RCAB and RCAB-R

[marvin harten]

Does anyone have diagrams and/or layouts for an RCAB and an RCAB-R?
Thanks.

Marvin Harten

[petn7]

Re: RCAB and RCAB-R

This might help (from BigDave's website):

http://www.frontiernet.net/~bwelch/ballast.htm

[Guest]

Re: RCAB and RCAB-R

http://artbrodersmodels.multiply.com/ta ... t%20system) There is an RCABS diagram in the slideshow, but I can't isolate it.

[Rogue Sub]

Re: RCAB and RCAB-R

viewtopic.php?f=58&t=9209

[crazy ivan]

Re: RCAB and RCAB-R

Also:

[tom m]

Re: RCAB and RCAB-R

Ok help me with this.
It seems to me by this diagram that the compressed air simply moves from the air chamber to the bladder and back.
Does the air ever leave the chamber during the dive state? I guess I am thrown seeing the compressed air at a constant amount always in the pressure hull. How does just transferring air from one item to the next make this thing work?
I must be missing something very obvious.

[boss subfixer]

Re: RCAB and RCAB-R

Tom,
The bladder is either outside of the WTC or encased in a ballast tank section of the WTC depending what you have for room between the hull and the WTC for the bladder to expand. If you have the room and it's outside then the bladder displaces the water that's between the hull and the WTC when you pump the air into it and up you come. If you don't have enough room between the hull and the WTC then you make a ballast tank section in your WTC with holes drilled in it, again displacing the water when you pump air into the bladder. Pretty simple actually. With both examples, when you release the air back into the WTC for RCABS or the air tank for RCABS-R the bladder deflates and lets the water back in and your on your way down. Of course the boat diving and surfacing when you want it to depends on your boat being trimmed out correctly.
Hope this helps.
Don

[bluefish]

Re: RCAB and RCAB-R

Are you rcabs-r guys using a pressure/vacuum switch to turn the air pump off when the bladder is empty?

[crazy ivan]

Re: RCAB and RCAB-R

A cutoff switch is not really necessary. When the bladder has fully collapsed, the pump will just attempt to pull a vacuum, something which these little compressors are typically not very good at, and the load current draw will usually drop slightly. You can measure how long it will take to empty the bladder on the bench, and you can mentally tick off how many seconds you ran the pump when diving the boat. If you over run it a bit, there is no harm. The only risk is if there is an air leak in the plumbing. Then the pump may ingest some water. This is generally not a good thing, so you should always inspect the system for leaks prior to starting your patrol.

[bluefish]

Re: RCAB and RCAB-R

Thanks for reply Ivan, I'm not at the stage yet, just getting back into building after life's curves have got in the way!!!
Feels good to get back to my project.