Foamey Yak

[Wobbly Wheels]

For anyone looking for plans or inspiration for a design of their own, Phil Bolger did a lot of small boats that were developed from flat panels that should translate well into foam. Look especially into his punt designs - they're along the lines of the PD Racer that CC built. There's also a book that came out of his collaboration with Dynamite Payson called Instant Boats that might be worth a look. Bolger's "box boat" designs give you the most buoyancy and ease of construction at the cost of traditional 'boat-y' lines.

Bonnie, I used a keel strake like you're talking about. Mine was 5/8" sq yellow cedar and was sacrificial to take the wear of beaching. It did stabilize the tracking a bit, especially since I had a trolling motor clamped onto the gunwhale before I put the deck on, but I ran it only half way down so it wouldn't hinder turning.

[Mary C]

OK, I got that, nice way of saying little old lady. I know I could build one I built my TD didn't I well almost. Life keeps getting in the way of finishing. I like your design GPW, I am looking around for some big Foam blocks. I am going to talk with my trucker friends and see if any of them might know of some. I just know it has to hold me a battery and the little electric motor and my fishing gear, a little ice in a cooler with a little ballast.

Mary C.

[GPW]

Apologies , Mary that was just a general expression ,speaking metaphorically, not directed at you specifically ... But , if the boat fits .... go Fishing !!! Besides , I have a couple years on you so it’s more like .. even Grandpa could build one ...

Ps. That’s all I want for mine too ... SIMPLE !!! ... and Thrifty ... and it has to fit in the back of the pickup truck ...

Here’s a fishing tip I learned from a professional fishing guide ... wear camo shirts ... Fish can see too ... It works ...

[Mary C]

Look here silly, I do have a cents of humor and right now I am wearing a fully geared camo with deer rifle so I know, all game sees camo and know to get outa the way at least that was my luck this morning. I saw two doe but looking for the big buck!!! I really have to finish gluing the shelves. I am off and will be thinking about the yak and camo shorts. As the say down here, now Y'all have a nice day now ya hear.

Mary C.

[GPW]

What a coincidence ... I’m wearing camo too ... It just seemed like a camo Sunday ... Not hunting , just wearing it because it was Cold !!

It was a very Nice day !!! Thanks !!! hope your's was too ...

[GPW]

First thing first , must see if I can still get those foam blocks down in Lafitte.... If not , this project comes to a grinding halt ..

But we could get Lucky ! And “projecting “ from that idea ... was thinking about getting 4 blocks ($80) and popping out a fishing Barge... Can’t think of anything easier ... or thriftier ...

You know , with a little streamlining , we could take this Basic idea and make it more like a Yak ...

[GPW]

Put a call in to the foam guy .... Got his voice mail , left a message to call me .... So he’s still there...

[clermont cubby]

GPW

Good luck with the build. Love my foamie Yak. There were skeptics on my boat build site that the foam skin would not work, but I have been very satisfied with the results, light weight and easy to paddle.

Larry

[Mary C]

Larry we know about the doubters, believe me I had doubts too but I decided to go with it like an experiment. I was very happy with the outcome. Your yak works and to your expectations .....then phooey on the doubters. We believe.


Mary C.

[GPW]

You know, the idea of a foam boat isn’t exactly new.. Back in the early 70’s , a friend had a little foam sailboat ( I forget the name ) we used to sail around at at South Padre Island... It was just moulded foam (beads) with a plastic outer skin around the outside ... a little sail slipped in , simple daggerboard ... Not much to it but it worked for several summers of Fun... then got sold off, and he bought a BIG sailboat ... If it worked then , it’ll work now !!!

Anybody know the flotation figures on a cubic foot of foam ?

[GPW]

OK, just found this ... “ per this web site you will need one cu ft of foam for each 55lbs you want to support in the water. “


Rough calculations of the “Barge" ... 4’X8’X1.8’ = 72cu.ft.. 72 X 55 lbs = 3960 lbs That seems like a LOT of Flotation (unless I buggered the Math ? ) ... Certainly enough for a simple fishing barge .. eh ???

[tac422]

Doc,
The "Barge" wouldn't be solid foam, so I think your calucations probaly shouldn't be based on strickly the overall dimensional data ?
I'm reminded of floating on a car hood.... No flotation in the metal, but the amount of surface/ water displacement is why it floats...

[clermont cubby]

[quote="GPW"]You know, the idea of a foam boat isn’t exactly new.. Back in the early 70’s , a friend had a little foam sailboat ( I forget the name )"

GPW

sailboat is called a snark. In the '70s they joined with Kool cigarettes for a promotion. $88.00 and Kool carton top and you received a sailboat.

That boat was the introduction for many new sailors. The Snark is still being sold today.

Kool sailboat.png (22.88 KiB) Viewed 419 times

Larry

[GPW]

Tac, maybe you can explain that better to me ... My Math is dead AWFUL ....

CC, I believe that’s the one (wasn’t KOOL though ) ... Much more expensive now ... http://www.meyersboat.com/#/snark/models/Super%20Snark

[tac422]

Doc,
OK, I did a little Googling...
It doesn't matter what the boat is made out of.
I don't think it matters how much foam you use. It matters how much the water you displace weighs vs the overall weight of the boat. If the boat is lighter than the water, it'll only displace the amount of water that weighs the same as it does.
If you had a 1 cubic foot boat that weighed 62 lbs, it would displace 1 CF of water (62 pounds), it would sink to where the top of the boat was even with the water . 1/1
If that same cubic foot boat weighed 31 pounds, the boat would sit 1/2 out of the water ( only displacing 1/2 a CF of water).
If it was a 2 cubic foot boat that weighed 31 pounds, the boat would sit 1/4 out of the water because it would still only be displacing 1/2 a CF of water. (over the 2 cubic foot area.)
confused yet... ? I am !
Think about a styrofoam cup, it weighs very little , has little foam, and only displaces a small amount of water.

Buoyancy = weight of displaced fluid vs the weight of the item.
Water's density is approximately 62 pounds per cubic foot, (62.428 lb/cu ft)