smitty505000

Hello all,

I am new to subs but have been in the hobby for about 20 years. After a lot of web serching and research I decided to purchase a Dumas Akula and plan on installing a 2.5" mark 2 pressure hull from Mikes sub works. I want to use a propel system for ballast and have a question. If my ballast tank is 2.25" id x 6" long, how big of a copper cylinder do I need to make to be able to blow the ballast say 10 times using propel. If I understand it correctly, it is hooked up to a momentary switch on my TX and I could let out more than enough to empty the water by holding it too long. If this is the case I can make an electronic switch with an adjustable timer to let out only enough to empty the water. This would conserve my propel.

Any comments or sugestions are appreciated.

Thanks,
Neil smith

smitty505000

Hey guys,

I found the answer for volume of the pressure cylinder here http://pyerok.club.fr/Ballast_EV.htm
He has all the different types of ballast and how they all work.

My Akula arived and I started sanding the two halves. Also picked up some 3/4" copper pipe and ends for the propel pressure cylinder. I am modeling the entire sub in PRO-e 3d cad software to make sure everything will fit and found that the WTC looks like it will have to be a 2.5" x 6" battery compartment, a 3.5" x 6" ballast tank, and a 2.5" x 12" electronics/drive compartment. I feel a 2.5" x 6" ballast tank just wont be enough especialy after the pressure tank goes in it.

Smitty

Rogue Sub

If you have any more questions about this model me and a few others have done some good mods to the kit. Alot of it can be found by doing a quick search on wwwsubcommittee.com