building thoughts (long)

Posted by DaveW on Oct 31, 2004

Having just completed my third S&G boat, I thought I'd post a few of my thoughts on different building methods.

Sheer clamps. I like them. They help the hull hold its shape during the building process. They give you something to drive screws into when you mount your deck rigging. I don't think they add much, if any, weight compared to a mixture of thickened epoxy. It is a lot easier to glue on a shear clamp than it is to apply thickened epoxy and fiberglass tape to a joint 8' away from where your head and hands are, especially when your head and hands are inside the boat. Maybe some midgets can get their head and hands in through the hatches to work on the ends, but I can't. Finally, I have yet to get thickened epoxy in my hair and on my arms from gluing on shear clamps.

Scarf joints. I know that most builders find them relatively easy to use. I hate them, but I still use them becaue it's the only way I know. I have yet to get all the scarf joints on a hull to work out perfectly. My solution on my latest boat was to decide in advance that I was going to paint the hull. The joints that didn't turn out quite right got sanded flush and the area was levelled out with fairing compound or high build primer. No one else knows, and I got a great deal of satisfaction from one-upping the cursed scarf joint fairies. I will be spending some time this winter experimenting with other methods.

Deck and hull glassing. I've gone to complete glassing of the hull and deck both inside and out, and I don't tape the chine and keel seams. On my last boat I used 4 oz. S-glass on the inside of the boat to save weight. I was tempted to use it on the outside of the deck, but couldn't work up the nerve.

Deck reinforcement. I used a strip of 12" wide carbon fiber to reinforce the deck behind the cockpit. That was recommended by the designer of my latest boat and seems to add a fair bit of stiffness to that area the deck. I'm sure there are other methods that work just as well, but that one worked well for me.

Carbon fiber and s-glass. Carbon fiber is easy to work with, and so is 4-oz s-glass. I didn't notice much difference in the clarity of the 4 oz s-glass as compared to the 6 oz e-glass, but I was only using it on areas that would not be visible, so I wasn't paying that much attention. The one area where I did notice a difference was where I used a double layer of 4 oz s-glass.

System 3 Silvertip vs. MAS. I've had good luck with both. System 3 sets up a bit faster and is a bit thicker. I used MAS when I wanted a longer working time. The main area where this was a concern was when I filleted and glassed the inside of the hull. I'm relatively slow when it comes to doing the fillets, and I like to lay the glass over soft fillets, so the longer working time of the MAS was a benefit. I used MAS for the fillets and System 3 for the glass.

Paints. I've used Brightsides on one boat and Toplac on one boat. Toplac covers better, which translates to fewer coats of paint, but doesn't come in as many colors.

Varnish. I've used Captains and Flagship. Both are easy to apply and give a nice finish. I'll probably continue to use Flagship because of the higher UV protection it provides.

Squeegee vs. roller for applying epoxy. I've always used a roller, but may try a squeegee in the future. I've had a few areas on a couple of boats where I didn't get quite enough epoxy on with the roller. This is a problem with my technique, not with the roller itself, but I'm interested in seeing if I do better with a squeegee. Otherwise I like the roller for ease and consistency of application. Incidentally, I use the white foam 4" rollers that you can get at Lowe's and Home Depot. They work fine, but they soak up a lot more epoxy than the traditional epoxy rollers. If you figure that you are wasting one full squirt of epoxy each time you use a fresh roller, and you are applying 3-4 coats of epoxy on the hull, the same on the deck, and one or two coats on the hull and the underside of the deck, that's 8-12 squirts of stuff. I use them because I can drive five minutes and pick up more when I need them, but I'd probably be better off using the more traditional epoxy-application rollers.

Latex vs. vinyl gloves. I bought some vinyl gloves by accident this time around. I like them better than the latex gloves. They are tougher, easier to slip on, and don't make my hands itch.

Flush vs. raised hatches. I like the flush hatches. Nick Schade's book shows one method of doing them Vaclav from One Ocean Kayaks shows something slightly different. Ross Leidy (Blue Heron Kayaks) shows an internal holddown system that works really well. The only thing to bear in mind with Ross's method is that you may have to experiment with the tension on the internal bungies to get them tight enough. There are other methods that apparently work well, but this one is the only one that I've tried.

Rear bulkhead location. I like doing the rear bulkhead flush with the rear of the cockpit with the bottom angled slightly into the cockpit to make it easier to empty water from the cockpit. You won't be able to use the bulkhead that comes with the kit, and it takes a little more time and effort, but I like it. The backband hardware can be attached to the bulkhead instead of to the underside of the deck.

End pours. I don't know why folks get so excited over whether or not to do an end pour. I've switched to putting in a dam early in the building process, then dumping excess epoxy (sometimes thickened, sometimes not) into the ends while I'm building. I'm forever mixing up too much epoxy and it's nice to be able to do something with a little bit of the extra. However, it's just as easy to do an end pour after the hull and deck are joined.

Strongbacks and building forms. I did two boats without them and have done one boat with them. Both methods work. With the strongback and forms, you align everything before you start building and don't have to fuss with it much during the building process. Without them, you'll be doing your alignment during the building process. The one area where I would advise using a strongback is if you are planning on doing a hybrid boat (plywood hull and stripped deck). You'll be putting enough pressure on the boat when you are fairing the deck that it is nice to have the boat anchored in place.

For what it's worth . . .