: Hmmmm. Sorry, I really don't see this. On the other hand, this sounds like a
: great challange: guillemot on an external :-)

I don't see an external strongback to be a problem with my designs. Just screw some constant height risers to each form, aligning them to a standard reference line. People who want to build using Rob Macks' hot-melt glue method may want to do this. Likewise, it should be easy enough to cut a hole through forms intended for an external strongback.

I like my internal strongback system, but I can see myself being just as happy with an external once I got used to it. Both systems offer advantages, each has disadvantages. The finished boats work just as well no matter how you build it.

If you see an benefit of the other system which you would really like to take advantage of, you should probably use it. But if you are unsure, just go with the system the designer recommends. The other instructions will assume you use that system. Neither system has advantages which are large enough to justify switching without good reason.