Hawbuck Update #2


Hawbuck Update #2
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Hey Chuck,

I finally got Matt sobered up long enough to finish his sanding. Because Matt's boat is a powered canoe we added a 3/4" by 1/2" ash keel, scarfed to the outer stem. Even though I angled the sides to minimize sharp edges (fiberglass does not like sharp edges) we still made up a batch of filler out of the wood flour (collected from sanding) and used it to fill the inner edges along the keel. It worked a lot like the microballon and talc mixture I normally use for seams - also sanded pretty good. After close inspection and sanding a few pencil marks here and there we fitted a layer of 6oz glass and covered it with epoxy.

By the way - because of bad experiences with old boats - I did not cover the transom with fiberglass - due to the engine stress and vibration it seems to be the most likely place for water to get under the glass to cause future problems. Instead we just "painted" the transom with resin - any "issues" in this area will show right away and be more easily corrected.

Before the Hawbuck I have only used polyester and wasn't sure what to expect. So, I used slow-non-blushing hardener (requires 60 degrees and up temp) which is mixed 2:1 ratio (much different than 7cc/pint I use for poly). The epoxy resin soaked into the fiberglass just about the same speed as it does with polyester. The main difference is with the slow curing speed I was able to mix larger batches and not end up with interesting but useless "paperweights" like I usually do with polyester.

We mixed 10 pumps of hardener to 20 pumps of resin (with pumps supplied with the resin) and after thoroughly mixing poured it a little at a time right onto the hull. Starting at the keel and working down to the shear we used cheap (disposable) 2" paint brushes to spread the resin - a slow steady speed gave the resin time to soak into the glass. Always moving wet to dry helped avoid introducing wrinkles or air bubbles under the glass. I (being vastly more skilled) also used a 4" plastic automotive squeegee to remove excess resin or move it to a dry area. We changed brushes as the resin thickened on them and I frequently wiped the squeegee clean to keep it working properly. As we progressed I continually went back to "completed" areas to check for air bubbles (especially along the keel) and ensure everything was the way we expected.

We decided ahead of time to let the first layer cure at least four days. This will ensure the resin is fully cured - making sanding far easier than trying to work with green resin. Here's a photo - no wrinkles, no bubbles. I like the cypress, it was pleasant to work with and soaked in resin it has a nice "wood" color. Note the darker "sinker" cypress really stands out as accents. Hmm, I might just make one of these babies for my own stable. Only next time I'll hand select the wood rather than using stuff from the scrap pile - heh, heh, Matt can't read this - he's too cheap to subscribe!

Larry Pullon