The day following the glassing of the bottom exterior of the hull I turned the canoe over and prepared to glass the inside. First, I gave the inside a good vacuum cleaning to remove any wood dust or other detritus. Then I used the same plastic based masking tape as before to mask the edges of the number three planks. However we also need to create a fillet between the one and two planks and along the centre line of the keel to provide a smooth line for the cloth to follow. Glass cloth does not do sharp transitions. I used paper masking tape to mark the outside limits of the centre line fillet and to mark the limits of the fillets between the one and two planks. I aimed for quite narrow fillets in each case.
Next I laid the remaining roll of glass cloth in the bottom of the boat and trimmed it to the outer limits of the masking tape running along the number three planks. I then carefully removed the cloth and set it to one side.
I then mixed a batch of epoxy and added plenty of wood flour to get a nice, thick filler. I applied the filler to the prepared and masked joints using a soft plastic pallet knife purloined from the kitchen. Around the middle of the centre line of the keel the angle where the planks meet is pretty shallow but it is worth ensuring that sufficient filler is applied even here to get a contiguous fillet from end to end. This job is best done with a sequence of small batches of thickened mix as the required quantity is a little difficult to decide in advance.
Once the fillets had been created I removed the masking tape strips – with the exception of those strips protecting the number three planks. I then carefully replaced the glass cloth back in the bottom of the boat – stretching it out but being careful to not disturb the still soft fillets in the plank joints. Then it was back to the formula of mixing small batches of un-thickened epoxy and using these to wet out the cloth over the two sets of planks and the fillets. This is slightly more of a fiddle that when working the outside of the hull but the practice of the previous day keeps the process flowing. If all goes well, you will end up with a neatly glassed bottom with three attractive dark lines running fore and aft marking the joints between the planks. The glass cloth and the wetting out process nicely finishes the fillets although you should probably take care not to apply too much pressure as that might distort the lines.
In spare moments while waiting for the resin and glass cloth to cure sufficiently to allow the trimming and removal of the excess along with the masking tape I took the time to shape the back face of the seat doublers and to glue then into their intended locations on the inwales.
The decks:
A piece of advice for those who have followed this process from the beginning. Go back and do not cut out the decks from the ply sheets. Instead cut out two rectangles of plywood wider and longer than the provided deck lines. Why? Well the bulkhead fitting is a bit of a trial and error process where you strive to get them in place and to fair the lines of the unglued hull. This combined with a number of other factors means that while your canoe will hopefully have a pleasing sweep of lines they will probably vary a tad from the designer’s original drawing – and probably from his or her first build. If you take this advice then you can offer up your deck ‘blanks’ and draw around the lines of the outwale to get the exact shape and length for each deck. Cut the outer line of the deck the thickness of the outwales in from the marked line and then find a nice curve to act as a guide for the final curve above the bulkheads.
If you did cut out the decks to the designer’s lines (like I did) then you will find that you have to adjust the line – and this will a bit more difficult if you can’t use the outwale curves to assist.
I cut my splashguards from some oak stock and glued them onto the decks - once again demonstrating that I am much better at cutting convex than concave curves – but they do not look too bad and the colour contrast is nice.
Now the next piece of advice – something I wish I had thought of when gluing my decks in place, instead of a couple of days later. Shape and glue a strip of plywood to sit behind the bulkheads and to accurately meet the line of the deck when fitted. It might even make sense to shave a little off the bulkhead tops to give a clear gap between these edges and the deck line. If you are as ham fisted as me then this will save a rather bodged joint between the bulkhead and the deck after gluing. With the plywood piece in place, filling the joint would be simple and clean
I also took some time to make two simple seats from oak strips I ripped from some lengths left over from cutting the inwales and outwales. I also cut a section of mahogany to form a thwart – cutting a rough hourglass shape and then sitting in the sunshine to sand the curves until I was happy with the look and it felt good in my hands.
I varnished the seats and thwart using the “duffers” method. This differs from the manufacturer’s recommendation printed on the tin. I suspect that varnish manufacturers deliberately list a complex sequence of steps (including some specialised thinners) so they can be pretty sure that no-one ever follows them exactly – giving them an “out” when anything goes wrong. My method involves applying three coats of un-thinned varnish; allowing the minimum recommended elapsed time between coats. I then rub down any roughness caused by raised wood fibres still pushing through the varnish surface with very fine wet and dry paper and then apply a fourth coat. Job done, with a nice deep glossy finish every time.
Next I laid the remaining roll of glass cloth in the bottom of the boat and trimmed it to the outer limits of the masking tape running along the number three planks. I then carefully removed the cloth and set it to one side.
I then mixed a batch of epoxy and added plenty of wood flour to get a nice, thick filler. I applied the filler to the prepared and masked joints using a soft plastic pallet knife purloined from the kitchen. Around the middle of the centre line of the keel the angle where the planks meet is pretty shallow but it is worth ensuring that sufficient filler is applied even here to get a contiguous fillet from end to end. This job is best done with a sequence of small batches of thickened mix as the required quantity is a little difficult to decide in advance.
Once the fillets had been created I removed the masking tape strips – with the exception of those strips protecting the number three planks. I then carefully replaced the glass cloth back in the bottom of the boat – stretching it out but being careful to not disturb the still soft fillets in the plank joints. Then it was back to the formula of mixing small batches of un-thickened epoxy and using these to wet out the cloth over the two sets of planks and the fillets. This is slightly more of a fiddle that when working the outside of the hull but the practice of the previous day keeps the process flowing. If all goes well, you will end up with a neatly glassed bottom with three attractive dark lines running fore and aft marking the joints between the planks. The glass cloth and the wetting out process nicely finishes the fillets although you should probably take care not to apply too much pressure as that might distort the lines.
In spare moments while waiting for the resin and glass cloth to cure sufficiently to allow the trimming and removal of the excess along with the masking tape I took the time to shape the back face of the seat doublers and to glue then into their intended locations on the inwales.
The decks:
A piece of advice for those who have followed this process from the beginning. Go back and do not cut out the decks from the ply sheets. Instead cut out two rectangles of plywood wider and longer than the provided deck lines. Why? Well the bulkhead fitting is a bit of a trial and error process where you strive to get them in place and to fair the lines of the unglued hull. This combined with a number of other factors means that while your canoe will hopefully have a pleasing sweep of lines they will probably vary a tad from the designer’s original drawing – and probably from his or her first build. If you take this advice then you can offer up your deck ‘blanks’ and draw around the lines of the outwale to get the exact shape and length for each deck. Cut the outer line of the deck the thickness of the outwales in from the marked line and then find a nice curve to act as a guide for the final curve above the bulkheads.
If you did cut out the decks to the designer’s lines (like I did) then you will find that you have to adjust the line – and this will a bit more difficult if you can’t use the outwale curves to assist.
I cut my splashguards from some oak stock and glued them onto the decks - once again demonstrating that I am much better at cutting convex than concave curves – but they do not look too bad and the colour contrast is nice.
Now the next piece of advice – something I wish I had thought of when gluing my decks in place, instead of a couple of days later. Shape and glue a strip of plywood to sit behind the bulkheads and to accurately meet the line of the deck when fitted. It might even make sense to shave a little off the bulkhead tops to give a clear gap between these edges and the deck line. If you are as ham fisted as me then this will save a rather bodged joint between the bulkhead and the deck after gluing. With the plywood piece in place, filling the joint would be simple and clean
I also took some time to make two simple seats from oak strips I ripped from some lengths left over from cutting the inwales and outwales. I also cut a section of mahogany to form a thwart – cutting a rough hourglass shape and then sitting in the sunshine to sand the curves until I was happy with the look and it felt good in my hands.
I varnished the seats and thwart using the “duffers” method. This differs from the manufacturer’s recommendation printed on the tin. I suspect that varnish manufacturers deliberately list a complex sequence of steps (including some specialised thinners) so they can be pretty sure that no-one ever follows them exactly – giving them an “out” when anything goes wrong. My method involves applying three coats of un-thinned varnish; allowing the minimum recommended elapsed time between coats. I then rub down any roughness caused by raised wood fibres still pushing through the varnish surface with very fine wet and dry paper and then apply a fourth coat. Job done, with a nice deep glossy finish every time.
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