Re: [PSUBS-MAILIST] I will build it!

I think the author of the PSUBS ethos had precisely this kind of thing in mind regarding the discussion below.

Joe

From: "Akins" <lakins1@tampabay.rr.com>
Reply-To: personal_submersibles@psubs.org
To: <personal_submersibles@psubs.org>
Subject: Re: [PSUBS-MAILIST] I will build it!
Date: Wed, 18 Jan 2006 05:47:02 -0500

Hi Rick. I didn't mean to step on your ambient design toes my friend. Regarding the ambient subs, I was speaking in general terms of what is mostly out there

as an ambient. As are the markham and sport subs as you mentioned, which are open to the sea as you mentioned. I haven't seen any totally dry ambients like

the one you are designing Rick. So perhaps in your case your ambient WILL be totally dry, but you must admit the norm is that they are not. How many other totally dry ambients are there? Could you name me a few?

Rick you mentioned doing a decompression dive in an ambient sub like it was normal procedure. No WAY I would recommend that! A decompression dive is tricky

enough using regular scuba. What if you were saturated from being too long pressurized and were unable to maintain your depth for decompression and shot

to the surface? Painful death. There is just too many things that could go wrong doing a decompression dive in an ambient sub. Is is possible? Yes. But is it wise,

necessary, prudent, or especially safe? No. Sorry my friend, but in this instance I take exception to your telling the newbies something that I feel is inherently dangerous

if not outright inviting suicide for them to go out and build an ambient and think it is ok to do a decompression dive in one. I really feel it is not responsible to tell them that is ok to do.

Perhaps I am not as able a builder as you are Rick, and my wetsub may not seem complicated to you even when it is all put together, but to me it has been

VERY complicated to build. and much more so than a strip built kayak, and it's just a wetsub. I had the basic body (I had to repair) of the sub as it was in the 1966 movie "Destination Inner Space" but I have had to rebuild the dive plane pivots

using materials at hand and creating things as I went along. There was a host of small things I had to do and make and I won't bore you with the many small tedious things

and will just mention SOME of the things. I fabricated a motor mount for it using an aluminum stop sign. That was a pain to do totally by

hand without ANY type of press or metal shaping equipment. My tools are very limited since most of them were stolen two years ago.. I'm building an easy escape canopy for it because of shark and gator infested areas where I go searching for WW2

aircraft wrecks. That hasn't been easy forming that canopy, plus I still have to install my internal hard ballast bladders and soft ballast pipes on the sides and route air to them as well as install the air tanks.

I still have to locate or fabricate a variable speed water and pressure proof switch for my motor control. I still have to compensate my motor against pressure. I still have to attach the battery pod, electrics, yadda, yadda, yadda.

Nothing I have done on my wetsub has been easy. Everything has had to be designed by me and created as I went along. A long slow process for me. I don't want

newbies to think it is a weekend project. I understand what you are saying about cruising in ease dry Rick. I know what you mean about wanting to tour instead of scuba.

Besides you can't drink your latte using scuba right? I understand that your dry ambient is perhaps somewhat cheaper and easier to build than a 1 atm sub and is without the problems

of having to construct and test a pressure hull. I am glad the ambient type design works for you Rick and who knows maybe one day I might like to try and build one myself if I get bored with my wetsub.

But I question the NEED and safety to perform an ON PURPOSE decompression dive in an ambient. If there is anyone else here at psubs who thinks doing a decompression dive in an ambient is safe, please speak up.

I do wish you the very best on yours and would be interested in knowing how you keep water or even water condensation out of the hull's interior with it being ambient.

As you said... "Bill, I luv ya, baby", I feel the same way for you and my fellow psubbers Rick. Please tell me you would never purposely do a decompression dive in an ambient. We'd like for you to be around a while.

Bill Akins.

----- Original Message -----

From: Rick and Marcia

To: personal_submersibles@psubs.org

Sent: Wednesday, January 18, 2006 3:20 AM

Subject: Re: [PSUBS-MAILIST] I will build it!

Bill, I luv ya, Baby, but, every time you post a reply about ambients, I get this crick in my neck and my hump changes sides ;-)

I am taking exception to a few of your points to the new guys. Permit me to adlib. Fling mud as appropriate!!!

----- Original Message -----

From: Akins

The three basic types are wetsub, where you wear full scuba gear and the boat is fully

flooded, 1 atmosphere sub, where the interior is completely dry and your hull atmosphere

is the same as at the surface, and ambient, which can be partially wet, or mostly dry.

Ambients are either semi-dry or bone dry. Magical Child, my Typhoon look-alike, will be as dry as an Idaho tumbleweed, especially with dessicant.

The wetsub is used basically as a diver propulsion vehicle

With a proper "windshield", lots of air and batts, and a dry suit you can tour for miles.

The ambient sub has either openings or a valve to let the water

pressure into the sub and then that water pressure is kept out of the sub by superior air pressurization of the

sub's interior.

Eez no so, Senor . . . well, ok, a semi-dry ambient is USUALLY open to the surrounding water, but, doesn't have to be. A semi-dry (Markham boat, SportSub) uses its cockpit as a variable ballast tank to control buoyancy. A dry-ambient is COMPLETELY sealed from the surrounding water. It has to be or the air compensating regs WILL NOT WORK. You can admit water into a VBT that is compensated, as well, but I suggest you keep it out of the cockpit proper.

The Markham sub uses the inverted cup principle to keep a bubble of air in the canopy. The SportSub was initially designed with an electronic sensor designed by Hugh Daskin of Vancouver that controlled the water level in the sub. Both were/are open to the sea.

Magical Child, a true dry-ambient, will be totally isolated from the ocean. Not only will it serve my needs as a touring vehicle but it will also be fully automatic in its depth keeping. I want to look outside and admire the view, not manage a machine (obviously I'll be managing depth dynamically)

Your operating depth for an ambient sub can not exceed normal scuba diving depths.

Por que? As long as you have taken the usual precautions (and keep your hand away from the hard ballast jettison handle) a decompression dive is appropriate. There would have to be an accurate way of maintaining stops, preferably on an anchor line, not moving. A sub is just a vehicle. Mixed gases on the other hand . . .

So the first thing you need to

find out is which of the three types do you want to build. None are easy.

If you've ever put together a strip-built kayak or canoe, then a wet or ambient sub isn't much more complicated. If you're not a diver, haven't used compasses, depth gauges, pressure gauges, regulators, BC's, weight belts, or dry suits, then, yes, putting a dry-ambient together can be intimidating because you just don't know what the heck to put into it.

By the way Patrick, an ambient sub does not require any special type of framing other than for

it to be reasonable sturdy. [snip ] As long as it is strong enough to hold together and take the weight of whatever equipment you put on it, it should be strong enough.

True enough. My dry-ambient will be a monocoque construction using epoxy over ply. Magical Child will be used for touring and her hull needs to be able to handle a rigorous seaway. We get twelve foot seas out here, and the water can be very confused with changing wavelengths in a matter of seconds.

A further note on ruggedness: a semi-dry ambient, if open to the sea, does not have to have a particularly strong cockpit. A dry-ambient, on the other hand, has to have a strong cockpit because of lag time in the compensating regulators. If you are plunging in an uncontrolled descent, you need to give the regs time to respond.

But be aware that an ambient sub will only let you go to scuba depths

and you have to be a certified diver and follow dive tables to avoid getting decompression sickness, and why

bother when you could just go to those depths with scuba anyway?

Well, I never!!! Bill, Bill, Bill - I want to TOUR. I've been diving since 1974. I'm tired of just seeing fish. I want to sit on the deck and watch the sun go down, see the water rush over the canopy, cruise through canyons, skim over wrecks, hover off walls, and look for interesting things like nude beaches outside of scuba swimming range. AND, I want to do it dry and comfy - remember my latte?

It has been pointed out in the past here

that it is almost as much work and trouble to build an ambient sub as it is a 1 atm sub that can dive much

deeper. The main difference is that one has a pressure hull and the other does not. The propulsion

systems are still required by both. Ballast and buoyancy systems are still required by both.

And exactly what do all those Lloyd's of London folks do out there - play cricket? A one-atm boat is orders of magnitude more complex than a strip built kayak that can sink. Magical Child will simply be a wooden boat that can indeed sink and will have a fantastic view. Period. A few basic instruments and controls. The only pressure type item will be overpressure valves that will be installed in the cockpit and cylinder storage areas in case of either an LP (or HP) line failure or an uncontrolled ascent. I doubt the exhaust ports on the regs would be able to dump fast enough.

So there.

Rick L

Vancouver

----- Original Message -----

From: Patrick

To: personal_submersibles@psubs.org

Sent: Tuesday, January 17, 2006 9:12 AM

Subject: Re: [PSUBS-MAILIST] I will build it!

you're kidding me...I can make that with a trip to Home Despot!

maybe I won't have to wait till I'm older and wealthier to build a sub afterall!

are there any plans or design guidelines on the psub site or elsewhere for

this type of vessel?

What should it be framed with?

What would the safe operating depth be?

~suddenly very excited,

-patrick

----- Original Message -----

From: JMDrocks2005@aol.com

To: personal_submersibles@psubs.org

Sent: Monday, January 16, 2006 6:10 PM

Subject: [PSUBS-MAILIST] I will build it!

Hello all, I'm new to the group. I spent 6 years in the US naval submarine service. 4 years 10 months on board the USS Baton Rouge (SSN 689). Now middle age has me by the b#$%s, and I want to build a boat of my own. I figure I won't have the time/money/space for at least 5 years. I count that as a benefit, as I should have a pretty good plan by then. in the mean time, I'll learn and share what little I know.

Jim