Fiberglass Seal Coat

We fretted over fiberglassing the hull so much, we put off beginning with this step for weeks.  We read and reread our instructions from Glen-L, Ken Hankinson Fiberglass Boatbuilding book, and anything else we could find.  We went over scenarios and thought of terrible things that could go wrong.  We thought it would be so harrowing and difficult, that in the end, it was a bit of letdown.

Heres where we left the boat last time.  Filled, shimmed, routed, sanded lovingly.  Lawrence came by a couple times and asked, "What are you building, a boat or a piece of fine furniture?"

Before we started the day, we had to wipe the whole boat down and make sure there was no sawdust, grease, debris, or anything anywhere.

But really, this was just the seal coat, the first of four or five coats wed put on the hull.  We wouldnt even get out the glass cloth until the next coat.

And now a quick primer on fiberglass:  Fiberglass is a composite laminate material.  The layer(s) of spun glass cloth or mat embedded in a matrix of polyester or epoxy resin are what gives it strength.

In some boats where the hull derives its strength from the fiberglass, it is typical to use alternating layers of mat (a loosely woven nest of randomly aligned spun glass) and glass cloth.  In our boat, the fiberglass covering on the plywood hull served only the purpose of keeping it watertight and creating a durable wear-resistant maintenance-free surface.  So we had only to put one layer of glass cloth between several layers of epoxy.

There are many methods of applying fiberglass to a boat hull, but they break down to the so-called wet and dry methods.  "Wet" means the fiberglass cloth (or mat) is laid over a just applied layer of resin and then "wet out" with more resin on top.  This sounded hectic. We imagined laying cloth over a wet sticky layer of resin and fighting wrinkles and having the cloth misaligned and pulling our hair out and getting sticky head to foot.

We were relieved to discover in our Glen-L instructions that they recommended the dry method.  "Dry" means simply that the first coat is rolled out without the cloth and allowed to set.  Then the cloth layer is laid out over this dry layer and more resin on top of that to wet it out.  This allows us to carefully align the cloth without the stress of either sticky goo or the ticking clock.

In this first seal coat, all we were doing was covering the hull with epoxy.  Kai mixed up big batches of epoxy and put them in paint trays for me to roll out with a dense foam roller.

Then Kai came around with extra resin and touched up spots Id hit too lightly and brushed down any air bubbles.  Because we werent mixing the resin with filler, it had a longer pot-life and so didnt tend to kick off early, even though we were mixing it in larger quantities.

The result was beautiful, though vaguely reminiscent of a horribly outdated style of 70s handmade varnished pine bedroom furniture.

Though it was a hot day in the barnyard, we were feeling pretty good about our work and the results.

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Those Troublesome Skegs Part the First

When we built punk rafts and floated several big rivers, we powered the rafts with canoe paddles and our own arms.  Though the big innertubes that floated the rafts provided so much flotation, they drew no more than a few inches of water, it was still like pushing a truck.  After a long day of avoiding Swirlies (eddies) and River Sharks (snags), we were exhausted.

Since the raft had no keel or centerboard, it had nothing to provide lateral stability.  So when we were going forward, we had to synchronize our rowing or else wed be zigging and zagging all over the water, which we did plenty of anyway.

As an aside, having no keel did have one advantage:  We could rotate on a dime. So for example, avoiding an object in the water dead ahead, the Caller might call, "Okay, give me one easy backward stroke," while paddling forward herself to pivot the raft toward the hazard.  Then shed call, "Okay, now give me three strong backward strokes," to put the raft out of the way of the snag. Facing the hazard forward thusly, we could always push off if we hadnt rowed fast or strong enough.

In short, it was a big pain.  And exhausting if we had to row any distance, for instance in still water.

The plans for the shantyboat have long skegs (sorta like double keels) that run the length of the bottom of the hull. This gives the boat lateral stability when it is powered and keeps it from skipping all over the water when the boat is turned.

While it really didnt seem like a big deal to make and install the skegs on the finished hull, it turned out to be a bit of a long process.  Heres why:

1. The skegs had to be made out of a rot resistant wood that turned out to be hard to find in the lengths I needed.
2. I ended up having to splice board together to make adequate lengths.
3. They had to be bolted through the beautiful hull Id just finished making watertight, and I was scared.
4. I screwed up several times and had to redo stuff.
5. I had inadequate tools for some of this work.

It sounds like Im making excuses, but it feels more like:  "Haha, look how dumb I am, yet I still got it done."

The plans called for any of a variety of woods, none of which the local lumber yard had in anything approaching the lengths I needed.  White Oak, Yellow Cedar, Port Orford Cedar, a few other ones that are found on the East Coast. Ideally, I was looking for 16 foot lengths. But these are increasingly rare hardwoods that simply dont come in those lengths.

I found a specialty hardwood vendor only a half hour away. They had the Port Orford Cedar and what they called Alaskan Yellow Cedar. Neither of these are actually cedar, but are cypress. For you botany nerds, Port Orford cedar is officially known as Lawson cedar or Chamaecyparis lawsoniana. Alaskan yellow cedar is Cupressus nootkatensis.

Of those, the longest they had was 14 foot lengths. A conversation with the hardwood dealer goes like this:

"Can you get either of these trees in sixteen foot lengths?"

"We get what we get."

"I mean do you ever get 16 foot lengths? Can you order that length?"

"We get what they bring us."

O-kay.  That didnt sound too hopeful.  I knew if I had to, I could splice a longer length together.  There was lots of frantic maths at the lumberyard trying to see what lengths gave me the most efficient use of wood.  While still expensive, the Port Orford cedar was half the price of yellow cedar, so that decided it.

This was expensive wood, so I wanted to make sure I got the best use out of it. I had to use the cedar for the bottom skegs, the fore skegs, the trim boards along the bottom side, and the edge boards all around the top edge. So I created a cut plan so that every bit of the wood was put to use.

Then I spent days cutting and ripping and making lots of sawdust, sure that every cut I made was going to render this expensive piece of wood unusable.

Next well talk about the splice that turned four shorter pieces of wood into two long 16 foot skegs.

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