: OK never mind on the section height, I see now I will just pick and
: arbitrary height ( say 3" ) and then add that to the offset
: and measure to the bottom of the keel ( which I will have to
: install a stub of to measure against ) Same for the aft section.

Station height, it's important, sets the proper amount of rocker in the keel or you'll have hull not to the shape the designer intended. I use a "U" shaped piece cut from 3/4" plywood attached to a 2x2 (cut from a 2x4 to insure it's actually square) as supports on the ends. The U shaped piece I temporarily screw to the first and last frames to set the rocker then screw the 2x2 to the top of the strongback, this holds those two frames in the proper alignment. There are pictures of these I think on the Sea Bee the class built pictures on Tom's site. Then you have to find the frames with zero height offset from the station plans and insure that the keel sits flat on the top of the strongback at those stations. I normally just use a pair of drywall screws, one on each side of the keel, as a temporary clamp to hold the keel down at that location. Once all the stringers are in place and attached to the frames permanantly then all these supports can be removed.

You do need to sometimes (wood bends sometimes inconsistantly from one piece to another) twist the whole kayak frame once it's all temporarily attached to each other (I use wire ties to do the initial attachment) to get the frame level. Putting a scrap piece of wood across the gunwales and pulling down on the high side then lashing this in place holds everything straight until it's permanantly attached.

Bill H.