sea-worthy amphibious craft?

If tires rot in the sun and saltwater, why not paint them? You have to paint steel to protect it, and steel is cheeper than Monel. There must be a paint that is cheaper to use than reinventing vulcanized rubber tire.

 

Interesting point.

 

Painting flexible things doesnt seem to work very well. If its soft enough to flex, it rubs off easily. If its tough enough to not flex, it cracks.

I suspect that its the constant immersion of rubber in saltwater that is a problem. It rusts the steel belt, as well as cracking the rubber. The supporting metal (wheels, axles etc) of the rubber has to be a problem as well, but since it doesnt flex, paint would be a big help. No different than a trailer. Sealing the bearings and drive shaft is the bigger problem. Saltwater is compressed into the rubber seals, and eventually rusts the steel.

However, there is an oyster farmer here in Tassie who built stainless steel axles and differentials for semi amphibious trucks. It reduced the maintenance, but it still made for a lot of work.

 

"Saltwater is compressed into the rubber seals, and eventually rusts the steel."

If you have a source of freshwater on board then you could create a system to apply a counterpressure of fresh water from the inside of the seal area.

There are many makers of automatic lubricators that supply oil and grease to maachines, adapt that to supply freshwater to a seal at a pressure slightly higher than the pressure of the sea water. This would probably require two sets of seals, but if salt water is that bad, it could be worth it.

 

I'm thinking the tracks can be rinsed after stowing and the fresh water evacuated from the chambers.
I really think the salt water can be dealt with.

 

Off-road tire makers claim to have kevlar belted tires, if this is steel free then they would make a great choice for moving across the sand.

I was thinking about the DUKW and its central tire inflation system. Air is much more available on the sea than fresh water, so use that instead of water to provide back pressure against the seals. If the air leaks into the boat, no problem. A central air system could also power an air ride suspension, and air rotors to move the wheels.

 

This may make some craft suitable for assaulting a beach under fire or crawling above the hurricane surge but it'll all take away from what makes a good, responsive boat. I'd sure love to see a scale model, even in non-functioning mockup or computer generated form, to refine the idea.

 

Creosote....that's exactly the idea.
I have long believed in the benefits of stored energy in the form of compressed air on my "Dream Boat"...not the only stored energy of course.

Bataan ...I'm no where near clever enough on the computer to come up with a computer generated form...but I'm a big fan of scale modeling. I've been working with a meter long rough model for some time now. The design has now evolved sufficiently to necessitate building an updated model....I plan on starting the lofting Sunday.
We're talking "work" model ...not pretty, but dimensionally accurate.

I did contact a well known boat designer thinking that for a few grand I could get some preliminary lines and calcs done....that was naive of me.

 

http://www.spiegel.de/fotostrecke/fotostrecke-76402.html

from http://www.boote-forum.de/showthread.php?t=143441

 

oh yes - I want one ..... Santa !

 

I, too, think its cool.

 

Check the video: http://www.youtube.com/watch?v=Ceh9pJeD6QA

 

Amphibious vehicle Iguana 29: Out of the water
http://www.spiegel.de/fotostrecke/fotostrecke-76402-10.html


I like it, some nice photos too.

 

I wonder if the plans are for sale ?

 

Once you settle on "SeaWorthy" I see 4 types of amphibs....

1)SeaWorthy AND RoadWorthy AND Soft Sand/Swamp Worthy

2)SeaWorthy AND RoadWorthy(needs a ramp or gravel, but then does OK on roads)

3)SeaWorthy AND Soft Sand/Swamp Worthy(has tracks or limited drive like SeaLegs, not able to be used in traffic).

4)SeaWorthy AND RoadWorthy....with good provision for dragging itself past sand or mud with a winch and/or "sand ladders".


I don't know of any #1, because I wouldn't consider any military landing amphibs to be "seaworthy", even if some guy crosses the Atlantic in one. Some guy did that in a Klepper, but I wouldn't rate those as "off shore".

I'm not sure if there is anything but #3.


I'd like to see an aluminum hull boat with with recesses for truck size tires that would fold down, with either electric or belt drive with 4x4.

Basically a 30-40' cabin cruiser or trawler with 8' beam which would drive a bit more cumbersome than an RV. Like an underpowered, overloaded jacked up 4X4 RV. Able to drive in traffic and on HWY, just have to take the hills and curves nice and easy, but definitely boat based, not RV based like that converted bus.