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Yes, I'd trust a boat with NO inside glass
By:Paul G. Jacobson
Date: 10/11/2007, 1:01 pm
In Response To: Re: makes no sense (HenkA)

: Sure but would you trust a strip boat without interior glass?

Of course I would. There are plenty around which have seen all the abuse that decades of campers can give them.

Retyurn with us now to those thrilling days of yesteryear. From out of the past comes the thrilling designs of man named Rushton.

According to Teed Moores's book "Canoecraft', Rushton used 2-inch-wide strips -- wider than we do -- and overlapped them a bit. (this was called lapstrake construction. The strips were called strakes, and they were overlapped) No glue held them together. Rather he used copper nails which were dirven through and "clenched" (or clinched) by bending the pointed end of the nail back into the wood. If you have a hard time imagining how this is done, take an office stapler and look at the bottom part, or "anvil" which bends over the leg of the staple after it passes through the papers you want to fasten together.

The overlapping strips were secured to interior ribs, made of steam-bent wood. These ribs provided the necessary internal support for the boat.

Rushton also used a thick varnish to seal all the joints and seams. It probably worked like glue.

Rushton's boats were durable, and light. By avoiding a few pounds of glass and an equal amount of resin he could save 5 to 8 pounds over a similar boat made with "modern" construction. His Wee Lassie design has been adapted and copied by several companies and is still popular with people who want a small, easily carried boat. (Heck, now that I think of it, I already have forms cut for one in my basement) People who try can build one at about 17 or 18 pounds, but 20 is more common. The ones Rushton built were 12 to 15 pounds. In addition,Rushton's appear to have slightly higher sidewalls for more carrying capacity or freeboard. Put those same higher sidewalls on a 'glass covered boat and you'll simply increase the weight by a few more ounces.

A look at the front cover of Ted Moores "canoecraft will show the difference in the interior looks of a boat built with glass on the inside, and one built with ribs.

As for homebuilding such boats: It is a more involved prospect, but not impossible. The key to such building is that you first construct a full size "mold" which has indentations where the ribs will be. Those indentations are then lined with strips of steel to clench the copper nails. These boat molds are timeconsuming to make, and heavier than our strongbacks with forms and boat attached --so they are not easily moved around. If you are going to produce several boats in the same shape, then once you have a mold, you can indeed create a small assembly line in your back yard and knock out another boat every few days.

At Canoecopia in 2006 I saw three exhibitors who had canoe molds. One was an old one (still used, but mostly jsut for show), but the other two had been made in the past few years, and were being used to make canoes with interior ribs. The process was being demonstrated (slowly--one or two strips a day)by one of the exhibitors.

Making the molds is similar to building with wood strips, but you use "strips" that are 3/4 inches thick, on forms spaced 4 to 6 inches apart, and you don't need to get the strips to fit tightly together. A router cuts recesses for the steel clenching plates directly over each building form. The clenching plates themselves you can make those from 1-inch-wide, 16-gauge mild-steel strips. Clark-Craft (www.Clarkcraft.com) sells the copper nails for this.

The hull can be glassed on the outside, or finished with varnish. Of course the popular covering for years was painted canvas.

Kayaks with ribs? sure. Make the hull like you would make a ribbed canoe hull, then use deck beams to support the strips for the deck.

More modern designs? Kayaks instead of canoes or covered canoes? Sure. Go with wood chines instead of fillets in your plywood boats, and use an occasional bulkhead-type frame for cross bracing. With marine plywood the wood just needs to be painted or varnished. Or, put a plywood skin on a SOF design. You can use 1/8th inch or 3 mm ply for this as the structural strength is in the frame.

So, you don't really need glass reinforcement on the inside of any boat, as long as you provide someother structural replacement that does the same job.

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