WTC Tests are in - Sucess across the board!

[bob the builder]

I just finished tub testing my new WTC. No leaks after one hour at 10" depth. This is the setup that uses the rad fan motor from a car as the main propulsion unit.

As you can see from the pictures... she puts out tremendous thrust. This pic was taken at 1/2 throttle, with a low battery!



I'd highly recommend the motor to anyone with the room to implement it. It's a 10-pole, 1800 rpm motor w/ built in capacitors. It cost me a grand total of $4 CAD at a surplus store, brand new. It will draw a max of 4A under very high load, and 1A free running / low speed.

[safrole]

Very interesting. What hull and

Very interesting. What hull and general setup will you be using?

[bob the builder]

Full details of my entire

Full details of my entire project are on my site, the Nautilus Drydocks. She's a 1]http://members.shaw.ca/rcsub/images/modelpics/final2.jpg[/img]





12V system running off two 6V - 7Ah batteries. WTC houses a Modelcontroller 25A ESC, auto trimmer, and auto depth keeper, Subtech's SES-II electronic switch, Thor's micro failsafe, and four servos. Radio is an Airtronics VG600 6-channel



Edited By Bob the Builder on 1064955226

[safrole]

So you're THAT guy. I've

So you're THAT guy. I've been to your site many times and am always impressed. I don't know which is better, your sub work or your website design. I'll look forward to seeing more of your progress.

[anonymous]

Spectacular Bob! Impressive model and

Spectacular Bob! Impressive model and web site.....but can you do a James Mason impression? LOL!

Regards,

Steve Reichmuth

[tmsmalley]

Hi Bob -
Super job! I

Hi Bob -
Super job! I can't wait to see your boat in the water. Is your WTC a "Greg Sharpe-ified" version of a D&E unit?

[bob the builder]

Tim,


HIGHLY Sharpified (that should be

Tim,


HIGHLY Sharpified (that should be a verb). The only thing that was really stock is the endcaps, and even those are modified.

The WTC sections are the result of a collaberation between myself and Greg in terms of design, and Greg did the handiwork in his secret lair. The idea is to make the ballast tank specific to each model (as they are really just a piece of pipe with a little hardware) so that adjustment of the WTC for different models is unnecessary. Additionally, the motor compartment is also separate so that different models can utilize the exact motor / gearing combination that is perfect for them. This was important to me because my next project is a dual screw model that I'm plannig to run Dave's twin Graupner 500's on.

The original WTC was modified to separate the ballast tank, and to allow for additional features. The modified WTC has four servo outputs, and two electrical outputs, as well as the depth controller input hose.

Greg is a master craftsman, and very good at what he does.

I understand that he will finally have a fully functional website up and running in the very near future. Once it gets up and running, I'll post the url for everyone.

For anyone that doesn't know, Greg sells excellent plans for a large number of Russian and US nuclear submarines, as well as two different Verne-styled Nautilus' and plans for his (should be) patented WTC and watertight transmitter cases.

[Guest]

Looking good, Bob.

I'd like to

Looking good, Bob.

I'd like to add a note about the propulsion motor.

For guys(or gals!) who would like to incorporate a motor similar to Bobs in their subs, a few points to mention.

Scrap yards (car breakers) are an excellent and very cheap source for motors. Here in the UK, surplus stores are few and far between, but breakers are very prevalent, and with old cars being disposed of at an ever increasing rate, there's rich pickings to be had for modellers who wish to break free from the "mabuchi" mould.

Modern cars are absolutely jammed with quality electric motors that would cost an arm and a leg in model shop (if you could buy them, there) and generally exhibit the following characteristics-

High torque low speed winding

Multi pole armature- i.e. 13 poles or more, fan motors often have upto 22 poles. How slow can you say "smooth low speed running!"

Wide can design for wide armature i.e. 2" to 3" diameter or greater. With the addition of low RPM, this means no gearbox required for all but the largest of models.

Wide voltage range- these motors can take voltages anywhere between 6-18 volts without any difficulty.

Low current draw.
------------------------------------------------------------
Disadvantages?

These motors are generally built to last, so tend to be a little heavy.

Consequently they're generally only suitable for models of around 40" upwards.

That's about the only disadvantage.

Pricing?

No more than £2-5.

Places to look for the motors?

Electric radiator fan.

Electric heater (interior) fan

Electric window motors.

Windscreen wiper motors.

As an example I recently opened up an electric radiator fan motor, which came off an old Ford.

Inside, I found four heavy duty carbon brushes, a 22 pole armature approximately 3.5"diameter. Ballraced front bearing and bronze rear bearing. Cast aluminium can.

This motor will last for ever!

Would suit a boat of 50" or more.

Cost £1.

Nuff said!

Cheers

Andy

[Guest]

Hmmm, one thing I haven't

Hmmm, one thing I haven't noticed on your module/WTC is the presence of schraeder valves (tyre valves).

Personally, I wouldn't run a sub without them.

Fit one in each of your cylinders (usually in the end cap) a few pumps with a bicycle pump will soon show up any leaks when submerged into the pond.

Costs a few pence and is good insurance for your boat.

Andy

[bob the builder]

OH HO!!! Do you think

OH HO!!! Do you think the infallible Greg Sharpe did not think of this? I, too, was interested in utilizing a schraeder valve on the endcap, but Greg came up with a better idea.

Please notice the black length of tubing exiting the wtc from the center of the endcap]http://members.shaw.ca/rcsub/images/modelpics/wtcfinished2.jpg[/img]

This tubing is approximately 1/8" O.D. and houses my receiver antenna. The end is capped with a brass plug to stop water from entering the WTC.

When I'm making up the end caps, I simply unplug the tubing. The compressed air in the WTC exits via the antenna housing.

If I want to test for leaks, I simply plug a tire pump with a ball inflator pin into the end and give it a few pumps. The air exits quite slowly through the tube, so I could actually plug the end while the air is still venting in order to keep some overpressure inside if I wanted to.

This idea frees up real estate on the end cap (which I have little of if you'll notice the picture).

I think it's a great idea!

[Guest]

Well that's the radio compartment

Well that's the radio compartment taken care of.

How about the cylinder housing the motor?

Andy

[bob the builder]

Um... errrr. I cast a

Um... errrr. I cast a magic "no water enter here" spell on it.

I guess I'll get around to adding one in the near future.

Thanks to everyone for their comments. Keep the suggestions coming!



Edited By Bob the Builder on 1065240321

[Guest]

lol, okey dokey!

Just remember Sod's

lol, okey dokey!

Just remember Sod's law- if you think something won't happen, it probably will!

Mind you a bit of water won't harm a motor to much, probably help cool it after running at 'Collision speed'!

Andy