent watertight areas like servos, is that unless you're prepared to open them up and inspect them before every run and one of them does leak, generally the first you will know about it is when it ceases to function. Or to put it another way, you have lots of little boxes to open up and check. If they're dipped in something to provide a vulcanized coating, then you don't even have that option, and just keep your fingers crossed that the modifications hold up.

Far easier to maintain one watertight chamber, designed right for the job.

Davy1

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Re: Waterproofing servos
« Reply #3 on: January 07, 2015, 09:08:31 AM »

Hi Fred,

I agree with all the answers above.

I have tried waterproofing servos (Plastidip) with poor results. (It is one of these topics on the net where people only report their successes!)

I would only contemplate doing it again for a non-critical function (turning a gun etc. ) and with a servo regarded as 'disposable'.

David
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Rodgearing

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Re: Waterproofing servos
« Reply #4 on: January 07, 2015, 09:13:40 AM »

OK thanks all noted.
I wish to put a vale inside a ballast tank, which I was going to make, rod with disc on it washer underneath spring etc as a crude attempt at a vent valve for the tank.  I suppose I could dip and make a small enclosure.  Or???
Fred
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Arrow5

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Re: Waterproofing servos
« Reply #5 on: January 07, 2015, 10:34:35 AM »

What do we use to waterproof our servos.
Plasti Dip?
Anything else?
Fred
Try a product called Corrosion X, used a lot in the aviation world (full size and model)  to waterproof electronics. Enclosing RXs in rubber balloons and other rubber enclosures can be subject to condensation inside such closures.
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coolbumble

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Re: Waterproofing servos
« Reply #6 on: January 07, 2015, 06:50:59 PM »

Hi

I note that waterproof servo's are available on eBay and some at a price less frightening although I have never used them if you only require one or two why not purchase them?
As far as a valve for venting a tank I have used modified aquarium air valves also available from the same source. However controlled by a servo inside the WTC.
Ian  :-))
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Subculture

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Re: Waterproofing servos
« Reply #7 on: January 07, 2015, 07:21:08 PM »

I would advise caution with waterproof servos. Many of them are really just designed to be waterproof against splash e.g. model cars running through puddles etc. Not resistant against water pressure.

An exception are some of the Hitec servos which feature an IP67 rating. However a check online will reveal they very expensive, and personally I can think of better ways to spend money on a sub.

salmon

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Re: Waterproofing servos
« Reply #8 on: January 08, 2015, 01:24:23 AM »

Just to add to the people above that are saying don't do it! Don't do it. I was going to do that for a sub I have and contacted some of the people that posted years ago about doing it and all of those that replied said they do not do that anymore. Many did have success, but it was short lived meaning it will leak and fry sooner or later. One individual, whom I cannot remember his name said that following servos failed almost immediately.
Make a small box to house your servo or better yet, use a pushrod going through your WTC to move the valve.
If you need examples let me know I can show you some.
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Rodgearing

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Re: Waterproofing servos
« Reply #9 on: January 08, 2015, 09:09:16 AM »

Hi Salmon yes please show me some examples
Fred
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rickles23

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Re: Waterproofing servos
« Reply #10 on: January 08, 2015, 01:02:44 PM »

Hi,

I use Waterproof servos for my Footy yachts:

Savox Waterproof Standard Digital Servo.

Easy way to test them as per manufactures advice is to run them in a glass of water and keep them submerged for a few days.

One of my yachts spent four days submerged in our local river which is salt water and still runs well a couple of years later.

Regards
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Rodgearing

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Re: Waterproofing servos
« Reply #11 on: January 08, 2015, 01:35:52 PM »

Hi,

I use Waterproof servos for my Footy yachts:

Savox Waterproof Standard Digital Servo.

Easy way to test them as per manufactures advice is to run them in a glass of water and keep them submerged for a few days.

One of my yachts spent four days submerged in our local river which is salt water and still runs well a couple of years later.

Regards
Yea but that's a target its not a submarine  ;) ;)
Fred
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rickles23

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Re: Waterproofing servos
« Reply #12 on: January 08, 2015, 02:04:38 PM »

It may be a target but the point is that the waterproof servos worked even after being submerged in salt water. Regards
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Rodgearing

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Re: Waterproofing servos
« Reply #13 on: January 08, 2015, 02:37:01 PM »

Thanks Sport
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salmon

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Re: Waterproofing servos
« Reply #14 on: January 09, 2015, 02:53:58 AM »

Maybe it will work, but read the specs to be safe. I know I will check them out.
When I get home tonight I will post pictures of some of the vents out there. Maybe a little video too!
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salmon

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Re: Waterproofing servos
« Reply #15 on: January 09, 2015, 08:27:18 AM »

As far as vents go here are some ideas.


This first one is on a D&E 1.25" Sub-Driver. This one uses magnets, pretty cool idea.

The pushrods are moved by magnets as well.



This one was made by Will Oudmayer for one of his piston WTC. The video shows the servo movement.
https://www.youtube.com/watch?v=-KnPeVAP6sQ
The vent is a conical aluminum or aluminium piece with a o-ring to seal it.


Another one that also uses a servo, but this one transfers the push pull motion (unlike Will's rotational motion) to open and close the vent.

The vent is rubber.



The seal that is used is an o-ring, but there are many ways to seal the push rod.
On an earlier post is another vent, so be creative. There are vendors that sell mechanisms for a vent. MikesSubWorks does [size=78%]http://www.mikessubworks.com/page1.html[/size] look under compress gas system parts on the left hand side.
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Subculture

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Re: Waterproofing servos
« Reply #16 on: January 09, 2015, 02:25:29 PM »

Does Will's boat use a partially aspirated tank in conjunction with a smaller piston trim tank? Otherwise I'm having a hard time envisaging why he'd require a valve.

tsenecal

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Re: Waterproofing servos
« Reply #17 on: January 11, 2015, 07:44:09 AM »

Does Will's boat use a partially aspirated tank in conjunction with a smaller piston trim tank? Otherwise I'm having a hard time envisaging why he'd require a valve.




the conical valve allows the "air" to leave the ballast tank, holes in the bottom of ballast tank allow water in.  the schrader valve is connected to a small tank full of "gas", filling the tank when opened.
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salmon

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Re: Waterproofing servos
« Reply #18 on: January 11, 2015, 05:22:55 PM »

My fault, I said it was one of Will's piston tanks, it is not. It is a gas system. So, I think that is where the confusion is coming from. Will's piston tanks are all piston no other ballast system needed. Thank you Andy for catching that.
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tsenecal

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Re: Waterproofing servos
« Reply #19 on: January 11, 2015, 09:28:47 PM »

hmm...  knowing what type of ballast tank on that specific submarine was, (i was watching while Tom made that video) i didn't even notice that Tom had called it a "Piston Tank". as Tom says, that specific ballast tank is not a piston tank.
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