Dave Welch's Type 7 WTC build

[Guest]

Hey, Dave, I like the

Hey, Dave, I like the idea of having a sub that works. If the scale guys want an exact scale waterline, they can put the bladder under the WTC and have the waterline at the bottom of the hull. Only problem is that the hull would then be upside down!!
Seriously, though, different hulls have different requirements, and the RCABS is a very adaptable system. In a sub with saddle tanks, you could put modified inner tubes in the saddle tanks and adjust trim with foam and lead to get the desired waterline. In a nuke, if the bladder is above the WTC, you just need to allow sufficient room for the bladder to expand, and have a sturdy system to hold the upper hull down, so you don't lift the top half of the hull away from the bottom half.
Have fun experimenting and improving the design and function of your model.

[bigdave]

Art, that's priceless! Don't make

Art, that's priceless! Don't make me laugh, it's to early and I am not fully awake yet! Dave. PS- I thought of using the saddle tank area but it would have been to complicated to reproduce. As Skip always says (KISS). (Keep it simple stupid)

[tabledancer]

Steve,
Thanks for the info the

Steve,
Thanks for the info the other day and the explanation of the system.One more thing,is that a scratch built tray that I see supporting the air pump in the middle chamber and is each part of the WTC seperate from the others or is it a common chamber on the inside .Thanks again,you`ve been a big help .
T.D.

[anonymous]

TD,

Yes it is a scratch

TD,

Yes it is a scratch built tray made out of thin plex and supported by two rails of thick ABS. Dave came up with the idea and it works well.

It is a common camber as the middle end caps are open both fore and Aft. This is to allow more air for the RCABS system and for the cables to travel the length of the WTC to reach the RX in the small front compartment. Also the end cap to that compartment is open. I just dremeled them out or you could use a door nob cutting tool on a drill press. You just want a circular hole.

Hey your welcome.

Steve

[Guest]

Okay...now I'm a bit confused.

It's

Okay...now I'm a bit confused.

It's not clear to me how a ballast tank (RCABS or otherwise) is able to provide lift for a hull to get to the waterline when the ballast tank is at and above the waterline....at that point the portion above the waterline is just parasitic weight and not contributing to lifting the hull.

The analogy of a ballon sitting on top of the water is not a good one. The balloon sits on the "top" of the water because it takes very, very little of the internal (air) volume of the balloon to lift the weight of the balloon out of the water. In other words, I think it's a misleading analogy.

-Jeff

From a diver, perspective anything above the water is not lift. bouyancy bags only work when they are under water. never used and rcbs but thats what happens to a divers bcd

[anonymous]

Well it's finally finished. Got

Well it's finally finished. Got the dog bones today and made up the shafts. Got everything to fit in and attached all the control rods.

Then I ran everything to make sure it all works and it does. Well at that. Both forward and rear dive planes work together. Rudder action is great. Props turn so it's time to go.

Tomorrow I'll trim it. It's very light for it's size so a bit of ballast it all it will need.

I'll shoot some video as well so you can see how it all works.

Steve

[anonymous]

Here she is all finished.

Here she is all finished. The deck is just sitting in place without the screws right now. A good sign that everything fits.

Steve

[tabledancer]

Wow,everything really looks good, http://www.subcommittee.com/forum/icon_biggrin.gif

Wow,everything really looks good, .If it runs as good as it looks,though I don`t doubt it one bit. I am very ansious to see how it runs,becauce if you don`t mind I will use some of your ideas in my boat.
Regards,
T.D.

[anonymous]

Hey thanks. And sure. Go

Hey thanks. And sure. Go ahead.

Just trimmed her up. It was the most easy boat yet to do. A little foam and a little lead and she sits great.

Now to charge up the li-poly pack and see what happens. BTW. The pack didn't seem to mind being wet one bit!

Steve

[anonymous]

Perfection. This is the best

Perfection. This is the best boat I've built yet. I want to thank Dave Welch for a fine job on the WTC design. David Merriman. And all the rest of you that have contributed to my data base on this subject.

Here's the report.

Put it in the water. Raised her up on full ballast. She sat real nice. The power was over kill when I moved the throttle forward. Very scale at 25%. Hit the vacuum valve and she slowly dived a tad nose first (just like the real one). At 1/2 ft. I went to zero bubble on the dive plans. It was like I had an APC. Scopes sticking up out of the water like it was looking for a target. Pushed her down to about 3 ft. a leveled off. She trimmed perfect. Stopped as the length of the pool was running out and reversed and surfaced. I did this again and again.

Actually the boat turned very well. I could just about make it in the pool especially underwater. But it did very well on top too. The coupled dive planes seem to work very well so I won't change a thing there.

This boat is very scale in action. She moves smooth and big for something 3 ft long.

There's a few things I'm going to change tonight. I can use less ballast and be closer to the real water line. That's easy. I'm going to improve the deck mounting screws. And that's about it.

As soon as i get over this cold I'll shoot video. I'm feeling pretty bad right now.

Wow. Wow. Wow. I'm a U-boot commander now!

End report.

Steve

[tabledancer]

Looks like it was a

Looks like it was a good shakedown cruise .Good luck with the new boat and happy hunting,Kommandt
Salute,
T.D.

[anonymous]

LOL!!! Thanks TD.

Steve

LOL!!! Thanks TD.

Steve

[anonymous]

Here's the video. I'm not

Here's the video. I'm not real pleased as once again I couldn't get anyone to shoot for me but my trusty tripod. It's basic and simple but you can clearly see how well the boat works.

Again the pool just doesn't have enough room at 30 x 8 ft or there about. So all I could do is go forward and dive. Turn a little. Don't get me wrong here the rudders are effective.

Ich bin ein u Boot Kommandant jetzt!


Enjoy,

Steve

http://sneill.com/uboat/type7.wmv

[tabledancer]

Very good http://www.subcommittee.com/forum/icon_biggrin.gif .My hat

Very good .My hat is off to you.The boat seems to handle well,also I really enjoyed the background music,just rite.Big Dave also did a fine job with the kit.Can`t wait to get started on my own.
Salute,
T.D.

[anonymous]

Thanks TD. Getting going. You

Thanks TD. Getting going. You know it works great. Nothing to stop you now.

Steve