Learner, I built one of these many years ago. Not too complicated. Cut the V in both blocks at the same time on a bandsaw. Do this by either screwing together or using double sided tape. While the blocks are still joined, drill a whole the size of a dowel of your choice completely through one and halfway into the bottom one. Glue dowels into the half drilled holes. They should fit somewhat loosely through the other block. You now have an adjustable length device which could make things a little more user friendly. Good luck. kev