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amphibious tank?? Answered

We'll ive been building 2 tanks
first is a normal rc tank then the second is a better rc tank.
i plan to make a third one but i don't want it to be boring,so i decided to make it amphibious.Can anyone suggest me what method to dive and resurface?cause my plan might be to complicated

cheers

Discussions

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Toga_Dan

1 year ago

if u hav a snorkel and air pump, then minor leaks around the axles may not matter. As long as the air pump can keep up with leaks.

yes but this is a very small tank.A little more weight may cause distortion.I've started printing the body already :)

If you have a food sealer, vacuum pump or old fridge compressor you can test how good your PLA really is.
Print a closed cube or pyramid to keep the bridging away.
A size of 2 x 2cm is enough to have a good internal space.
Submerge in water after you tried your sealing method and pull a light vacuum.
If bubbles come out (a tiny few) it can be from within the layers, if lots of bubbles come out you might fill the thing with water.
A test on scale before and after will tell.

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Toga_Dan

1 year ago

The electronics need to be sealed against water. The motors are not entirely critical. Yes water will shorten their useful life, but not as much as you might expect. Meanwhile, You've got an awesome toy nobody else has.

Your antenna could be quite long to break the surface if need be. Reception may be better if the wet part is insulated.

yes i do know that.But the problem is i cant just let water breach the hull because this tank work by maintaining neutral weight.By allowing water it will drown and wont come up.Thats why im thinking using a 3d printed hole closer(dunno what to call it)so i can access the battery and swtich

Unless you use ABS and seal with acetone or ABS juice forget 3D printing to get anything watertight.
Consider rubber seals and screw connections to seperate the hull for acces to the elecronics.
Consider a battery pack in a sealed compartment or drop-in box with waterproof connectors.
This way you can change the battery quickly without a worry about opeing the actual hull.
Use the weight and location of the battery pack to level the craft ;)

yes i've research and found out ABS,its a plastic usually used in lego.But i also found an interesting way to make PLA waterproof.By making 3 layers and doing something ....its in reddit

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Downunder35m

1 year ago

So that you don't waste too much time and money I'll give you my five cents for free ;)
1. Problems:
To make anything float, sink and dive you need to be able to adjust the weight, e.g. the thing will sink due to weight and air in the ballast tanks keeps it floating.
Unless you just want to drive into the water and dump some rocks to get back to the surface you need gas and a way to control the filling of the tanks.
Remote...
Most RC remotes you can find will be quite useless once the thing is under water as it limits range like gravity does on how high you can jump.
Considering all the extras you need the remote will be costly.
Sealing....
Everything that moves on the outside will need a way to be fully water tight.
That means either to use fully sealed and external motor compartments or proper seals on the drive shaft.
Pressure....
Most people tend to forget about the fact that even in quite shallow waters a submersible can be subjected to quite a bit of pressure.
This means either the "hull" can fail or water can be pushed in through bad seals.

2. Possible options:
Instead of trying to make a tank sink and work under water it might be easier to combine something like RC dive and movemnet controls with a fully sealed tank designed from scratch.
After all if you can balance the weight properly you can use pods to move on the surface as well as under water.
Considering the amount of extra weight you would need for proper traction on the ground and that it might be very slippery....
I would use fully sealed compartments for the track motors and driveshafts and seals as used on bigger RC boats.
The remote is the biggest problem unless you only use shallow waters.
One option is to use a retractable antenna (preferable in the 2GHz range) so you can keep it on the surface at all times - just don't go into underwater caves or under submerged logs...

if thought all of your problem and solved most except sealing(which i am still currently trying to know how)

1.for diving i plan to use the tank neutral buoyancy and just just a ballast to add weight to dive and eject weight(water)to resurface a simple but ingenious plan i suppose.

2.For control.since i know ir signal cant penetrate well enough im planning to use radio signal.Im not targeting deep waters(1m should be sufficient) so it should work fine since i know a lot still can receive signal until 6m

3.Pressure:nothin new about that faced it already in previous projects.A thick 3d printed PLA with 3mm thickness should be fine

sealing:can you give me any idea of a design(3d printed that is water tight)

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Toga_DanDownunder35m

Reply 1 year ago

I'm gonna play devils advocate with ya soon, du35m. When I've a real computer in front o me.

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Toga_Dan

1 year ago

I'd do an image search on what has been done in the real world. For inspiration if nothin else.

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Toga_Dan

1 year ago

if I were to build what you want in full scale, I might secure 55 gallon drums along the edge of the veh, with provision to pump air into the barrels for floatation, or flood em.

I assumed you can't afford a real tank, but if you found/ made scale 55 gal drums for floatation, it could look real. And cool.

well lol i can,more accurately my mum can but she prefers to spend her money on bags lol.whats the scale which small rc car use btw?1:24???i forgot lol

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Toga_Dan

1 year ago

iirc, real tanks just have a snorkel. Not floating, they just drave along the bottom.

thats the problem!i want it to float and dive like a sub!

btw i solved that problem today!!ballast tank should do fine.Currently building it and gonna share it here soon

i think one of the problem is corrosion right?i solved it earlier(using corrosion x)by attaching thread to a rov???genius i haven't thought of that!