Preparing and Fiberglassing the Interior

The process of fiberglassing the interior of the hull is very similar to what was done on the exterior but a few of the steps are very different. Planing and sanding the exterior planks is much easier and when the hull is completed, the exterior is generally fairer than the interior. When planking the hull, I always try to justify the planks so that the interior will need a minimum amount of work even if it results in the exterior being a little rough (which can be easily remedied).

Hours (and hours) are spent scraping and sanding the interior to get everything just right. Fairing the interior is much more difficult than fairing the exterior.

Before fiberglassing, a fillet must be formed around the lower part of each stem. This fillet has two purposes. It will add strength to the part of the hull that takes the most abuse and also gives the fiberglass a surface it can conform to.

This photo shows the make-up of the stem. Outer stem, inner stem, fillet on each side for the interior fiberglass strip to lie on.

The fiberglass is carefully laid out and fitted to the curvaceous interior. Much care is taken to do this without snagging the fiberglass on trimmed exterior fiberglass along the gunwales.

We avoid distorting the fibers by using a four-inch wide, soft bristled paintbrush to conform the fiberglass to the hull and to smooth out the wrinkles. Some snags and imperfections are inevitable but can be worked out using a small pick and a stiff bristled brush (i.e. toothbrush). Sunlight on the finished boat will show these flaws if not taken care of now.

The fiberglass is difficult to work into the stems, so we do this in several stages. First, a three-inch strip is wetted out down the center of the stem. Then, fiberglass pieces about 18 inches long are wetted out on each side of the stem (overlapping the three inch strip). Then the main piece of fiberglass is fitted and trimmed so that it overlaps the 18 inch pieces. This method is much, much easier than trying to do it all in one piece.

Finally, the main section is wetted out. Two or three more coats of epoxy will follow this.

Prepping the Hull for Fiberglassing

After planing the outer stems into shape, many hours are spent preparing the hull for fiberglassing. At the beginning of this stage, the hull is a series of edge glued rectangular planks and is fairly rough. The goal is to transform the hull, with all of its hard edges, into a smoothly curved, free flowing shape.

Fairing the hull is accomplished by first methodically planing the seams of the planks. For me, planing is one of the most enjoyable steps of the building process. I like it because you can see immediate results and I know that it is saving me a few hours of sanding.

After the hull has been planed, the sanding begins. It takes many hours of sanding to get things just right. Sanding is hard work and after several hours, becomes somewhat tedious. If planing is one of the most enjoyable steps, then sanding is one of the least. It is, however, the most critical step in determining the final shape of the canoe and much care must be taken to get everything just right.

After all of the highs, lows, and wobbles have been sanded out of the hull, the final step is to "raise the grain". Raising the grain is accomplished be wetting the hull down with water which swells the wood fibers. After the hull has dried, the raised fibers are given a final sanding with fine sand paper. This step will keep the grain from rising when the fiberglass and epoxy are applied. The wet hull gives us a preview of what the wood is going to eventually look like.

Refinishing the Interior

When we took on this project, I had envisioned doing a light but thorough sanding of the interior followed by two or three coats of varnish. After sanding a little, I realized that the original varnish was no longer in tact in the area around each of the approximately 1,000+ plank/rib clench nails. To assure lasting protection and integrity, it was decided that all of the old varnish would need to be removed.

Stripping the old varnish turned out to be a more daunting task than I had originally envisioned. The chemical stripper that I used had a hard time breaking down the varnish. It took several coats of stripper and much scraping and rubbing to get down to the bare wood. With some experimenting, it was found that the most productive way to remove the varnish was with a heat gun and a scraper.

Most of the varnish was removed with the heat gun and scraper. Then the chemical stripper was used to remove the final bits from seams and tight spaces. The stripped area was then sanded and bleached. The bleach was used in hopes of lightening the dark stains in the wood around each clench nail. I don't believe the bleach had any effect on the stains. This was fine because the stains actually contribute to that natural patina we love so well.

After the interior was stripped and sanded, a few minor repairs had to be made before we could begin with the varnishing. Two of the floor boards had suffered from rot. Wood from the damaged areas was removed and the new cedar was spliced in. The punctured plank was repaired by removing the damaged area and a new piece was shaped and epoxied in its place using West Systems epoxy.

The keel bolts (screws) were very corroded and the wood around them had deteriorated over time. I removed the affected wood, filled the void with putty made of West Systems epoxy and wood flour. Mahogany plates were placed over each repaired keel bolt for cosmetic and structural reasons.

The first of three coats of Epifanes Gloss Clear Varnish brought out the rich colors of the cedar planking and ribs. The next couple of coats brought out the bright luster. The gunnels had been sanded earlier and were now varnished as well. The outwales would be removed for the canvassing and needed more varnish work later after the final assembly.