Glassing the interior

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.

That canoe project (Mike Griffiths)

After fitting the inwales and outwales I took the time to give the canoe hull an initial rub down. I concentrated on where I had filled the wire holes and on any marks left by the wires on the corners of the planks – being careful to preserve the lines of the “step”.  One exception was that I knocked down the sharp corner between planks numbered one and two on the inside of the hull as this joint was going to be bridged by the fibreglass cloth re-enforcing for the bottom of the hull.

Reading my building bible had made me apprehensive about the process of glassing the bottom of the hull. The suggested technique was to pour on a quantity of epoxy resin and then to brush that out – adding resin where the cloth was not properly wetted but removing resin where the cloth was floating. It all sounded rather hectic and off-putting with inevitable variations in “pot life” making things just that bit more exciting. By ignoring the book and following some good alternate advice the reality was very different. Unhurried and straightforward, with the inside of the hull only slightly more awkward than the exterior.

Glassing the hull:

Let me describe the process, starting with the exterior where only the number one planks need the application of glass cloth. First, I applied masking tape to the edge of the number two planks. I found the best tape for this purpose was a plastic based one intended (I think) for use when painting windows) although a paper based tape would be fine and was what I used elsewhere.
 I had taken my roll of glass cloth into the house and taken advantage of a wooden floored corridor to cut the roll into two strips - one a little wider than the width of the two number one planks at their widest. The other strip I was confident would be wide enough to bridge the bottom on the inside. I laid the narrower strip along the hull and trimmed it so that the edges protruded a little beyond the masking tape protecting the edges of the number two planks. Material from the ends of the strip was going to be used later to cover the plank ends where they meet at the bow and stern.
My only other preparation was to trim a cheapish paintbrush so that the hairs were only 15mm or so long – giving me a mildly stiff brush which would not pick up too much resin. If you follow on and do things as I did them, then it is worth preparing three such brushes – sizes are not important but I found those with a 5cm width to work very well. If you clean the brushes after use then they can be used again later in the build process.

I mixed a small batch of epoxy resin (four pumps) in a pot and then, starting in the middle of the canoe at the centre line, I began to wet out the glass cloth using my modified paintbrush. Work enough resin into the cloth to make it transparent but not enough for the resin to build up on top of the cloth. The idea is to wet the cloth thoroughly but to leave a slightly matt finish – certainly not glossy. Continue working towards the outside edge of the planks and towards both the bow and stern. When you run out of epoxy – just mix another batch in the same pot and keep working. You can adjust the mix quantity towards the end. By mixing small batches you can take your time, working steadily towards the finish.

All you have to do now is clean your brush (if you have the relevant solvent) and wait for the epoxy to start to go off.  This is also a good moment to cut two strips of glass cloth from the spare ends “on the bias” to cover the stem and stern. The strips should be cut at 45 degrees to the weave of the cloth as this will maximise the number of threads crossing the plank joints while also being easy to stretch around the curves. 

Depending upon the ambient temperature your wait might be just a few minutes or even a couple of hours. When things feel right, load a Stanley Knife with a fresh blade and use this to cut through the resin and glass at the edge of the number one plank – peeling the excess glass cloth away with the masking tape. The way the planks are set makes this particularly easy on the outside of the hull.

Mix another small batch of un-thickened epoxy and paint a thin layer onto the planks at the stem and stern where your bias cut strips of cloth will be located. (This was why you needed the second prepared brush.) This will help hold the cloth into place while you wet it out and stretch it to shape. Lay the cloth pieces over the epoxy and then wet them out. Then I found it simplest to manage the final shaping and smoothing using my gloved hands.
I also decided to double up the glass on the keel by adding a length of woven glass tape down the centre line of the hull. I cut the tape to length and then stuck it in place – taking advantage of the fact that the epoxy from the initial layer of glass cloth was still just tacky. I then took up my third prepared brush and wetted out the glass tape, working from the middle of the boat and using small batches of epoxy just as before.

Thus I was able to re-enforce the bottom of the canoe in a single, rather pleasant working session – although I did manage to get through five pairs of protective gloves.

The prototype single

Just a couple of pics to prove that the prototype floats.

Over Engineered

I have been working on a kayak loader as we are trying to manage with only one vehicle. I like the general idea of the Kari-Tek Easy Load but wanted to be able to adapt the loader to different car and kayak combinations. Prototypes came and went until I got to this:

Prototype kayak loader

Most of the aluminium and the sliding mechanism is from a cheap step-ladder (much cheaper than buying stock), with a few bits and pieces of scrap. On the plus side, it is relatively easy to load one fully laden plastic kayak - but when you add the second kayak, it is hard to lift and slide. On the subject of sliding, the mechanism attracts sand (of course) which you can safely say, does not help.

There are various solutions to the problem on the web - mostly ways of protecting your car as you slide the kayak onto the roofrack - with one bright idea - that of loading from the side - where the rack is much closer to the perimeter of the car. This plus an observation from Catherine along the lines of 'can't you just have supports that slide out from the roof bars?' prompted the following design:

Simple Kayak Loader

The roof bar extensions are just a push fit, and the cross bar stops the kayak rubbing against the car - simples. If you have central supports on the bars (I normally do, but not shown in this picture), you just load the second kayak from the other side. So, no moving parts, light and easy to pack away - cheap.

Time to turn the old prototype into a loft ladder.