Finishing and Varnish

Scrape! Yep, that’s the operative word—don’t sand, scrape! Sanding out the imperfections in the fill coats is theoretically possible, I guess, but not very practical. It would take forever. Take a look at the amount of resin scraped off in the photo below and then realize that all those darker, shiny spots are depressions that are still there after a substantial amount  of resin has been removed.

You Can Scrape a Lot of Resin and Not Touch the Glass

This is OK if You Use Light Pressure and Go Slow
Scraping can be bad—catch an edge and you can cut a pretty good divot all the way down to the glass, especially at the convex edge of a seam. Just be careful when you’re near a seam, take it slow there, and you’ll have very few problems. Scraping is magic, but it’s still a lot of work. Four hours for the bottom and two more for the top, then that much time again for sanding. That’s at least 12 hours, which you really can’t do in a day and half, more like two or two and a half days.
You can use two hands and move pretty quickly with the scraper in the middle of the flat panels, but scraping on or near the seams requires more control and less speed. When you’re near a seam, keep most of the blade flat on the panel and overhange the blade slightly. You can’t keep it flat if you ovehang a lot.

Hang the End of the Blade Over the Seam Very Slightly

You Will Catch an Edge and Cut a Divot or Deep Scimitar Groove

You’ll want to sand. Why? Because it’s hard to convince yourself that you’re not getting to deep along the seams. The flat areas go slowly, but if you bear down on a seam you will cut into it, so you don’t.

As you scrape, you’ll see small drips lines, wavy lines, and random small depressions in the fill coat. If you do get a little bit deep, you’ll suddenly see a matrix of dots. You are not in the glass. If you took one more light scrape, the dots would vanish. What you’ve found is that the glass tends to rise up (bow up) very slightly as it is bent across a convex seam. This may only be a couple thousandths, but you will see the dots more quickly along a seam than you ever will out in the middle of a flat panel. That’s not to say that there won’t be an occasional ripple in the cloth in the middle of a flat area—there will be—but if you wet out your cloth carefully, ripples will be rare.

The point is, in the left photo below you will think “oh, crap” I’ve cut into the cloth. You haven’t. This pattern will completely disappear when the varnish is applied. It’s hard to tell when you’ve definitely hit the cloth—which means you’ll have a permanent visible pattern under the varnish. The photo on the right has some specs of bright white, which the varnish cannot (and did not) turn translucent.

Sand These Lightly and Varnish Will Make Them Disappear

Hard to See, but These White Dots Are Not Going to Go Away

Name your boat. Get a laser-cut nameplate and fill the lettes with epoxy. Let it cure and sand it flat, then coat the whole thing with epoxy. I used the same color in the letters and numbers as I used for the coamings (See the Tern Construction pages for the epoxy compatible tranparent pigment). IF you mask off the area around the name plate, you can gob it on with wood putty and tape it down, then pull of the tape once the glue has cured, for a clean installation. This boat is aptly named for a double , “Two Can,” phonetically.

Two Can Paddle This Double Kayak

My varnish plan is to do the deck and coamings first, then the hull. This is definitely backwards. What you see here is the first coat, lightly sprayed on with a Finex Mini-HVLP gun. This is on the recommendation of Royce, an Airstream Forums member and outstanding woodoworker. The Finex HVLP might have been a better choice, but I wanted to be able to spray under the coaming lip without runs. I’ll use the bigger gun on the hull.

There Are a Couple Areas Where You Don't Want Varnish

I’ve masked off the cockpit and the hatch lips. I use a small foam brush to saturate the edges of the hatches to make sure the end grain is sealed and also do the vertical edge of the hatch opening. I have masked off the hatch lips because I want the contact cement to bond directly to the epoxy—the solvent in the contact cement would melt the varnish and possibly make for poor adhesion of the foam seal. In the photo below you can see I have taped a paper skirt all the way around the sheer so I won’t have to re-sand the hull before I start to varnish it.

The Hull is Protected While I Spray the Deck

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