From what I've concluded, water and electricity still don't work well together.
~Hap

 

You're asking for a tricky one there.

I'd expect that any conventional electric motor is out.

Your options might be to have a clear (transparent) rotating disc (driven by an under-the-tank motor with a watertight o-ring seal) that's tucked under (or just over) the track, with the train mounted to the disc. It'll give the illusion that the train is riding on the track. Some people have used this method for super-tiny model train layouts.

You might also consider incorporating a magnet into the disc/train. In that way, the disc could be under the track (with a magnet glued to the disc in one specific spot), with a corresponding magnet (opposite polarity) on the underside of the train's loco. The former should pull the latter along.

Just throwing out ideas ...

However, one has to ask ...

WHY ????

TJ

 

I'd consider magnetic induction to supply power to the train, and a sealed drive train.

 

I'd consider a battery-powered train and silicone the ^&*% out of the seams. Realistically, I'd like to be encouraging, but I believe it's a non-starter. Electric trains get their power from charged rails: a salt-water bath should be a great conductor and enable you to destroy your transformer. If you seriously want to pursue this, you might take a hint from the larger aquariums and use Plexiglass tubing for the train to run under the water, a sort of clear tunnel. Trains are designed to push against air, which is much less dense than water, and the extra mass (your cars will fill with water, remember?) works against you, as well. Sorry to be a downer on your idea, but there's a reason there aren't real-life underwater trains without tunnels for them. Best wishes and my encouragement on the project, though. Aloha right back atcha!

 

What to do on a hot day in your backyard cement pond.


Remember nothing is impossible.


http://www.youtube.com/watch?v=dRwcJ1fjxM0


Add some Christmas decorations with lights too.:laugh:

Edit,

Looks like G scale?
Battery operated?
Must be weighed to keep it from floating?

 

What to do on a hot day in your backyard cement pond.

Remember nothing is impossible.

http://www.youtube.com/watch?v=dRwcJ1fjxM0

Dohh! Now I've seen everything !!!

TJ

 

Thanks everyone for your help.

I was hoping that someone knew how they ran the train or knew if it was commercially available in the YouTube video posted by Big Ed. I sent a comment askin the person who posted it how they accomplished it but haven't received a reply yet. It surely has to be a battery powered and weighted. I'm also looking to run a single engine which will have a gopro camera on it.

Is there a strong battery powered model on the market where I would silicone the crap out of everything?

Thanks again for any and all help.

 

The project is for filming an underwater scene. I just need a single engine and it'll have a small GoPro video camera on it. Itll be running on a circular track and 1 hour of run time is more than plenty.

 

A windup maybe? I see those on ebay all the time.

 

Find a battery powered locomotive and you may be able to make a go of it. You may want to look at how they water proof the RC boats. Many of them have a water tight compartment with a special bushing to allow the drive shaft out of the box without allowing the water in. Marx used to make an O scale 2-4-0 powered by 2 D batteries. There is more than enough room in the boiler of one of those to make a go at this. Good luck

 

Depending on the path that it has to take, I'd consider something other than a train that runs along a wire and is powered by a propeller and has an umbilical cord to the surface. I'm guessing the train tracks aren't the defining feature of whatever this is supposed to be filming.

 

It can be done but not to cheaply. You can get completly sealed engines LGBs feature this to an extent. You will need to have a seperatly sealed boxcar to house the batterys for the engine and have a cable go to it. then remember this is salt water. emensly corrosive to a model trains so it can't be left in for to long and needs to be completly washed down with bottled water or purified to clean all the salt out before it can cause damage.

 

R/C boats are far from water proof, trust me here!

We get water into the boats from a number of sources, but we can minimize the amount of water that does get in with a few simple measures.

1. Grease the prop shaft with waterproof grease. The prop shaft and stuffing box is usually a few inches long so it takes a long time for the grease to work its way up but eventually even with waterproof grease, water does get in the shaft. I usually service my speed boats after every day at the lake/bay and my tugs and other scale boats after a few trips.
2. Electronics. These need to be kept dry at all costs or it will cost you alot. We use watertight boxes, balloons, baggies or what ever else will work to keep this stuff dry. Salt water in the radio gear means sudden death to the gear, where fresh water usually can be dried out with some alcohol or WD40 and an air compressor and once dry it will work just fine again.

The motors run on DC and low voltage DC does not have enough power usually to conduct through salt water. Get over say 30 volts DC and you are going to start to notice problems ( and feel it too). AC current can conduct through salt water at a much lower voltage so i would not use any type of AC power delivery system.

Massey

 

That track looks like the plastic O gauge track you get with toys trains from toy stores. The engines are battery based. With enough epoxy, I'm sure you could seal everything up pretty tight and get it to work for maybe 1 minute.