Interesting to see a couple of threads about design happen simultaneously . 1 , the post by LSD about his new board and 2 , discussion about the high volume of the Mctavish boards. DJ said in his post about the LSD board that there was not a sharp rail in sight. I thought generally rails became sharper towards the rear. I took this as a given when I shaped my boards . What I was trying to do was to make the narrowest rail I could and the sharpest rail towards the tail ,so I ended up making a step rail. Are step rails no good? LSD's rails seem to be very full and towards the tail they don't seem to foil down much at all. OK, so what does this mean? , should I be bothered trying to reduce the rail thickness or should I make the rails like Deans board. OK, item 2 , the volume of the Mctavish boards. Are people saying that too thick a board is bad for performance? , but hang on I've seem vids of LSDs boards and they seem to go well , those new C4 boards have thick chunky rails and they seem to be a really good performance board . I'm just trying to get some design do's and don'ts here . The shed is empty and I've got enough glass and epoxy to do a new lightweight , I just need more design advice.