aluminum Kayak

[RDB]

Has anyone seen or built an aluminum kayak.

Sea Kayaker mag. just did a story about www.royak.com alum. sit on top kayaks, orig made out of aircraft drop tanks , I'd love to see a shiny alum. sea kayak, surely could be done along the lines of a hard chine pygmy boat, just replace the wood templates w/ alum? Wonder about the weight though...

-Sam

[RDB]

Grumman makes a pretty sweet canoe, lighter than most wooden and far more reliable for lengthy trips. Just looking for small projects to keep welding shop running during the down time. The plywood plans might be the way to go, probably similar to 3/16 alum. thanks for the link.

[duluthboats]

I believe the light Grumman canoes are made from .055” thick aluminum. It may look like just a simple canoe but a lot of engineering went into it, so it would keep its shape and still be light. They do have a tendency to dent easily. I had a late 50’s aluminum canoe it was made from .100” thick material, it was indestructible and I know the guy I sold it to is still using it. It weighed 110 lbs. I can only guess how much a kayak made from .187” thick aluminum would weigh.

Gary

[Not A Guest]

Kayaks get full of water.

You really don't want a boat that sinks.

[duluthboats]

Thats what they make float bags for.

Gary

[Arrowmarine]

First I will quickly admit that I have no experience with canoes. But I do have loads with aluminum and I think that 3/16 is WAY to thick to consider. 24" x 96" x .1875 weighs about 42 lbs. For an eight footer you would need two of these(i am guessing) for the sides. Seems heavy to me ( again, no canoe experience) With the proper design you should be able to go as low as .050. Certainly .080 As gary noted .100 aluminum construction would be tough as nails. By comparision I just rebuilt a 21' race boat, designed for speeds in excess of 90 mph on white water rivers. Other then the doubler in the keel it is constructed of entirely of .080. Aluminum is super tough with the right application. Look into it.

Hope this helps.
Joey

[mattdayton]

I started today building a miniature copy of a kayak's tip (leading edge or trailing edge), just to see if my sheetmetal working skills are up to par. I think that, with some work, a viable kayak could be built, with the appropriate bulkhead and stringer substructure design. I'm an aircraft mechanic in training, so I am more likely to try flush riveting (a la aircraft surface drag reduction) with some sort of a sealant on the inside (stealing the design of metal fuel cells from aircraft) and paint on the outside for water repellency. The only problem, however, is that I can only cut and shape sheetmetal, as I have not yet learned how to rivet yet. I think that going the riveting/sealant route is far easier than trying to master welding sheet aluminum. There's pros and cons to both construction techniques, but I'm all for simplicity in design and construction.
We'll see how it goes, and see how things develop. There's only one way to find out if it's possible!

[sal's Dad]

Consider a heavy, durable boat - 1/8" plate (.125), welded, with integral bulkheads. This material weighs about the same as 3/4 ply, or about 2 to 4 times what a stitch-and-glue boat will come in at.

Such a boat will probably require NO framing or stiffeners- just stitch-and-weld the panels!

Yes, it will be heavy - figure about 50 square feet of material, or 100 pounds. But you will have eliminated ALL questions about durability and rough usage, and never have maintenance. Once in the water, the extra 50 pounds or so will make little difference, in a medium to high volume design.

With respect to adhesives/sealants, please share any information or experiences!

Sal's Dad

[abindoff]

I don't think an aluminium kayak would do much for paddler comfort. One thing I like about my wooden kayaks is that they always feel 'just right', not too hot and not too cold.

Regards,
Aidan

[duluthboats]

Here are a few things interesting about aluminum canoes. http://www.newsday.com/community/gui...ory-navigation

1. Something to think about is that even the lightest aluminum canoe is heaver than most comparable composite canoes.

2. Aluminum will bend in only one direction unless you form it and then it must be soft and heat treated after forming.

Gary

[MarkC]

I would love an Ally kyak! I fully support your endeavours, however, as stated in the article (see link above) how are you going to beat a 17footer for $775 dollars? Mabe worth talking to the guys at Marathon Boat Group.

four former Grumman and OMC employees and an upstate investor formed Marathon Boat Group Inc. and began pressing out canoes again at the old Grumman plant in Marathon. Today's 17-footer sells for $775, plus shipping, compared with about $205 in 1953, according to Greg Harvey, Marathon's sales manager.

"Aluminum is no longer the king, but it has its own market," said Harvey. "We virtually kept the canoe from disappearing."

Have you checked-out the http://www.metalboatsociety.org/forum.htm web site?

[Jack D Davis]

I'm getting closer to starting my own welded aluminum canoe. I've had a few projects to get out of the way first and still have a couple, but almost there.

My plan is my own, shown on my website at http://www.hmds.ws/Canoe.htm

Material will be either 5052x.080 or.065. MIG welded. I've tested .080 and it worked great, but I'd like to go lighter. I have some .065 to test, but haven't done it yet.

Jack

[sal's Dad]

Looks like a fun prokect, Jack!

One comment: It looks like a wide, high-volume canoe - wider than anything I can recall seeing. Have you paddled a canoe of roughly those dimensions? It seems to this canoe novice that the geometry of paddling could be awkward.


Good luck, let us know how it goes!

Sal's Dad

[Jack D Davis]

Yes. It is wider than average and it COULD be problematic to paddle, but I'm hoping not. Longer paddles may help in that regard. I designed it more for fishing and placid water and wanted it stable. Note that the sides are triangular tubes for strength and unsinkablilty. Those tubes will either be watertight voids or foam filled. Thwarts should not be necessary. This first one will be my own and a prototype for testing and modifications.