Contra-Rotating Gearbox

[GBerger]

A little late to the party, but here is my answer to the Type A. Will be operational, imminently. 1/32 scale fiberglass hull and resin tower. Brass gearbox with scavenged gears.

[HardRock]

This looks fantastic.

[trout]

Late to the party? Gene, from the looks of your sub, you are right on time. More photos! Especially when you get her in the water.

[greenman407]

Nice looking subs. It brought to mind this picture:

[HardRock]

This is the old contra rotating set up...

[HardRock]

Components for the new WTC and new contra rotating motors
Now looking for a water pump and controller with 15mm diameter.

[HardRock]

This might end up being the slowest gearbox development in the history of model submarines. Neither of the crown wheel boxes ran very smoothly and the motor is so small that it tended to stall. Tried a tandem motor rig but the whole thing had to be within the WTC and that made sealing it almost impossible because water kept getting in through the inner drive shaft / outer drive shaft gap.

The new arrangement used bevel gears and keeps the box outside the WTC where it belongs. Also discovered that the rudders were way too small and relatively ineffective. Made a new lower skeg and rudder.

[trout]

Excellent work there! Where many would give up, I applaud your persistence. It will pay off in having a unique and wonderfully engineered sub.

[HardRock]

Thanks Mate. Continuing to stare at very small pieces of brass and wondering why I started this in the first place. How's the paint job on the Skipjack coming along?

[trout]

Paint was quickly put on (suggestion given by David) until it is been tested in open water. Then I will go back and see if I can do it any justice, like you did.
Still trimming it out.

[HardRock]

I'm sure that you've seen the excellent advice offered by Slats regarding trimming the Skipjack. Mine was OK but always difficult to run at a constant submerged depth. So after reading Slats' entry, I pulled out all of the lead and started again. The fundamental mistake that I made was in trimming for correct surface waterline first and then trying to fix the submerged trim. Doing it arse backwards really makes it hard to get right, whereas, starting with submerged trip works like a charm. Good luck with it.

[HardRock]

Quick question. When you built the 1/96 Aluminaut you fitted two small (waterproof?) motors. How did they hold up?

[trout]

So far, good. There is a tiny o-ring placed on the shaft, but the person who made the kit said it is not necessary. He has run many of those tiny motors in the wet and had only a couple fail.

[HardRock]

Where can I get a pair? I've been quietly churning away with the Alpha and it seems that the crawler system will have to be fully functional.. Sigh!!!

[HardRock]

More work on the Type A over the winter (with a short break at Jackson Hole for the One Fly!). I did the original as a skimmer and it was a lot of fun however, it seems that there might be just enough room to fit a ballast tank. Onward!