: Hey, I'm building a 14' great awk, and it is my first kayak, so I
: was wondering just how much fiberglass I am going to need

the three usual widths of cloth are 36", 44-45", and 60", with 44" fabric being pretty common. At a minimum you need 4 lengths of fabric to cover the 4 surfaces: Deck in and out, hull in and out. For a 15' boat (which is 5 yards) you would want at least 20 yards. Most people add on 10% because they want a bit extra for a cutting allowance. Can you get by with less? Absolutely. Look at the circumference of the hull, and also of the deck. most kayaks are in the realm of 24 inches in beam, and probably 38 to 42 inches around the hull at the widest spot (probably near the cockpit. The decks are not as deep, and there is no cloth over the cockpit, where the boat is widest, so you might see a measurement of 32 inches at the widest spot on the deck. If you are willing to use 44" cloth, do some careful cutting, and install your glass in pieces, you might be able to cover a boat with half the initial estimate. Or, in this case, 11 yards. The reason this is possible is that most kayaks come to a point at each end, and you don't need a lot of glass to cover them as you get closer to the ends, so you cut off a lot of overhanging cloth. it is perfectly good stuff, but odd shaped. Rejoice! Fortune favors you again. Some of those odd-shaped cutoffs will fit the odd shape of the deck or hull.

Here is the secret to getting the most out of your fiberglass cloth dollars: make 2 paper templates of the hull and 2 of the deck, and use these 4 templates to determine your glass cloth needs. A Sunday newspaper from any large city, and a roll of cheap masking tape or cellophane tape gives you all you need. Assemble pages from the newspaper into large sheets, lay two layers over the hull, use a few dabs of tape to hold them in place, then use a scissors to trim off any excess. You will want to keep about a 2 inch overhang. Cut through both sheets at the same time. label one "outside", and the other "inside". Do the same thing for the deck. With your deck you can run a big sheet from bow tostern, and go over the cockpit opening, or you can do sections: Bow to cockpit, cockpit to stern, and the thin strips that go around the sides of the cockpit. Now find a big space to lay out your papers.

If you haven't already done so, cut one of your deck pieces in half, right through the cockpit, going from gunwale to gunwale. lay this on the ground with the freshly cut edge at one end. Touching the bow or stern point of this piece will be a full-sized outside hull piece. Following that , point to point, goes the second half of your deck template. what you have in front of you will look like a double hourglass. as you look along the length of this figure, you'll notice that on the left side, and also on the right side, are cut-out areas which are roughly the length of your kayak, and roughly half the width. There will be two like this on the left, and a mirror image of those two on the right side. You'll use a left and a right piece for the inside of the hull, with the seam running down the center of the boat, where the doubled layer will add a bit of strength. And the last pair of "halves" lines the inside of the deck in the same manner. Depending on the actual curvature of the boat, you may need to space the outer fabric pieces a few feet apart, to get big enough cutoffs for the inside fabric--but if you are working with expensive fabric this will get you the best fit.

: Also, what thickness is best? I probably won't be going any more
: extreme than some day trips.

4-ounce cloth is perfectly fine. Older plans used to call for 6 ounce cloth, but over he years builders have found that this was more than necessary. The thinner cloth uses less resin, which can save money, and give a lighter boat.
en
At a minimum you want to use about the same *weight* of cloth and resin in order to get the most efficient balance of cost, strength and weight. Since the resin conveniently weighs about the same as its liquid volume, for a square yard of 4-ounce glass cloth you would use at least 4 ounces of mixed resin. That is the total amount for all three coats of resin. This is practically impossible for an amateur to do by hand. Usually we use a lot more resin. and then we sand off some of the excess. In the best-case-scenario of a professional 'glassing job done with vacuum bagging equipment this lean of a mixture will give strong results, but the surface will not be as smooth as one would wish.

Once the glass is bonded to the hull with the wet-out coat of epoxy the resin will harden around each glass fiber, and "telegraph" the pattern of the weave. The surface will appear as uneven as the original woven texture of the glass cloth. It is our usual parctice to put on another coat or two of epoxy in the hope that we can fill in the texture and get a mirror-smooth surface. a`tually, all we do is build up the thickness of the epoxy coating. To get it smooth we come back once the plastic has hardened and sand away the high spots to get that desirable smooth surface. All that extra resin adds absolutely nothing to the strength of the boat, but it adds weight and cost. It does give a thicker plastic coating which is slightly (very, very slightly, mind you) more resistant to dents and dings. And it makes the boat look pretty and it reduces some of the drag, so the boat paddles a teensy bit easier.

: And on a slightly similar note, howmuch epoxy will I need

If you are using 4-ounce glass and use a single layer on all surfaces, you should be able to get by with a mixed gallon to gallon and a half. If the brand of resin you use is mixed at a ratio of one part resin to one part hardener then you'll need 1/2 gallon of each part, and some care. If your epoxy goes for a 1:@ mix, then you'll need a gallon of resin and 1/2 gallon of hardener. This is 50% more than the first case (a total of 1.5 gallons mixed volume) so you have some room for sloppy work, and margin for mixing mistakes.

If you use 6 ounce glass you'll use 50% more resin. The glass is 50% thicker than 4-ounce glass, and just as thirsty.

If you use a double layer of glass over the high-impact area of the hull bottom, then you'll use about 8 to 12 ounces more resin. You can put this layer of glass on last, and if you are running short on resin you can even eliminate it, or install it a year or more later.

Ballpark figures: Double the weight of your glass cloth to get the volume of your resin. If you are using 22 yards of 44" fabric (which is about 1.25 yards wide) your cloth will weigh 5 ounces for each running yard. That is 110 ounces. You get 128 ounces in a gallon, so figuring that you'll cut away maybe 30 percent of the fabric, and not need to coat that, your bare minimum would be about 85 ounces. With gallon, and some care, you'll be all set. A gallon and a half gives you more than twice your minimum, and enough to cover many mistakes!

Extra resin is a good thing for other projects--you'll be amazed at how you find projects to glue with this stuff! You can use it for making repairs to dings and dents at the end of each paddling season. A patch may take an ounce or two. Pour your excess resin into smaller bottles and it will keep for years at room temperature.

Keep lots of plastic gloves areound, and change them frequently as they get sticky fast.

And have a good time. Hope this helps.

PGJ

Best tip for last: Check at thayercraft.com for their special on 3.2 ounce glass cloth. It is a suitable replacement for 4 ounce cloth for you needs. It is so inexpensive that buying a long bolt, with more than you need, is still cheaper than buying exactly what you need from most other sources. Their #1678 deal is 50 yards for $60 (that is $1.17 a yard !) and it includes shipping in the US. You'll have enough for sloppy cutting and still be able to make two kayaks from it. With care, you could do or maybe 4. Or, put it on double thick and have a very strong, very heavy boat. Get afriend interested in building and sell them half. you'll both have more than enough.