A quick strongback

I'm about to start building the first boats in my new shop. I'm going to exhibit at the Maine Boat Builder's Show and I need some boats to bring to it. I've decided to bring a Nymph canoe and while I am at it I figured I would build two. Unfortunately, I only have one strongback. So, yesterday I decided to build another. A strongback should be rigid and straight. I looked around my shop to see what materials I had on hand and saw I had a few #2 pine boards that were quite straight. I decided to turn these into a strongback.

First I needed to flatten out slight warping in some of the boards. If I owned jointer I would have faced one side, but I don't so I just ran them throught the planer. Then I had to straighten the edges, again a job for the jointer I don't have, so I ran them through the table saw to trim off both edges.

Essentially I'm just making a box beam with two sides and a top and bottom. To keep this beam from twisting I added spacers distributed along the length. These spacer maintain the distance between the parts and keep the beam from twisting. My pine boards were 8' long and I wanted a 9.5' strongback so I had to butt-together pieces to create the length. I inserted spacers behind each joint to provide a little more reinforcement. I applied glue to the long seams and tacked everything together with finish nails. When the glue dries I'll just clamp the beam on top of some saw horses and start setting up the forms.


Box Beam Strongback
Here is the strongback before putting on the top. All joints are glued and held in place with finish nails. The ends will be trimmed to length when it is done.