Releveling the Frames

Over the past week, I've managed to put the building frame back into alignment. Here you can see the boat set up in the new garage. What you can't really see in the photo is that the floor in the new garage is not level. There are two floor drains (required by the building code) and the floor slopes toward them. The building frame was originally constructed on a flat floor, and so now has a slight sag in the middle.

When I originally set up the frame, I used a series of holes centered on cross hairs to align the the station moulds. Running a string through these showed that some frames were over 1/4 inch out of alignment. This meant that I needed to go back an realign everything. When I first did this, I used a combination of pipe clamps and a hammer to align everything, and a spirit level, string line, and a piece of plywood cut to exactly 24" width to align everything. The two pipe clamps were reversed to work in "spreader" mode and adjusted the mould vertically on the left and right hand sides. This allowed me to get the correct height and make the frame level. Left and right adjustment was done with the hammer.

I set up the pipe clamps as before, but this time there was no opportunity to use the hammer. Raising one side of the mould would force it into the sloped hull on that side, pushing the mould toward the other side of the boat. With delicate adjustment of the pipe clamps, I was able to get each frame centered both vertically and horizontally.

In a perfect world, the moulds would now be level as well. Sadly this was not the case. The problem, as I see it, is that the floor under the building frame is not only low in the center, but also sloped from left to right.

So... I used my laser level, piles of boxes and scrap wood, a crowbar and shims to make sure each frame is level. By carefully placing the laser level, I could place a laser dot on the two lower corners of a mould, which determine the position of the sheer at that station. Then I used a crowbar to lift the low side and insert a shim (or two (or three)) to make the mould level. I started by making the stem and stern posts vertical, using a small spirit level. Then I worked from the ends toward the middle. Each time I leveled a frame, I checked the others again to make sure they had not been thrown out by the adjustment. After I was done, I had all the frames within 1/16" of level.
Then, with fear in my heart, I climbed back under the boat to see if the frames were still aligned. Miraculously, they were. At least within one or two pencil-line-widths. I pronounced that good enough, and proudly told my wife what I had done and that I was ready to start building again.
"Are you sure the moulds aren't tilted fore-and-aft?"