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Re: S&G: S & G less durable than strip-built
By:Paul G. Jacobson
Date: 10/3/2007, 2:44 pm
In Response To: S&G: S & G less durable than strip-built (john faas)

: . . . Builder . . . said S & G don't hold up well--failing at the
: joints between panels, compared to strip built. . .
: So any comments on durability of S & G

"Dynamite" Payson wrote on book on "Instant Boats" which was an inspiration and guide for many people building with the method we now know as "Stitch and Glue". The techniques worked for a lot of boats--including those mauch larger than canoes and kayaks. When Payson's book first came out the only resin available was polyester, so that was what was used. Years later we know that epoxy bonds a bit better. The older methods of stitch and glue used two or three layers of fiberglass tape only over the seams. The rest of the wood was then simply painted.

Strip-built boats must have the entire hulls sheathed with fiberglass on the inside and outside. There is a larger surface area for the bonding of the glass, and you don't have the edges of the seams under the waterline.

Well, I know that paint "breathes" a little, and moisture can invade the wood over time. That can help to weaken the bond between the paint, the wood, and the fiberglass tape. So, it is easy for me to understand your friend's viewpoint.

People who build with plywood may use marine plywood, or they may use common exterior-glued panels. Some may have even used plywood which was designed for interior use. If someone used inferior materials I wouldn't be surprised if their boat lasted a shorter time than one built with the right components.

Being built with plywood--an essentially flat material--many S&G designs have large flat areas. Probably some of the flat areas on some S&G designs could have benefitted from having some internal ribs or other supports--particularly when they are used with heavy laods. That tend to be a design issue which is either solved over time, or never solved. It depends on how much feedack the designer gets. Now a days structural engineering (handled by the computer) usually comes into play when a design is drawn up. The computers know how much a plywood panel of a given thickness can flex under a load, and maximum loads or extra bracing is specified.

Probably a lot of older stitch and glue boats did come to an early end. However, they were built inexpensively and easily, so the owners probably got their money's worth.

If you are building a modern stitch and glue design, and you sheathe the entire outside with glass, you essentially have a solid fiberglass tub with a wood boat inside it. If you coat the inside of the boat with two coats of epoxy to encapsulate the wood, or put a layer of glass on the inside, I can't see any reason why that boat should not last as long as a stripper.

Just some thoughts on the matter.

PGJ

Messages In This Thread

S&G: S & G less durable than strip-built
john faas -- 10/3/2007, 1:58 pm
makes no sense
LeeG -- 10/9/2007, 8:20 am
Re: makes no sense
HenkA -- 10/9/2007, 10:47 pm
Yes, I'd trust a boat with NO inside glass
Paul G. Jacobson -- 10/11/2007, 1:01 pm
Re: Yes, I'd trust a boat with NO inside glass
Bryan Hansel -- 10/11/2007, 7:18 pm
Re: Yes, I'd trust a boat with NO inside glass
Bill Hamm -- 10/11/2007, 8:00 pm
Re: Yes, I'd trust a boat with NO inside glass *LINK* *Pic*
Dan Caouette (CSFW) -- 10/12/2007, 8:02 am
Re: Yes, I'd trust a boat with NO inside glass
Bill Hamm -- 10/12/2007, 8:17 am
I'd like a side of ribs with a glass of resin
Paul G. Jacobson -- 10/12/2007, 11:05 am
Re: I'd like a side of ribs with a glass of resin
Bill Hamm -- 10/12/2007, 3:52 pm
Re: I'd like a side of ribs with a glass of resin
Mike Savage -- 10/12/2007, 2:04 pm
Re: I'd like a side of ribs with a glass of resin
Dan Caouette (CSFW) -- 10/12/2007, 11:25 am
Re: I'd like a side of ribs with a glass of resin
Paul G. Jacobson -- 10/12/2007, 11:57 am
Re: I'd like a side of ribs with a glass of resin
Dan Caouette (CSFW) -- 10/12/2007, 12:18 pm
Re: Yes, I'd trust a boat with NO inside glass
Dan Caouette (CSFW) -- 10/12/2007, 10:36 am
fix up your Pal
Paul G. Jacobson -- 10/12/2007, 11:47 am
Re: fix up your Pal
Dan Caouette (CSFW) -- 10/12/2007, 12:16 pm
Re: fix up your Pal
Bill Hamm -- 10/12/2007, 3:46 pm
Re: fix up your Pal
Dan Caouette (CSFW) -- 10/14/2007, 8:19 am
Re: fix up your Pal
Paul G. Jacobson -- 10/12/2007, 1:04 pm
Re: Yes, I'd trust a boat with NO inside glass
TOM RAYMOND -- 10/11/2007, 6:00 pm
Re: Yes, I'd trust a boat with NO inside glass
Bill Hamm -- 10/11/2007, 5:02 pm
Re: Yes, I'd trust a boat with NO inside glass
John Monroe -- 10/13/2007, 6:38 am
Re: Yes, I'd trust a boat with NO inside glass
Bill Hamm -- 10/13/2007, 7:17 am
Re: Yes, I'd trust a boat with NO inside glass
Paul G. Jacobson -- 10/11/2007, 6:48 pm
Re: Yes, I'd trust a boat with NO inside glass
Bill Hamm -- 10/11/2007, 7:58 pm
Re: makes no sense
Bryan Hansel -- 10/10/2007, 12:32 pm
Re: makes no sense
Robert N Pruden -- 10/10/2007, 8:12 pm
Re: makes no sense
TOM RAYMOND -- 10/11/2007, 11:41 am
Re: makes no sense
Bill Hamm -- 10/11/2007, 2:51 am
re. ten pounds less
LeeG -- 10/10/2007, 12:55 pm
Re: makes no sense
Bill Hamm -- 10/10/2007, 1:38 am
Re: makes no sense
HenkA -- 10/10/2007, 10:39 pm
Re: makes no sense
Bill Hamm -- 10/11/2007, 2:48 am
Re: makes no sense
HenkA -- 10/11/2007, 3:46 pm
Re: makes no sense
Bill Hamm -- 10/11/2007, 2:49 am
Re: S&G: S & G less durable than strip-built
HenkA -- 10/4/2007, 8:25 pm
Re: S&G: S & G less durable than strip-built
HenkA -- 10/4/2007, 10:44 pm
Re: S&G: (Link to thread: Which gives stronger boa *LINK*
HenkA -- 10/4/2007, 10:34 pm
Re: S&G: (Link to thread: try again *LINK*
HenkA -- 10/4/2007, 10:55 pm
Two links to tests of strip & S&G
Glen Smith -- 10/4/2007, 8:54 pm
Re: Two links to tests of strip & S&G
Robert N Pruden -- 10/4/2007, 9:58 pm
Re: S&G: S & G less durable than strip-built
Bill Hamm -- 10/4/2007, 1:30 am
Re: S&G: S & G less durable than strip-built
vk1nf -- 10/3/2007, 9:44 pm
Re: S&G: S & G less durable than strip-built
Aaron -- 10/3/2007, 8:41 pm
Re: S&G: S & G less durable than strip-built
Scott Baxter -- 10/3/2007, 7:49 pm
Disagree!
Robert N Pruden -- 10/3/2007, 6:43 pm
Re: S&G: S & G less durable than strip-built
Charlie -- 10/3/2007, 5:39 pm
Re: S&G: S & G less durable than strip-built
Paul G. Jacobson -- 10/3/2007, 2:44 pm
Re: S&G: S & G less durable than strip-built
Robert N Pruden -- 10/3/2007, 6:49 pm
durability not the issue. Think "ability" instead
Paul G. Jacobson -- 10/4/2007, 9:12 am
Re: durability not the issue. Think "ability" inst
Robert N Pruden -- 10/4/2007, 6:30 pm
Only one job? You'll go mad!!! *NM*
TOM RAYMOND -- 10/4/2007, 6:47 pm
Robert is gonna start writing his books
Robert N Pruden -- 10/4/2007, 7:06 pm
Re: Robert is gonna start writing his books
Ken Sutheland -- 10/6/2007, 6:24 pm
Re: S&G: S & G less durable than strip-built
Bryan Hansel -- 10/3/2007, 2:17 pm