Adding flotation

I am looking for ideas and assistance on adding flotaion to my sundance. I was surprised this weekend when my boat got swamped and settled below the waterline (but didn’t sink). Towing it to shore was not the best time I ever had. Any suggestions as to how and what to use for a permanent solution? Much thanks.


If performance matters

– Last Updated: Sep-17-04 2:47 PM EST –

float bags are the way to go. They are much more lightweight. Sea kayaker published a great DIY article on making float bags. Float bags must fit the boat well and be secured to be effective.

Others will recommend foam noodles (heavier per cubic inch and not easy to secure) blowing marine foam into the boat (expensive with the right density of foam and heavy).

Flotation Bags
made by NRS, Voyager, Harmony and other companies. You can also use beach balls, capped off plastic milk jugs or soda bottles. If your wife is upset about your kayak purpose, inflated inflatable sex dolls serve a dual purpose ( Flotation and… well you figure it out)

Sundance flotation
I Have 2 Sundance 9.5’s. I use flotation bags in the stern. You need pretty big ones to fill in the space. I have found that most of “split” bags are too small, so I would reccommend two full size bags, one for each side of the foam pillar. I found some good deals on ebay.

I am also debating adding etha foam to the bow on either side of the standard foam. These boats hold ALOT of water when swamped!!!

Get a bag for the bow, too
Have you swamped your boat with just the stern floatation? It’ll end up in a classic “Cleopatra’s Needle” position, with the bow pointing straight down. This is an impossible situation for self rescue and a very difficult one for assisted rescue.

Ethafoam pillars are no substitute for a float bag. They simply don’t add enough buoyancy.

I have swamped it with just the stern bags and didn’t have that problem. The boat stayed level on/partly under the water. I do want to add the foam in front, I just think it will be able to be secured in place better than float bags, since theres nothing to attach the bags to in front of the foot pegs.

Eathafoam can be very dense (small cells for support structures like NRS sells) or not so dense (pool noodle or packing foam). The softer and more pliable the foam the more bouyancy per volume and less weight also. Bob

Has anyone made their own floatbags? I don’t mean using pool noodles…I mean an actual float bag. I checked Sea Kayaker to see if they had the DIY article still available and they don’t (it appeared in their June 2002 issue).

truck innertube

Making your own float bags
I made some float bags for my folder recently. I used Coverlight ($9 for a yard, 60" wide) sold by Mauritzon Inc. This is a PVC-coated polyester fabric that I already had on hand. It is glued with HH-66, which is like rubber cement on steroids. I cut the Coverlight to shape, sanded a bit of PVC tube and HH-66 glued that on, folded and glued up the bag and then got a little rubber plug at the hardware store for the end of the tube. Works great!

Heat-seal nylon is another way to go, but I think the material is more expensive and I don’t know how to attach a tube to it.


beach balls?
I like that idea…reasonably priced and easy enough to find. Dumb question time: If I get a couple of small ones and semi-blow-them-up and stuff them up the bow and the stern, will they ‘mold’ enough to the space in there to be worth it or would just getting funnel-shaped air bags be a better bet?

Were you sitting in the swamped boat?

– Last Updated: Sep-19-04 12:02 PM EST –

If not, then you really can't tell if the floatation is adequate. A small amount of trapped air in the bow can keep it floating until you put some weight in it, at which point the bow will submerge, the air will escape and you end up with a Cleopatra's Needle.

Float bags are easy to secure in the front. You just need to install a retaining cord between the foot peg rails. They don't need to be secured at the front, just prevented from backing out.

Yeah, it’s pretty easy.
You need heat seal nylon fabric, vinyl tubing from the hardware store and some Aqualseal, GOOP or Lexel. The valves are available if you want them, but plugs work too.

Fabric prices
I got in on a group buy through Shawn Baker for $3.00/yard. Even at regular prices, HS Nylon isn’t any more expensive than Coverlight. Coverlight is probably more durable, but considerably heavier.

Thanks for the input
Thanks for all the suggestions and you’ve given me some great ideas…but tsunamichuck gets points for the most “creative” suggestion!

You can say that again…the 12 footer just adds that much more water and a hump load of bailing. I HAVE to get float bags! Thanks.

What about polyuretahne foam
Has anyone tried polyurethane foam? I know it can be pricy but I have some on hand and it would be a more permanent solution. Any thoughts? Thanks.

Foam blocks or expanding foam?

– Last Updated: Sep-22-04 10:27 AM EST –

If you're thinking of carving foam blocks to fit and the polyurethane foam is closed cell, it will work fine. I wouldn't recommend using expanding foam of any type.

Easy To Do…

– Last Updated: Sep-22-04 11:35 AM EST –

I've gone through ten yards of heat sealable already, and about another 5 yards in a 20 yard roll. Is it worth it to go through the process? Depends. I've got like 10 boats at the last count. I have plans to build two more this winter. I got drybags to make with scraps. I got cockpit covers...

Anyway, It's far cheaper for me to make my own stuff with heat sealable nylon then to buy them for the number of boats I have. I think when I last bought float bags from NRS for my capelookout, it was like 50 plus dollars. That's what I paid for on 20 yards of heat sealable nylon. My float bags get custom fitted to each of the boats I am using it for.


Thanks but I got a deal…
…on pool floats, the kind that keep heavy pool covers out of the water during the fall and winter. The local Job Lot store has these things in ten different sizes, some with grommets, some which need them, but they are inexpensive and sturdy!

These not custom fit but I only have two boats to outfit…