Hi Kyle

Welcome aboard The MEW Forum

Gee you have picked a hard project.

I guess you have tried the following Google search?
**LINK**

The words inexpensive and safety are mutually exclusive. If you are not familiar with designing this sort of craft I suggest you seek professional help before starting. Building and using an untested design could be catastrophic.

All commercially designed and built submarines are given extensive and rigorous testing both in the dry dock and at sea before being put into service.

Regards
John

Edited By John McNamara on 24/08/2015 15:19:21

A 'wet' sub (i.e. no pressure vessel – pilot is in standard scuba/dive gear) is a much less risky DIY venture…

**LINK**

Truly a Darwinian pursuit! I hope you have no family or dependants.

At 30 feet, the pressure is about 13 PSI (using old units). Thick PVC would make an adequate coffin but to my knowledge nobody has made a submarine from that material.

Plenty of home made mini subs are made and tested in the waters around Florida. Try searching "narco-submarine" for some ideas.

It sounds as if you are planning to have a pressure hull – I wouldn't think a kayak would be much good for that (shape for one thing).

Amongst numerous other issues to consider – PVC can be brittle at low temperature.

If you are actually planning a propulsion device for a SCUBA diver, things may not be so tricky.

This project sounds rather like a life support system, so people may be cautious with giving any advice.

I guess the overall pressure on a kayak will be 20-30 tons or more. at 30 feet deep.

Without wanting to put a damper on this idea, I strongly advise that any design is checked by a qualified engineer as failure will almost certainly have fatal results.

Personally I would go for building an ROV first to get some real experience.

Neil

A cautionary tales near the end of this:

http://www.cia.gov/library/center-for-the-study-of-intelligence/csi-publications/csi-studies/studies/vol-58-no-4/pdfs/Tale%20of%20Two%20Submarines.pdf

Neil

.

Do you intend to use it for running 'coke' for Columbian drug barons.? If so you will need good sonar fitted to stop you bashing into sunken prams and cars as you go all stealth like on your deliveries up the local canal.

Nick

I hope this project is not a way to bring illegal immigrants into the country?

Just to calm things down, I can remember seeing a TV show (USA origin) and they had 2 man submersibles but they had a moon pool in the bottom of the sub. This sub would carry 2 people and the could exit and enter the sub without any problem. The conning tower was where the person steering and diving controls were There were windows to see where you go. Electric propulsion.

Now, this would not suffer from compression as it had this moon pool which kept the water at bay by a slight over pressure in the sub. More than likely made of fibre glass/resin and they always seemed to be yellow colour. Must have been safe as there was a nubile woman in it!

The passengers/operators used no scuba gear and free dived from it. I am sure it was commercial at that time.

Clive

Ok..back to the basic engineering..in a dive bell mode..the bell is at no pressure( across wall) ..if the bottom is open and air was at any pressure..the level woukd rise or fall to equalise.

Look up Sleeping Beauty for a one man steel canoe/submarine, or Chariot, a two manned torpedo like craft.

Ian S C