Wednesday, August 27, 2008

Building a Cedar and Canvas Canoe : Thursday

The first thing that happend on Thursday morning was that we removed the canoe from the forms. This is done before the ends are closed up so that you can actually remove the canoe from the forms. I was a bit apprehensive about this step, but it was really pretty easy. The wires on the stems are released, you push gently down on the hull and voila, the inwales spread away from the mold under the tension from the ribs.

Temporary braces are seen in place to keep the canoe from spreading fully open.

The stems are then dovetailed by hand to receive the inwales:

The deck is then notched to fit over the top of the stem:

The deck's location is marked on the inwale and the stem is pulled up to an appropriate location. This is done by feel - you don't want to put too much strain on the stem by pulling it up too hard. At this point, the deck is mounted with some bronze screws to one of the inwales:

At this point, a highly technical piece of hardware is used. It's called the "standy-uppy" :

The "standy-uppy" is screwed to the floor and is simply there to help hold the canoe in position while the level is placed on the thwart. This is critical to getting a canoe that is straight. Once this is in place, the deck and stem are slid back and forth until the stems are plumb. Once this adjustment is made, the deck is screwed to the other inwale to keep it in place:

Once the deck is installed, it was time to shape and steam the cant ribs. Cant ribs are not like any of the other ribs in that they don't bend over the top of the boat. They are shaped to slide into position alongside the stem in the bow and stern of the canoe. These are cut from standard ribs that are left over from the steaming process. They are shaped by hand when hot and then clenched in place:

The top of the cant rib is then notched to fit up agains the deck. Sometimes these are thinned as well.

After the top of the cant rib is shaped, they are nailed to the inwale using bronze ring shank nails. The end of the stems and the deck have a screw installed to keep them together as well.

Now that all of the ribs and decks are in place, it is time to install the temporary thwarts by screwing them in place. The temporary thwarts were simply rough copies of the finished parts in terms of lenght and angle. Once these were in place, the last of the planking was installed. (WHISKEY PLANK!)

Once the last of this planking is installed, it is time to mark it and trim it. Here is the marking gage in action. It makes a line just above the bottom of the inwale so that when the canvas is cut flush, the outwale will cover the edge of the canvas and wood.

The planking is then cut down to the line using a utility knife to score and then cut. This planking is only 5/32" thick, so it isn't much work.

Once the planking is cut down, it is time to make certain that all of the tacks have been properly clenched and that there are no missing tacks. While in most areas, the steel bands did a good job of clenching the tacks, in some areas they aren't clenched at all. You simply get in the boat using a clenching iron (seen in top photo in this post) and back up the tacks on the inside of the rib. Then you give a good sharp rap with a hammer on the tacks on the outside. It is at this point that you realize that there are literally thousands of brass tacks used to build one of these canoes.


After all of the tacks have been set, the last step for the day is to take a swab and some boiling water and wipe down the whole hull to get rid of any "hammer blossoms"

After we completed this task, we retreived our mahogany outwales that had been soaking in the pond and steam bent them over the forms seen in Friday's post. After that we called it a day.

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