Sonnet 17.5 - sponsons

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paddlesheep
faltbootemeister
Posts: 149
Joined: Tue Apr 08, 2008 1:37 am
Location: Vancouver BC

Sonnet 17.5 - sponsons

Post by paddlesheep »

Decided a few months ago that it was time to build a Sonnet and construction is well underway. Completed the skinning frame yesterday and will start on the hull and sponson sleeves this week.

I went back and forth a bit deciding which one to build. At 220lbs the Sonnet 16 is not enough. I started the frame with the intention of building the new Sonnet Combi, using Folbot sponsons. But the cost is prohibitive, once Folbot adds in another $250 to deliver to Canada. So since homemade sponsons were the alternative, I switched to the 17.5.

Was just wondering if anybody has any advice or experience to share in the construction of homemade sponsons. Right now we are considering gluing them but I'm concerned about air leaks. Am also considering buying a cheap-er pvc welder, a knock off of the Leister Triac for about 140 bucks, but I understand there's a lot of technique to pvc welding.

So I'm kind of dreading the process of building these sponsons. Any advice, experience or cautions that people want to share, I would appreciate it!

Will post some more as the build comes along (we're building two boats on my balcony - a 16 and the 17.5).

Lodeon

Re: Sonnet 17.5 - sponsons

Post by Lodeon »

I'd try to glue or weld the ends of these: http://tinyurl.com/7rlqdum

paddlesheep
faltbootemeister
Posts: 149
Joined: Tue Apr 08, 2008 1:37 am
Location: Vancouver BC

Re: Sonnet 17.5 - sponsons

Post by paddlesheep »

Interesting. Now that's got the hamster wheel in my head turning...

paddlesheep
faltbootemeister
Posts: 149
Joined: Tue Apr 08, 2008 1:37 am
Location: Vancouver BC

Re: Sonnet 17.5 - sponsons

Post by paddlesheep »

First experiments with heat sealable nylon are promising, so it looks like that's how we are going to build the sponsons.

Lodeon

Re: Sonnet 17.5 - sponsons

Post by Lodeon »

Pictures please... or write more in details. :)

paddlesheep
faltbootemeister
Posts: 149
Joined: Tue Apr 08, 2008 1:37 am
Location: Vancouver BC

Re: Sonnet 17.5 - sponsons

Post by paddlesheep »

As the build progresses I'm taking hundreds of photos and pages of notes, all to be coallated into a step by step build diary which will go up somewhere on the intertubes.

So...just a bit more patience :)

kg6gfq

Re: Sonnet 17.5 - sponsons

Post by kg6gfq »

I'd love to hear what worked (and what didn't) for making sponsons. I'm trying to follow Tom Yost's instructions for making sponsons with little success and lots of leaks.

Thanks!
-Darin

Lodeon

Re: Sonnet 17.5 - sponsons

Post by Lodeon »

Darin, let's wait for Tom to answer you. Anyway if I am not wrong, Tom already wrote (can't remember where) it's far better to buy the sponsons from here http://tinyurl.com/d6mmasu
or here http://tinyurl.com/cglz77z ...if i am not wrong, both should work well for the sonnet.
It's not recommended to build them by yourself. ;)
Last edited by Lodeon on Fri Jan 11, 2013 7:55 pm, edited 1 time in total.

paddlesheep
faltbootemeister
Posts: 149
Joined: Tue Apr 08, 2008 1:37 am
Location: Vancouver BC

Re: Sonnet 17.5 - sponsons

Post by paddlesheep »

Darin, unfortunately the project has stalled a bit owing to work and me getting sick. We wound up building four sponsons using the heat sealable nylon and homemade valves, as per Tom Yost's website. Mixed success. The nylon was trickier than expected, especially for such long lengths. Getting the length sealed properly on the first try was a challenge, most of the time we had to run the iron over the fabric several times. 3 out of the 4 hold air in my living room for about 48 hours, one more still needs repair around the valve.

To be honest, not sure if I trust the homemade sponsons. I'm thinking now I should have maybe gone with the three tube model and used folbot sponsons. We may go this route for the second boat, which is the standard Sonnet 16. Now that I've lost a ton of weight, I may go with a 16 too. (plus I bought a folbot cooper, so it's not so imperative to have a folder in the fleet anymore).

benalexander

Re: Sonnet 17.5 - sponsons

Post by benalexander »

I'd really like to hear how it went. I want to make a couple of Sonnets, but pretty much used up my kayak money on building a Sea Tour Double, PFDs, paddles, etc., so I'm trying to do it on the cheap. Used billboard material for the skin/sleeves, old aluminum tent poles for stringers, etc. In that spirit, buying $160 worth of balloons that you can, at least in theory, make from a few dollars of an old billboard seems silly.

Are homemade sponsons really that unreliable? Has anyone tried making them with lay-flat hose? That seems like it would work pretty well, since you don't have to seal long side seams, and 68 feet of the hose would still be much cheaper than falbot sponsons. It might even be possible to cut out some or all of the sleeve assembly, since the lay-flat is already very sturdy.

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