Dave Welch new 3 inch WTC - DW-RCABS-R 3 inch

[anonymous]

Got Dave's new and beautiful DW-RCABS-R WTC.

This is just so well made and beautiful you want to hang it on a Christmas tree.

I am installing it in my scratch built GW and should have her running this weekend. I will show you video and pictures soon.

Dave why don't you tell the folks about you latest and greatest creation.

Steve











Edited By U812 on 1132353382

[markc]

Wow it looks great could

Wow it looks great could Dave offer such a complete package with the other WTC,s that he offers?

[bigdave]

Hi Guys,
This is the first

Hi Guys,
This is the first beta unit of a possible production WTC I designed that uses a new variation of the RCABS ballast system. Steve was kind enough to offer to in-model test it for me. (I really had to twist his arm). It uses a system I call RCABS-R, R for reverse. Our own Subron-8 member Crazy Ivan gave the idea to me. I took the idea and designed my version of a working system. With the RCABS you start with an un-inflated bladder and inflate it by using the air in the WTC causing a vacuum in the WTC. Connecting this vacuum back to the WTC will deflate the bladder again. This system works in reverse. You start with an inflated bladder and suck out the air and deposit it under pressure in a pressure vessel. Connecting the pressure back to the bladder will re-inflate the bladder again. My in water testing has shown this system to work very well. I then designed this 3” WTC around the system. If I go into production with it the WTC will be an almost RTR (or should I say RTD) ready to dive system. Complete with servos, ballast system, and drive system. It would be a limited production unit as it costs a lot to build them. With all the parts and electronics and labor. But I get requests all the time from guys that want to know if I sell completed units. They either do not have the time or the skill to build their own, but they want to have a running submarine. I designed it to operate a model in the 40-55” range. It is 24” long and 3” in diameter. I will see how testing goes and take it from there. I want to thank Steve for being my test pilot. I am glad you like it so far my friend. Hopefully the testing will go well. I told him to let me know anything he thought I should change or did not like about the system. Steve said “I will be all over it like a cheap suit”. I said I am DOOMED!!! Thanks Steve!
BD.

[pirate]

Dave,
What's the point of adding

Dave,
What's the point of adding an extra chamber? What's wrong with using the components chamber for the air source. I'm using this system developed by Dr. Broder, and with SubTech BHS linkage seals the negative pressure does not cause leakage, and it works wonderfully. Won't the added chamber you have make you have to add more weight to the model to make it submerge? I'm very curious as to your thinking.

Pete

[pirate]

Oh, I'm starting to see

Oh, I'm starting to see one benefit. With equal sized air chambers on each side, it makes it easier to center your ballast tank, but what else?

[bigdave]

Pete,
In this system there

Pete,
In this system there is no need for an air source. The bladder is full when you start. What is required is a chamber to contain the pressureized air. In my design that chamber is the front section of the WTC. The size of the chamber has to be equal to the volume of the bladder so at the max compressor pressure of 11 PSI all the bladder air can be compressed. Placing the air chamber in the front also counteracts the weight of the battery. Dave.

[wellington]

This looks good Dave. I

This looks good Dave. I am one of those who just dont have the tech skill to do a WTC as I have found with your Type VII wtc. I wonder if this new RTD type WTC would be a good match for the New Revell 1/72 Gato model?
cheers
Dave Goddard

[bigdave]

Thanks Dave,
When that 1/72

Thanks Dave,
When that 1/72 Gato kit comes out (Hopefully) I would like to test a twin motor version of the WTC in one. Hopefully Steves testing will go well. This is still an experimental unit. BD.

[pirate]

Okay Dave, let me see

Okay Dave, let me see if I understand.

You start out with a bladder full of air and a chamber full of air, and when the bladder is emptied, the pressure in the chamber doubles. So the vaccuum is in the bladder. So when you release the air from the chamber the positive pressure assures that your bladder will fill, and the boat will always rise. Is that correct?

I see that if my seals fail while my bladder is full, my WTC will flood. In your system this is not possible then, right? I was thinking of setting mine up this way at first, but then I found out the SubTech seals don't hold up to positive pressure.

But how do you get the chamber and the bladder full of air?

Pete

[bigdave]

That is correct. Although it

That is correct. Although it is not so much a vacuum in the bladder as it is deflated. In my design no vacuum or pressure is developed inside the areas with seals. The bladder is filled using a fill adapter and a Schrader valve on the front of the WTC in the pressure compartment. The bladder is just being inflated, not pressurized. BD.

[bigdave]

With the help of my

With the help of my good friend Seahorse (The computer wizzz) I drew up this simple diagram of how the RCABS-R works. Just like the RCABS, you can't get much simpler than this. BD.

[sam reichart]

Hi Guys,
This is the first

Hi Guys,
This is the first beta unit of a possible production WTC I designed that uses a new variation of the RCABS ballast system. Steve was kind enough to offer to in-model test it for me. (I really had to twist his arm). It uses a system I call RCABS-R, R for reverse. Our own Subron-8 member Crazy Ivan gave the idea to me. I took the idea and designed my version of a working system. With the RCABS you start with an un-inflated bladder and inflate it by using the air in the WTC causing a vacuum in the WTC. Connecting this vacuum back to the WTC will deflate the bladder again. This system works in reverse. You start with an inflated bladder and suck out the air and deposit it under pressure in a pressure vessel. Connecting the pressure back to the bladder will re-inflate the bladder again. My in water testing has shown this system to work very well. I then designed this 3” WTC around the system. If I go into production with it the WTC will be an almost RTR (or should I say RTD) ready to dive system. Complete with servos, ballast system, and drive system. It would be a limited production unit as it costs a lot to build them. With all the parts and electronics and labor. But I get requests all the time from guys that want to know if I sell completed units. They either do not have the time or the skill to build their own, but they want to have a running submarine. I designed it to operate a model in the 40-55” range. It is 24” long and 3” in diameter. I will see how testing goes and take it from there. I want to thank Steve for being my test pilot. I am glad you like it so far my friend. Hopefully the testing will go well. I told him to let me know anything he thought I should change or did not like about the system. Steve said “I will be all over it like a cheap suit”. I said I am DOOMED!!! Thanks Steve!
BD.

BD-
got a version that will drive a boat with forward dive planes? I'm thinking my 1/24 scale Type XXIII. (about 55 inches long)I need the front planes for control, and the rear planes connected to a APC device, so technically I need 3 control surface outputs (rear planes, forward planes, rudder) off the backend, or a passthrough to the front chamber for forward planes.

[steveuk]

Maybe I'm not fully understanding

Maybe I'm not fully understanding the operation of this system.. but if the bladder acts upon water in the ballast tank to push it out when inflated, isn't there the problem of outside water pressure keeping the bladder squashed if you go deep enough - crush depth of your bladder? At some measurable depth the outside water pressure will overcome the pressure exerted from the storage tank and when the valve is opened the bladder will remain deflated - and the sub will continue downward?

[anonymous]

I have tested the new

I have tested the new WTC and I have to say it works great!

Plenty of power and the gearing makes for a long run time. I tested for over an hour one one 1500 mah 5 cell nicad pack.

It dives most realistic. You can give little bumps to the gimbal and surface real slow or dive the same.

I found no real problems. One bad seal for the rudder that leaked a couple of drops in all that time. I simply replaced the seal and she's as tight as a drum now.

I couldn't be more pleased. This system will work well in a lot of different boats that take a 3 inch WTC!

Dave you've out done yourself this time. You should market this WTC for sure as there a lot of folks out there that neither have the time or the skills to build there own.

This WTC is turn key. Nothing to do except add your RX.

That's my report. After the holiday I will get video this weekend. My George Washington was as smooth as glass in operation with it's new WTC. Everything was so well balanced I could hover or move along at a very slow speed 4 ft. down. And look mom! No APC-4. for got to hook it up. Now I'm thinking the GW doesn't even need it.

I'm a happy Camper! Get one. You'll love it!

Steve

P.S. I went as deep as 7-8 foot in my pool. I was able to surface without any problems. I will never except in a pool go any deeper than that. Why? You won't be able to see it in any lake if you do and you risk losing signal.

At the lake I keep it to no more than 2 ft. Plenty for me.



Edited By U812 on 1132793415

[steveuk]

P.S. I went as deep

P.S. I went as deep as 7-8 foot in my pool. I was able to surface without any problems. I will never except in a pool go any deeper than that. Why? You won't be able to see it in any lake if you do and you risk losing signal.

At the lake I keep it to no more than 2 ft. Plenty for me.

7-8 feet of pressure is no small order.
I'd love to do a test in a controlled environment just to measure the depths at which such a bladder ceases to function. Figures would be re-assuring.

btw I'm not pouring cold water on this idea, just thinking from an awol sub point of view..I know some folks who dive thier boats in a flooded quarry.