Re: batteries in pressurized compartment...?

[shawl@torchlake.com (Jonathan Shawl)]

Hi all,
My comments mixed in below...

asmyth wrote:

> Dear support group,
>
> I am afraid with all the excitement over the intellectual property issue, my
> teeny question about batteries went unanswered. Is the answer too obvious? I
> can't imagine nobody has encountered this issue... sealed batteries in a
> pressurized compartment, therefore they get squeezed. Do I need to drill a
> hole in them? Or is that a Tarzan solution? After all, don't the makers
> claim AGM batteries don't leak even if the case cracks? On the other hand if
> there is NO air in them, I'm OK. But I don't feel like cracking open a brand
> new battery to find out.

Good questions, but I will leave that one for the battery experts in the group.

> On another note...
>
> I just took a painful decision over the weekend. I'm building my sub one
> discrete system at a time, and just completed the control surfaces and
> controls, most of the work being the manufacture of 4 actuators. This was my
> first completed system, and it made me feel almost *done* because I can now
> stand in my garage with a joystick and "fly" a virtual sub consisting of
> nothing but control surfaces and the hardware to move them! (SOS, call a
> shrink, I've done that for hours).

Oh don't worry about that. I just call it a practice dive or training dive. I
made many such dives in my driveway when I was building my sub, complete with
sound effects and everything! :-) By the time the sub was ready for the real
water dive I was a experienced pilot ready for the first dive. My wife is a RN
and works with shrinks. She hasn't made me an appointment yet so I guess i'm
normal. Normal for this p-suber at least!  :-)

> Well, the actuators work great, probably even well enough, but now they are
> functional they only seem to inspire new ideas for making better ones. And
> considering the unforgiving environment our boats have to function in, I've
> decided I'll shoot for the best actuators I can make, even if it breaks my
> heart and -- more importantly -- delays the project. Sigh, the first set of
> actuators took me 8 months. Fortunately some of the improvements are
> simplifications, so the second set should be much easier. But just in case,
> I'll complete only ONE of the new design first. Who knows, it could give me
> more ideas.
>
> - Alec Smyth

Are you referring to dive planes or motor direction actuators? If they are dive
planes you may find that they are not all that effective on a small, slow p-sub.
I have 3 sets of direction motors on my sub, in fixed positions, and no moving
control planes at all not even a rudder. I wanted it to be as simple and
reliable as possible. It works great just by reversing the prop direction of the
motors, Up-Down , Left-Right, Forward-Reverse. I use a joy stick and relays for
this and fly it just fine.
Jon Shawl
http://www. yel-o-sub.com