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Re: how much cloth?
By:Paul G. Jacobson
Date: 1/24/2001, 10:42 pm
In Response To: Re: how much cloth? (sage)

: The Syntex is 50" wide.

: Thanks sage.

In general:

If the hull is completed: Measure the circumference of the hull, from sheer line on the left to sheer line on the right, at the widest part of the hull -- probably near the cockpit. With a canoe you would measure from gunwale to gunwale.

On your boat it should be somewhere in the 35 to 45 inch range.

If the hull is not completed, take these measurements off of your plans, offsets, or measure the biggest frame form.

Whatever number you get is the minimum width for fabric that you can use without having to add pieces here and there to cover.

In your case you'll be just fine with 50 inch wide fabric. With some narrow kayaks people can use 36 inch wide cloth, and maybe save a few dollars.

Once you know this, the simplest way is to just measure the lentgh of your boat in whole yards, (round up) and multiply this by the number of layers of fabric you wish to apply.

Let's assume you are putting one layer on the inside and one layer on the outside of the hull, and the boat is 17 feet long. That is 5 2/3 yards long, so we round up to 6 yards, and multiply by 2 to get 12 yards.

Now measure the outside circumference of your deck, from sheer to sheer. On your boat this is probably 25 to 35 inches. also measure in front and behind the cockpit.

The simple way here is to just buy the same amount as you did for the hull. But that will give you a lot of excess material, as the deck is nowhere near as wide. What you can do is apply the glass to the deck in 4 pieces. Two for in front of the cockpit ( that would be inside and outside), and two for in back. If the general shape of the kayak is a long diamond, then each of these 4 pieces will be roughly a triangle. You can easily cut two of these pieces side by side from 50 inch wide cloth if you cut one with the base of this triangle towards you, and the other with the point of the triagle towards you. So, for covering the deck with one layer on the outside and one on the inside, if you use 4 pieces of cloth, you'll only need to buy 6 yards of fabric.

Doing it this way you will originally get a small bump where the glass cloth overlaps, but this is easily smoothed by sanding, and in a narrow spot, along side the cockpit. In fact, if you plan on having a long overlap -- say the entire length of the cockpit -- , you can get a double layer of fabric running there, reinforcing that area where you will put all your weight when you enter and exit.

If you want to do the hull in four pieces instead of two you can do it like the deck, with an overlap under the cockpit, or, you can cut the fabric for the exterior of the hull in one football-shaped piece and do the interior from the four "triangles" that are left in the corners of the fabric. If you do this you will have a bit more sanding on the interior. Either way, you can buy about 7 yards of fabric for the hull instead of the 12 previously mentioned.

Finally, you can sometimes economize even further by using the scraps from the hull for doing the interior of the deck. No one notices the seams there, and it is easy to sand down any overlaps that might be visible.

OK, so for your boat, you can get 12 yards for the hull and 12 for the deck ( total 24 yards) and have an easy time cutting it, and some excess cloth. Or, you can get 12 yards for the hull and 6 for the deck (18 yards) and piece together the inside of the deck. Or, you can get 6 yards of cloth and do some preliminary cutting, and some additional sanding and try to cover the hull and deck with lots of pieces.

If you use your measurements of the hull and deck at the widest point, and also measure the hull and dec at the narrowest points (bow and stern) you can cut out a scale model of the boat's covering from a few pages of yesterday's newspaper. Use a scale of 12:1, where a foot of real boat equals an inch in your model. (If you are building to metric standards, use 10:1, where a meter equals 10 cm on your model.)

You can make a model of the fabric by cutting 4 inch wide strips from the newsprint, and taping them together to get whatever length you need. this would be the equivalent of 48 inch wide fabric, but that just gives you a little margin of safety when you get to cutting the real stuff.

Lay out your templates on the paper strip, and arrange them to fit in the shortest length of "fabric" You can cut the templates into pieces if you wish -- but label them so you are sure you don't miss a part. Don't let the pieces touch. You should have a bit of room around each piece -- again, a safety margin.

After all of this, order an extra yard of fabric.

HOpe this helps.

PGJ

Hope this helps.

Messages In This Thread

how much cloth?
sage -- 1/24/2001, 1:44 pm
Re: how much cloth?
sage -- 1/24/2001, 1:48 pm
Re: how much cloth?
Paul G. Jacobson -- 1/24/2001, 10:42 pm
Re: how much cloth?
sage -- 1/25/2001, 1:47 am