[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PSUBS-MAILIST] Re: Syntactic foam



A problem that is a underestimated in the submarine construction is smell how does this resins or syntactic foam smmell?.  In space crafts and military submarines there are persons who study the smell of many products.  In a close atmosphere a bad smell can make you crazy in a few minutes so you must cancel your dive or do many stupid things that under normal circusntances you will never do.  This very important factor should be not underestimated.
Best wishes
Jürgen

Mark Roberts - Harbortronics <Mark@Harbortronics.com> wrote:
FYI, you can make syntactic foam using two part urethane resins as well. These tend to be much lower toxicity than epoxies! I cast my own urethane parts fairly often, and did once mix in a bunch of glass microspheres. The microspheres truly are the consistancy of flour, so be really really careful to eliminate any possibillty of breathing them in... I don't know if the microspheres are the size to cause silicosis, but why test it! With syntactic foam, the goal is to maximize the ratio of the glass to the urethane, so you can end up with a really thick viscous mess. A lower fill-ratio would make it easier to deal with, but would increase the size of the float / reduce the buoyancy.
 
Microspheres are useful at really high pressures... i.e. 5000 ft deep kinda stuff. For shallow work, you might consider something easier and cheaper... for instance, I wonder what the crush depth of ping-pong balls are, when in a urethane matrix? How about shredded cork? 
 
Mark Roberts
----- Original Message -----
From: Joseph Perkel
To: personal_submersibles@psubs.org
Sent: Friday, February 09, 2007 9:58 AM
Subject: RE: [PSUBS-MAILIST] Submersible Planes, Syntactic foam, and Hydrofoil Race Boat Subs oh my

Brent,
I have not seen, (or may have missed), a published recipe/procedure for homemade syntactic foam that can be made with consistent buoyancy (lift) per sq ft of material. This would be helpful if Karl is willing to share the data.
In my case, I have not completely ruled out a sheet metal exostructure (ala Sea Otter). in lieu of being bothered with so much plugs/molds, lay-up, toxic resins...etc. Such a config, would likely make Alvin Jr. negatively buoyant when vented.
As for the "flying sub', keep doing the research,... the solutions to the engineering obstacles will be enlightening, and a great exercise in the rule/out, rule/in, aspects of design.
Incidentally, the Igloo was quite neat! Now you need to come to Florida and make one out of sand on S. Beach. You would likely make the evening news, and impress the girls!
Joe


From: "Brent Hartwig" <brenthartwig@hotmail.com>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: [PSUBS-MAILIST] Submersible Planes, Syntactic foam, and Hydrofoil Race Boat Subs oh my
Date: Fri, 09 Feb 2007 08:52:03 -0800

Joe,
I miss spoke, it's 3 microns, not 3 nano meter size spheres, and Karl said it was a real pain to mix. West Systems has a really low viscosity in warm temperatures and so it lends it self to this sort of thing. I have some ideas for a vacuum bag system for infusing low viscosity resin around the glass spheres in a manor that might be allot easier, not break the spheres when mixing them in the other manor, as well as get a lower density of risen to spheres. But we'll see what we see.
  I did ask him yesterday about how or if he was able to get even density and if he was happy with the results after allot of use of Idabel, and he's not gotten a chance to get back with me yet. I also asked him if he was getting any expansion/contraction problems between the fiberglass covering the foam, as well as the steel hull and the foam, and if he was having or worried about the foam being stuck right on the outer hull and not being able to inspect the whole outer hull. 
"So you want to fly over mountains in a psub eh?, May I suggest an instrument rating first! :)
Yes you may.  It's funny you would say that since last night talking with Michael Holt I was thinking that if I get my pilots license I would be allot more aware of design issues for a submersible plane.  I'm in no way a plane expert, just a fan at the moment. One of the issues I'm thinking about right now is a filter pump system to fill the wings and other areas of the air frame with clean water for submerging and keeping allot of dirt and crap out of the inner workings, if I don't have some sort of solid wing system which I don't see working because of weight and buoyancy issues. Having the wings work as a part of the soft ballast system was part of the idea. I'll also need a sprayer system inside the wings and other areas for spraying fresh or distilled water inside these areas to deal with saltwater. I've had plans for some years now to build and fly some day, a canard kit plane. So it was a natural choice for me to think about a canard style submersible plane.  I've also been a RC plane builder and enthusiast and I have a regular small aircraft landing stripe on my neighbors property.  I would likely want to install amphibious retractable landing gear on my submersible plane.  If I start working for Aerocet in the R&D engineering department I will have access to some great aerospace designers to work out some of these issues, and they might even be able to product most of the composite parts. The owner Tom Hamilton has designed and manufactured hundreds of Glasair kit planes in the past, before he started Aerocet Inc..
"As an amateur psubber and a former professional aviator, I am taken with the similarities as well as the opposites of the two disciplines. The two, with regard to weight/mass, could not be on more opposite ends of the spectrum. This is why composites, with their strength to weight ratio, is not a practical choice for pressure hulls."
There is also the concept of making an Ambient Submersible Plane, so you don't have near the pressure hull issues.  Have you seen the data on the composite hulls used by U Boat Worx?
Also the Deep Flight submersible has a light, cast aluminum, personal pressure hull in a configuration that makes the sub light in the air since it does not require allot of weight to submerge.
I was also thinking it would be interesting to look into making a Submersible Hydroplane Race Boat in either a 1 ATM or ambient design.
"So if one were inclined to spend the money and time, yes a flying sub is indeed possible. However, my guess is that a separate plane and sub, would be cheaper than trying to mate the two."
Cheaper yes, but not nearly as cool..  As far as I know a working fully submersible plane has not been made, so it's a pioneering thing we are dealing with, which gets my juices flowing.  If one puts the right group of experts together, I see it being a reasonable goal.  But for now I'm going to start with a RC model as proof of concept. There is always the design of making the plane bigger then it would normally need to be to carry two passangers and make most of the planes hull a free flooding area and/or soft ballest tanks. Dont forget I'm a submarine half full kind of guy.
Regards,
Brent   duck tape expert and butterfly chaser
 

 

From: "Joseph Perkel" <joeperkel@hotmail.com>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Sea Phantom Sea Trials
Date: Fri, 09 Feb 2007 14:08:28 +0000

Brent,
"syntactic foam, comprised of West Systems epoxy and 3 namo meter sized glass micro spheres"
.....I,... and I'm sure others, would be interested in a recipe for consistent results.
So you want to fly over mountains in a psub eh?, May I suggest an instrument rating first! :) One thing fun about this group, is brainstorming technical problems, practicality aside, to come up with potentially viable solutions....always an interesting exercise which occasionally pays off in other areas.
Ok, here we go.
As an amateur psubber and a former professional aviator, I am taken with the similarities as well as the opposites of the two disciplines. The two, with regard to weight/mass, could not be on more opposite ends of the spectrum. This is why composites, with their strength to weight ratio, is not a practical choice for pressure hulls.
If you want a psub to fly, you have to deal with a reality. That is that current technology will not allow you to get away with this in a single unit. Power requirement for such a payload requires fuel which requires volume, a situation of diminishing returns where a flying sub is concerned.
So you are left with a situation where your payload, (the sub/cockpit), would need to be mated with an appropriate airframe. This is not a unique concept, the Taylor Aerocar was successful in application, but a practical failure.
So if one were inclined to spend the money and time, yes a flying sub is indeed possible. However, my guess is that a separate plane and sub, would be cheaper than trying to mate the two.
Joe

From: "Brent Hartwig" <brenthartwig@hotmail.com>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Sea Phantom Sea Trials
Date: Thu, 08 Feb 2007 13:04:41 -0800

Joe,
I would like to see those links Carsten has. I think the only submersible I've seen with hydrofoils is the Bionic Dolphin VASH craft, and yes it takes allot of power.  They have a 425 horse power aluminum Corvette motor in it. For the depths that I want to go to, say 300 meters I'll have a separate pressure hull for the engine with the read head of that pressure hull being a hatch closed with a locking ring type system so I can get to all of the engine easily when out of the water.  I would also have a smaller hatch on top of the motor pressure hull for some basic work on the engine on the water. I like the Cummins diesels that can use bio diesel fuels.
I have a number of what I think are reasonably good ideas for retractable hydrofoils, but since there was already so much new technology in this design, I was thinking of doing them on a second model down the road when I had a better idea of what all goes into this type of craft.  I don't want to get bogged down with so many expenses and complicated parts that it took me twenty years to get it done.
The Sea Phantom from what I can see so far has allot of draw on those retractable sponsons when they are fully extended. Unless I'm not seeing a shapely angled rear section of those skis. Getting the nose up like that will help when dealing with waves but I think the Earthrace boat is allot better technology for making a smooth ride on larger waves.  The Earthrace boat how ever is very susceptible to hitting a log of the like on the waters surface at high speeds, and with that plumb bow it's going to do some damage. Of course hydrofoils don't do so swell when you hit a large log with them either.  There must be some story's out there of hydrofoil boats hitting things with there hydrofoils down.
You said it Joe, I want a "Sea Skimmer Submersible" and some day a flying submersible, and not just a ekranoplan mind you, but a real plane that can fly over mountains. But that's way down the road unless someone has a whole lot of money burning a whole in there pocket.  Can you say MORE POWER.
Don't forget my "Amphibious Submersible Four Wheel Drive Hydrofoil SUV" using retractable Michelin Tweel's that looks allot like a Star Wars Snow Speeder or Hummer. 
Then there is the "Ambient Night Rider KITT Submersible" starting with a 1983 Pontiac Trans Am that is cut up every way but Sunday, with a catamaran ski boat bottom. 
That's just the short list.      Joe, I'll bet your sorry you ever asked. 
But I have not totally lost it since I'm starting with a K-250 restoration with all the intellectual help I can handle. I've already got a bolt on catamara platform design in the works to mount to the K-250 for surface stability, wave protection when the hatch is open on the surface and walking space all covered in Rhino coat. This sub already sank once because a rogue wave got water in the open hatch when it was on the surface without anyone in it.
I'm talking with Karl Stanley and Doc right now about types of self mixing syntactic foam, comprized of West Systems epoxy and 3 namo meter sized glass micro spheres, to fill the space between the interior support rings after we install horizontal T steel supports between the rings.  This will give us great insulation value, allot of extra strength in the hull, and a extra factor of safety if the main hull starts to fill with water. This does not mean I plan to take the sub deeper then 250 feet when occupied. Once the syntactic foam is cured I'm thinking of Rhino coating the whole interior in a light grey color for easy cleaning. Since we are replacing all the thru hulls any way, we can have the new stainless steel thru hulls come further into the hull so we can trawl the syntactic foam around them. Of course we will need to use a metal prep cleaner then a high quality zinc primer on the sandblased bare steel.
Regards,
Brent
"Everything which is wished and can be imagined - can be achieved.
The optimist at heart, but not deprived feelings of a reality. "


 
************************************************************************ ************************************************************************ ************************************************************************ The personal submersibles mailing list complies with the US Federal CAN-SPAM Act of 2003. Your email address appears in our database because either you, or someone you know, requested you receive messages from our organization. If you want to be removed from this mailing list simply click on the link below or send a blank email message to: removeme-personal_submersibles@psubs.org Removal of your email address from this mailing list occurs by an automated process and should be complete within five minutes of our server receiving your request. PSUBS.ORG PO Box 53 Weare, NH 03281 603-529-1100 ************************************************************************ ************************************************************************ ************************************************************************
************************************************************************ ************************************************************************ ************************************************************************ The personal submersibles mailing list complies with the US Federal CAN-SPAM Act of 2003. Your email address appears in our database because either you, or someone you know, requested you receive messages from our organization. If you want to be removed from this mailing list simply click on the link below or send a blank email message to: removeme-personal_submersibles@psubs.org Removal of your email address from this mailing list occurs by an automated process and should be complete within five minutes of our server receiving your request. PSUBS.ORG PO Box 53 Weare, NH 03281 603-529-1100 ************************************************************************ ************************************************************************ ************************************************************************


Never Miss an Email
Stay connected with Yahoo! Mail on your mobile. Get started!