: A picture is worth a thousand words.

Marcel, that's good. although for it to work, you need to have a good square strong back.

I'm building my first w/strip kayak and spent a lot of time setting everything up, cutting forms, building horses made for building a kayak etc...BUT I thought it would be ok to use a 2x4 for the S/B ..(I know) it's done all the time, I have all the forms set up and have even started stripping but, my advise for anyone building there first W/S kayak is to take the extra time and build a good S/B. I will next time.
I mounted string boards on either end (for and aft) and ran strings down both sides and one down the center, all running just off the largest form. made a T shaped jig from very straight 1x2"s so that 3 ends went just a bit past the 3 strings...lined the jig on 3 reference lines and spring clamped it to the form. moved the form around till the 3 ends of the T made contact with the 3 strings and popped a nail in it with a nail gun. (I like my nail gun) I don't see how I would have done it with screws. but anyway, it worked out good and the forms were perfectly aligned. I just think it would have been much less a headache if I had a good square strong back. I'm building the expedition and finding a perfect 2x4 was imposable..my method worked and was very accurate..

I think I'll use Marcels idea next time, with a good S/B