Boat Building Forum

Find advice on all aspects of building your own kayak, canoe or any lightweight boats

Re: Skin-on-Frame: Flotation bags
By:Bill Hamm
Date: 5/11/2011, 1:51 am
In Response To: Re: Skin-on-Frame: Flotation bags (Paul G. Jacobson)

: No. I haven't needed float bags in my canoe. The cheapest
: commercial roll-top dry bags work fine to keep my gear dry on
: trips. You could try something like that for floatbags in a SOF,
: but they are not going to fit as well as ones which are tailored
: to size.

: In his book on canvas covered boats George Putz suggests using
: pieces of precoated scrap material for patches. he suggests
: using rubber cement as a contact cement. The boy Scout design
: for folding kayaks uses contact cement for holding the canvas
: and plywood parts together. They report success with these
: materials being in the water, and on trips for a week. That
: should be more than enough time to get off the water!

: As for wrapping the boat to get a size: That is a pretty
: conventional sewing idea. They make human-shaped sewing
: mannequins for fitting dresses and blouses, and the process with
: boats is much simpler, although we want something smaller than
: the form (the boat) which the fabric is wrapped around. So wrap
: it, and sew it smaller.

: A small leak is fine. why do you ned them to be totally air tight.
: These are not balloons. if they have a slow leak and lose a
: gallon of air in an hour then should you capsize you have an
: hour to bail that last gallon out of your boat. If a perfect
: floatbag would keep 100 liters of water out of the boat, and a
: leaky one only keeps 96 out, then the difference is trivial.

: Put them in a bit slack and they will still displace water which
: gets into the boat. Inflating them to any level of pressure
: could cause them to expand too much on a hot day.

: If you have the material then this could be a fast way to make
: them. If you don't have heat seal nylon you can get a
: heat-fusible material like heat 'n' bond at Walmart or any
: sewing store. Platt Monfort uses that stuff for attaching the
: polyester material to the wood on his Geodesic Airolite boat
: designs. Works fine for him. Again, you can seal the polyester
: with whatever you used to seal the boat's skin. see
: www.gaboats.com for info on this.

: Good luck with your floatbags.

: PGJ

Heat 'n bond makes a fair temporary bond to fabric, it's not reliable long term and tends to let go over time. It's designed for sewing to hold seams together until it's sewn, was never intended to be a permanant bond.

Bill H.

Messages In This Thread

Skin-on-Frame: Flotation bags
Robert -- 5/5/2011, 3:55 pm
Re: Skin-on-Frame: Flotation bags
Ken Blanton -- 5/5/2011, 6:40 pm
Re: Skin-on-Frame: Flotation bags
john faas -- 5/5/2011, 10:26 pm
Re: Skin-on-Frame: Flotation bags
Ken Blanton -- 5/6/2011, 5:35 am
Re: Skin-on-Frame: Flotation bags
StephenHJ -- 5/6/2011, 1:01 pm
Re: Skin-on-Frame: Flotation bags
Paul G. Jacobson -- 5/7/2011, 5:35 pm
Re: Skin-on-Frame: Flotation bags
Jeff Horton -- 5/8/2011, 9:13 am
Re: Skin-on-Frame: Flotation bags
Bill Hamm -- 5/8/2011, 1:42 pm
Re: Skin-on-Frame: Flotation bags
Mike Savage -- 5/8/2011, 3:21 pm
Re: Skin-on-Frame: Flotation bags
Paul G. Jacobson -- 5/10/2011, 2:48 am
Re: Skin-on-Frame: Flotation bags *PIC*
Tom Yost -- 5/10/2011, 12:22 pm
Re: Skin-on-Frame: Flotation bags
Bill Hamm -- 5/11/2011, 1:51 am
Re: Skin-on-Frame: Flotation bags
Bill Hamm -- 5/11/2011, 1:53 am
Re: Skin-on-Frame: Flotation bags:small leak
Foster -- 5/11/2011, 11:24 am
Re: Skin-on-Frame: Flotation bags:small leak
Paul G. Jacobson -- 5/14/2011, 9:52 pm
Re: Skin-on-Frame: Flotation bags:small leak
Bill Hamm -- 5/15/2011, 12:32 am
Re: Skin-on-Frame: Flotation bags:small leak
Bill Hamm -- 5/15/2011, 12:34 am
Re: Skin-on-Frame: Flotation bags
Corona -- 5/11/2011, 12:32 pm