Building a Scale-Model Prospector Canoe

I decided to build a scale model canoe as a present for my new niece (recently born) to be used as a piece of furniture. I picked the Prospector design from Canoecraft, because the Prospector is a freely-available design and is nearly 36" wide, which would result in a reasonably wide scale model.

The Forms

I took the offsets for the Peterborough Canadien canoe from Canoecraft, by Ted Moores and Merilyn Mohr. As I wasn't going to use a stem, I had to change the bow and stern offsets. I then reduced the dimensions of the forms to 2/3 scale for height and width, and 1/2 scale for length.

I produced full-size (scale) plots for each even-numbered form and the end forms. I had to make a few minor changes to the offsets so that I could produce smooth plots. These plots were glued onto 5/8" particle board using contact cement. I had the 4' by 8' particle board sliced into several 18" strips at Home Depot so that I didn't have to make these cuts myself. I cut the forms out with a jigsaw and smoothed them with a random-orbital sander.

I mounted the forms on a small strongback that was part of the shipping boxes I had received from Classic Boat Kits. This strongback came in two 8'6" pieces, but, of course, I only had to use one of the pieces. I again used carriage bolts with oversize holes, as suggested by Green Valley Boat Works, to attach the forms to the mounting blocks, as this allows for the forms to be adjusted if necessary.

I aligned the forms by eye. As the scale model is only eight feet long, I found that I could easily see any forms that were out of alignment and adjust them accordingly. I also trimmed the end forms to allow the strips to lie correctly on them, again with the random-orbital sander.

The entire process of making, mounting, adjusting, and fairing the forms took only about 4 hours total, spread out over late October 2000 and early November 2000. (Part of the reason for spreading out this part of the process so long was that I was waiting for the strips, and part of the reason was that the digital camera needed to be fixed.)

Stripping

When I knew that the strips were on their way, and the camera had been fixed, I started the stripping process. I used some left-over Western Red Cedar and Northern White Cedar strips to create a pattern on the upper sides of the canoe. The lower sides and bottom of the canoe were stripped exclusively in White Cedar.

The first strip was laid parallel to the sheer line for the middle of the canoe, but not bent down completely to the sheer line at the ends. This turned out to be a very good idea, as otherwise some strips would have had a severe bend just at the end of the canoe.

The first few strips went quite fast. Each strip took about 10 minutes (per side). Between strips I had to wait for the glue to set up, so I couldn't do a lot of strips at once. Further up the sides of the canoe the strips had to bend more and took slightly longer, up to 15 minutes per strip, but the stripping still went quite fast.

As I reached the turn of the bilges the strips had to bend a lot. Here it was very noticeable that I was using 3/4" strips on a small canoe. Some of the strips were very hard to keep under control and they all took longer to do, up to about 20 minutes per strip. (If I have to build another model, I might switch to 1/2" strips.) I used a bar clamp with weights on the end to twist the strips; this made placing the strips considerably easier. However, before I could remove the clamps and the tape, the glue had to be completely set, which took at least two hours. This slowed down progress considerably.

Once I cleared the turn of the bilges the bottom went faster. I used a double herringbone pattern on the bottom, as I like the look of this pattern best. The only problem with this pattern is that it requires that the end of the strips be placed in pockets formed by the previous two strips. The first several strips on the bottom went fine, but for the last few strips, the small size of the model was evident, as the strips had to bend in a short length. I tried several ways of getting the strips to bend, including steaming (which worked reasonably well). What worked best was cutting open the pockets so that I could put the end of the next strip in with less bending. I then glued the cut-out section back in. (The pictures of the bottom and ends are from after fiberglass was put on, as I did not have access to a camera when I was stripping the bottom and upper ends.)

I cut out the top of the cove of the second- and third-last strips so that the last strip could just be placed in, without having to get it under the coves. This worked reasonably well, but I stil had to carefully cut and sand the last strip to the correct shape.

The upper ends were stripped in a pattern that continued the pattern on the upper sides, with alternation between Red and White Cedar. They were done at the same time as the bottom of the model.

The stripping process started on November 8, 2000, and finished, after a number of breaks due to trips and visitors, on November 26, 2000.

Glassing

I had enough System Three Clear Coat epoxy for the canoe, but I needed fiberglass. I decided to try a very different kind of fiberglass from the loose-weave 6 oz. fiberglass I had used for my two previous canoes. I purchased a large amount of tight-weave (60x64 thread count) 2.55 oz. fiberglass from CST at a very reasonable price. I planned on using a single layer of this fiberglass in this project, but then use two layers of it on my next project (probably a Georgian Bay kayak). I'll see how well this fiberglass works out.

Glassing the Outside

I smoothed the outside of the model with my random-orbital sander. I started with 40-grit paper for the rough sanding. Then I switched to 60-grit paper for smoothing and then 100-grit for final smoothing. The sanding went fast, taking only about 2 hours on 26 November.

I put a seal coat of System 3 Clear Coat epoxy on the outside of the model and filled in the gaps with a mixture of epoxy, wood flour, and quartz microspheres. When the seal coat cured enough to sand (24 hours later) I very lightly sanded the canoe to remove any rough spots. I then put the fiberglass on, cut it to shape with a bit wrapped around the ends, and applied a glue coat. The tight-weave fiberglass was a bit harder to wet out than loose-weave fiberglass and somewhat harder to fit around corners, but there were no real problems. (The only problem was self-inflicted - I mixed up a too-large amount of epoxy and it was a bit sticky by the end.)

I used two fill coats of System 3 Clear Coat epoxy. This was more than sufficient, except that I had a few places where the fiberglass lifted a bit, and needed to fill in these places. I sanded a bit before each fill coat, just to knock down the few imperfections. After the last coat, I sanded the outside in preparation for varnishing.

Epoxying and glassing the outside took about 5 hours (1 hour for the seal coat, 1 hour for fitting the fiberglass, 1.5 hours for the glue coat, about 1/2 hour for each of the fill coats, and about 1/2 hour for sanding), from 26 November to 3 December. I didn't have acces to a camera for this process, so I don't have any pictures.

Glassing the Inside

I took the canoe off the forms an put it on my canoe stands to smooth the inside. Smoothing the inside, as usual, was much more annoying than smoothing the outside. I used the sander, with several hand sanding tools to do the ends of the canoe. Smoothing the inside took about 4 hours, on 3 and 4 December.

I put a seal coat on the inside. I also put an extra coat on the ends of the outside, to fill in the transition where the wrapped-around fiberglass ended. As the temperatures in the garage were quite cold, I used a space heater to warm the canoe up to a reasonable temperature to allow the epoxy to cure. Turning the canoe upside down on the canoe stand allowed me to put the space heater under the canoe, which trapped the warm air inside the canoe, and made quite a difference in the tempurature.

When the seal coat had become non-tacky I laid out the fiberglass. First I loosely fitted the fiberglass inside the canoe. Then I smoothed out the fiberglass, starting at the middle and working towards each end. I used spring clamps to hold the fiberglass up during the smoothing process, placing new clamps as I went along. Finally I fit the fiberglass into the ends of the canoe, and trimmed it off to fit flush. This last placing and trimming was difficult because the ends of the canoe were so sharp.

I glued the fiberglass in, again starting at the middle and working to the ends. I found working in this small canoe to be frustrating as there was less space to work in than in a full-size canoe, and the ends were quite sharp. I ended up with a bit of a mess at the ends and had to leave some fiberglass threads sticking up, to be trimmed later.

I used the space heater to warm up the canoe after the glue coat, but after a night without the heater. Unfortunately, this didn't work well, as the glue was so cold overnight that it didn't cure at all and the heater warmed the glue back up to the runny stage. The fiberglass separated from the wood in about 10 places, and I had to cut these places open and press the air out. Fortunately the glue was still sticky, so I didn't have to cut the fiberglass out completely. I then put on one filler coat.

Epoxying and glassing the inside took about 5 hours (1 hour for the seal coat, 1 hour for fitting the fiberglass, 2 hours for the glue coat, 1/2 hour for fixing the bubbles, and about 1/2 hour for the fill coat), from 4 December to 8 December.

The Trim

I attached the outwales to the canoe in the usual fashion, making epoxy glue with plastic mini-fibers and adding wood flour for colour. I clamped the outwales to the canoe with spring clamps. The outwales were easy to bend and attach. Unfortunately, due to the cold temperatures, the glue took a couple of days to set.

I made short decks out of some left-over maple, epoxy-glued them in place, securing them with bar clamps. I then cut the inwales to length and drilled and installed #10x32 Heli-Coil inserts for the thwart. I set the thwart up slightly off-center so that the canoe could be paddled solo. (Even though this is a scale model, it should be sea-worthy.) I epoxy-glued the inwales in place and clamped them with spring clamps.

I made up a thwart, again from left-over maple and drilled holes in it. I used threaded brass rods and nuts to attach the thwart to the inwales, drilling small recesses to hide the nuts. (I don't know if the thwart is really necessary, but I decided to make one, just in case.) When the glue for the inwales had set and dried, I sanded the gunwales and decks and put a coat of epoxy on them and on the thwart.

Doing the trim took about 5 hours, from 9 December to 16 December.

Varnishing

I put two coats of varnish on the canoe. Varnishing took a couple of hours from 18 December to 23 December. I then gave it to my 6-month-old neice as her Christmas present. The canoe looks great in my brothers living room, filled with toys and other baby stuff, although I don't (yet) have a picture of it.