Day 23


Here’s the entirety of the instructions in the Book of the Oxford Shell about how to glass the hull:

Cover the outside of the hull with fiberglass cloth. Drape the cloth over the entire hull then saturate it with unthickened epoxy; work from the center toward the edges with brush or roller. When the first coat of epoxy has started to harden brush on a second to fill the “weave” in the tape [sic]. When the epoxy has cured cut off the cloth hanging below the sheer.

Page 15, step 5.

How much epoxy? What kind of roller? Are there tricky bits at the bow and stern? Builders on the forum have more to say, as do many videos on YouTube. So does John Harris’s demo video and a page at CLC’s website, so I am not left entirely without direction. It will probably all make sense a few minutes after getting started, but I find this step intimidating.

Here’s a summary of some of the answers: start with a pint of epoxy; pour it near the keel, consider heating the resin in a warm-water bath to make it even less viscous than the low-viscosity resin already is, especially in cool (basement) conditions. A 3/16-inch nap is not a bad start for a roller; cut the roller to 4 inches, Use a 1/8-inch foam roller and be prepared to tip out bubbles with a brush. You’ll need a good bit more than the specified pint for the hull — that’s a good start — but keep the batches small so they don’t kick off while you’re working. Don’t be too generous with the first coat or the cloth may float off the wood and fail to bond securely. Think “wet edge” as if you were painting, and go for it. The second coat, but not the first, may be stretched with micro-balloons to help fill the weave. Apply the second coat before the first is entirely cured, within, say 6-8 hours — any time after the first coat is tacky and within 30 hours, says the apocrypha in the book o’ the boat. The same sources say that MAS epoxies as supplied should cover 500 sq ft per gallon (to a thickness of 3 mil). The boat is ~30 inches by 20 feet, which is about 50 sq ft. There’s half a gallon of resin and a quart of hardener remaining (so I should be able to cover all remaining surfaces at least five times over to that depth. How does the woven cloth effect coverage? I’m about tin find out.

Slow down a minute.

A great deal of advice says to use 1/8-inch foam rollers, not 3/16-inch and not fiber. So why not take it? While shopping for the recommended rollers (which will be good for other tasks, too, like varnish, like coating the undersides of the decks with epoxy), I found small, knurled aluminum rollers made specifically to work with fiberglass and epoxy. (Why aren’t these mentioned? Are they newish? Anyway, worth a try.) For a total of $14 and one extra day, I can have the specific tools with which to finish this project. So step back, take another day or two.