OTW NACKEN BUILD THREAD HMS Neptun

[ffr2608]

Tom,

The drawing is pretty much what I was thinking. Cutting the red and white and building a small circuit board to solder everything to. Looking for any options here. I am familiar with the beads too. Should I try them as well?

D

[ffr2608]

Still trying to work out the electrical glitching.....For now, I'm working on the hull seam.


D

[ffr2608]

Just finished up the control surfaces. Nice and smooth and no binding. Does anyone have a source for the double U joints that can handle more than the Dumas dog bones? Need it for 6mm.


Thanks,

D

[greenman407]

I havent been able to find any metric ones but , 6mm is .236,,not too far off from 1/4"(.25) These are plastic so they are light weight, shouldnt have enough weight to throw it out of balance and cause vibration.
You could use these. Stock Drive Products doesnt have a direct link to each individual product so I posted the link to the catalog page and showed a picture of the product. Call them and tell them what you need.https://sdp-si.com/eStore/Catalog/Group/812

[He Who Shall Not Be Named]

Hey! Rube Goldberg: Why the intermediate rocker-arms in the linkage???!!!!.....

[Subculture]

Prop Shop do a nice range of heavy duty couplings-

http://prop-shop.co.uk/index.php?id=26&section=store&sub_section=products

You can use one at the motor end, and a second at the prop end.

Also Raboesch do ball and cup joints with the splined inserts like their cardan couplings. Inserts are available in imperial and metric sizes. Plastic but should be more than strong enough for this model, as they're listed as suitable for i.c. use.

http://www.cornwallmodelboats.co.uk/acatalog/raboesch-couplings.html

[ffr2608]

Dave, You know this......
With yoked together fins, I am limited to about 70 degrees of travel. (yoke hitting the drive shaft and appendage shaft) That is fine for conventional boats but with an X tail, hard right and hard dive (sometimes caused by pitch controller) can travel way past these amounts; colliding with the shafts.....NO YOKES
The intermediate is an easy way to give equal throw at each appendage because the arms coming out of the tube are not always linear in direction. A bit of wiggle will give uneven angles on the planes.
Just a couple extra bucks in hardware and no added slop if you build it tight......

D

[He Who Shall Not Be Named]

Can't argue with that, Darrin. Thanks.

M

[ffr2608]

WTC mounting finished and all linkages are done. Ready for a float and trim test. Just need to pick up an inflatable pool to start trimming.

D

[greenman407]

Looks really good. Looks like you used pick-up truck bed liner paint on the insides. Good Idea. And you also found your drive shaft coupler.

[ffr2608]

I finally got the Neptune in the test tank today. Surface trim done in about 5 minutes. Submerged trim within a half hour. Fastest one I have ever done.
First shot is leak testing the tube. 3rd shot is of the steel bars I used. Came out of some workout ankle weight belts. (local pool says "NO LEAD") Sprayed them and the blue foam with Plastidip. It really does a good job of preventing rust. It also seals the foam up better and makes everything black. Very clean......Final shot is the finished periscopes and tower. Just a few details to do in the bridge area.(electronics, zincs, etc...)


D

[ffr2608]

Here is the final surface trim at about 95% full tank. Tail heavy like they used to run them on the surface. Also started cleaning up for final paint.

D

[He Who Shall Not Be Named]

Nice! It's a joy watching a Master at work.

M

[ffr2608]

Thanks Dave. It was noted elsewhere that the nose is too high. Trim was a bit off at the time of photo but I plan to have it sit like this.....

[trout]

Is there any chance that the aft end was caught under the edge of that "test tank"? I had one of those, and they are great, however with the rounded, tubular sides, I needed to make sure the sub was not resting against it while trimming.
Your sub is really looking great. I think any adjustments to trim become minor at this point, don't you?