: Hello Everybody,
: I'm in the process of building a 18 feet White Guide Canoe, and I am
: wondering how much material I will need. Cedar is VERY expensive here in
: Norway, so I'd like to buy just the right amount.
: A local supplier can provide me with boards 300mm x 20mm.
: Can anyone guide me in this matter ?

: I also thinking about using a combination of pine and cedar to keep my
: budget...
: Is pine okay for a canoe project ?

The White Guide boat is a wide boat with very good stability. It has had a good reputation for over a hundred years.

Whose plans are you building from? The supplier of your plans should have provided you with a list of the materials you will need.

For an 18 foot version you will need at least 5 strips which are 20 feet long, (that would be about 6.1 m long) and the work will go faster if you have at least 30 strips of this length. If the distance around the outside of the widest building form is 52 inches, then that distance would be 1.32 m. Working with boards which are 20mm thick you'll get strips which are 20mm wide, and you'll need 66 of these to go around the boat at that point. Plan on buying enough wood to make 60 to 66 strips which average 6m long. You will have some excess, but this is necessary as you need the strips to extend beyond the actual length of the boat so you have something to hold on to as you fasten them in place.

You will also need wood for the gunwales. Pine would be excellent for this area. You can make the gunwales from pine, and also make the strips of the hull, under where the gunwale will be fitted, out of pine.

Pine would also be excellent for the keel line and those 5 or 6 strips to either side of the keel which form the center of the bottom of the boat. the reason for this is that the denser pine may be more resistant to compression damage from hitting submerged rocks, or landing on rough beaches.

An 18 foot guide boat is a big boat. for a boat of this size I would NOT go under 6 mm thick strip. Gil Gilpatrick has plans for a 20 foot guide boat in his book, and he reccommends using 5/16 inch cedar strips for that. That would be about 8 mm strips. If you are ripping your boards (pine or cedar) anywhere between 6 mm and 6.3 mm you should be just fine.

I would not recommend making bead and cove edges on your strips. They are not necessary for large boats such as this as most of the curves have larger radii than on smaller boats. Square edged strips can be quickly and easily fitted over most of the boat.

You may need to make minor adjustments to the angle of the edges with a hand plane to get a tighter fit in the curved areas at the bottom of the bow and stern, but these are relatively few, and the work is done quickly.

If you want 60 strips which are about 6m long you will need at least 5 boards which are 6m long and 100 mm wide, or the equivalent. That could be 5 boards boards which are 300 mm wide and 2m long, or 15 which are 2 m long and 100 mm wide. You can mix this between cedar and pine.

While you may be able to get wide boards (300mm is our nominal 12 inch wide board) these may be more expensive than narrower boards. A long and wide board is very difficult to find, particularly if you are looking for, or asking for, clear wood. However, boards which are of a length commonly used for construction -- in the US this would be 8 foot lengths; I'm not sure what the European equivalent would be, but it is probably close -- should be easier to obtain.

Using a long, tapered joint (called a "scarph" or "scarf" joint) to connect shorter pieces of strips or boards is a common technique. Typical tapers would be somewhere between 6 to 12 times as long as the wood is wide. With a very strong glue, such as epoxy, a shorter (6:1) taper will work fine, while using a common white glue would usually require a taper of 10:1 or 12:1.

Scarf joints are only required on those boards or strips you wish to reach the full length of the boat, and to bend evenly over their length. You'll want at least 5 of these to start your stripping. After that you can simply butt a new strip against the end of one which only covers a portion of the length of the boat. These "butt" joints are not very strong by themselves, but like bricks, by staggering the plaement of these joints they are sandwiched between strips above and below them which support them. Also, the fiberglass and epoxy covering will add strength to the area around these butt joints.

So, it beomes very practical to buy shorter lengths of wood for most of your strips. One person I have read of likes to work with strips which are 5 feet (roughly 1.6m) long. This is a bit shorter than I personally like, however.

If you have lots of long strips the work goes faster.

There are two ways to make long strips. Rather than rip my strips from short boards and then join the strips together with scarf joints to make longer strips I like to scarf together short boards to make long boards. Then I rip my long strips from these long boards.

Here are the advantages and disadvantages of each method:

When you rip boards 8 to 10 feet long (in this case these boards are what I would call "shorter") you can usualy support most of the length of the board on the saw table and you need only a little additional support. If you do not have a suitable extension for the top of the saw, or a separate outfeed table, you can frequently make do with having an assistant support the end of the board as it is ripped.

When you rip boards which are 12 to 24 feet long -- or longer -- then you definitely need a large area to work, and support for both the infeed and the outfeed areas. If you can arrange a good working arrangement which supports the board and the strip as it comes off the board, then you can do the job with either short or long boards without an assistant.

When you you make a 8:1 tapered end on a 6mm (or 1/4 inch) thick strip in order to create a scarf joint you will remove wood along an area 48mm long (about 2 inches) That hardly shortens your wood. Combining two 8-foot pieces would give you a piece just two inches shorter than 16 feet. Adding another 8-foot piece to that would give you a piece 23 feet and 8 inches long with two scarf joints in it.

When you work with a 4 inch wide board (100 mm) and cut a 8:1 taper on the end for a scarf joint you give up 32 inches or 800 mm. That is a lot of waste. I usually use a 6:1 scarf on these boards, though, making my taper cover a 2 foot length of the board. (that would be 600 mm with a 100 mm board) When I join two 8-foot boards I get a longer board which is 14 feet long. Adding a third 8-foot board to that gives me a 20 foot board from which I can cut 20 foot strips.

When you scarf together the strips you need two clamps for each joint, or 1 clamp with a wide jaw, or one clamp and two wide scraps of wood which can bridge the scarf joint so that clamping pressuse is distributed evenly. After the glue in the joint has set you will need to sand the joint to get it even and remove any glue which has squeezed out. If you are going to scarf 10 strips on one day you need 10 to 20 clamps.

You need two or three clamps to secure the parts when you scarf together 4 inch boards. After the glue sets up you only need to clean up any squeezed out glu on the faces of the board (easy to do with a scraper) and then smooth or sand one edge. When you go to rip your strips this edge is the one which runs along the fence. The process of ripping the strips gives you a finished edge at all the scarf joints on all the strips with no additional effort.

Epoxy does not require a very strong clamping action, so it is practial to make your own "clamps" from blocks of scrap wood nailed to a third piece. sapce the blocks a bit further apart than the width of the board you are clamping and use wedges to tighten things. You can use the wedges created when you made the taper cuts.

When you scarf together strips you need to make 20 taper cuts to get 10 longer strips. When you scarf together the boards you make at most 2 taper cuts. If you stack the boards you can make a single diagonal cut that goes through both boards, giving a nearly perfect match. I do this with a handheld circualr saw following a line I draw on the top board. If I deviate from the line that cut is nearly the same on the top board as it is on the bottom one, so the scarf matches almost perfectly.

In either situation you can get a nearly invisible joint if you try to math the color and grain pattern fo each piece of wood at these joints. This is very easy to do. If you chose to rip shorter strips and then later scarf them into longer strips then keep them aligned after you have cut them. If you think you want to joint three strips, then group the three strips that are cut next to each other. If you want to joint two strips, then group them in pairs. with two strips you cut the tapers on the top of each strip in the pair. When one is flipped around to mate with the other the color and grain should be nearly perfect. With three strips you cut tapers on both ends of the middle strip. this matches with a taper cut on the top end of the first strip and the bottom end of the third strip.

Your 300mm wide board could be cut into 3 pieces whcih are each a little less than 100mm wide. These could be joined with the tapered scarf joints to give you a longer board from which to rip your strips, or the pieces for your gunwales.

If you encounter large knots in your boards, you can make two long parallel cuts diagonally across the board, remove the piece with the knot, and then glue the board back together again. The long diagonal cut should be at the same angle as a scarf cut (about 6:1 or 8:1) and after the glue has hardened you will have a nice "clear" board which is only a few inches shorter than what you started with.

Once you set up your saw to rip the strips, cut the cedar first. Then cut the pine. The cedar is so soft that your blade will be nearly as sharp as new when you finish. Ripping the pine will put more wear on the sawblade. As you rip the pine remember to leave some thicker pieces for use as gunwales. You can later rip these to the exact dimensions.

Good luck with finding your wood.

Hope this helps

PGJ