Nice job on the board and nice job on the fins. You really nailed the rocker, which a lot of people don't do. Moon keels aren't my preference but if you're enjoying the setup then that is all that matters.
For the back side of the fins, I use between 4 and 6 layers of 6oz. I do that before I even cut the template out. That adds thickness to the panel and it leaves a halo once you foil it so that you don't have to build up the edges to protect them. It ends up being heavier than an all-wood keel but not nearly as heavy ad a solid fiberglass keel.
Yes good job on that board. You worked out the design ahead of time with input from gdaddy. I have never shaped one. Gonna have to see if I can take one of those junk Echotech longboard blanks I've got laying around and see it I can do one from scratch. Rocker,foil et. all.
That which can be assorted without evidence was read in an illegal magazine.
I'm with gdaddy on the fins. Fins have come a long way since the keel era. But if you like them, that's all that matters.
However, one of the original design elements that Lindsey Lord used in his planing hull testing was parallel sides. He found that to be the key to speed. Of course surfboards are different and need some curve in the outline, but if you will look at some of the earliest mini sim's you see a more parallel rail shape. He further found that there is an optimal ratio of length to width that results in better speed.
I've read that Lord's design was used by whisky runners during prohibition and later used for military landing craft. There's a bunch of info to read out there.
Your rails seem much more curvey to the eye. If you are happy with it, great. But if you want to tinker a bit, maybe consider more parallel rails.
Good luck and keep posting.
all the best
Personally I'm always ready to learn, although I do not always like being taught. - Winston Churchill
Do you remember that optimal length:width ratio?
Swaylocks Surfboard Design Forum: thoughts & theories ... practical & theoretical
RAIL PROFILE http://bgboard.blogspot.com/2014/03/march-82014-afterr-seeing-recent.html
Naval architect Lindsay Lord said the most common factor in a good planing hull was the width in the stern. If you divide the width into the length you’ll get the Aspect Ratio. It will be a decimal number. Good numbers are .3 to .5.”
No; It's not an ironing board.
Thanks unclegrumpy. I was just now looking in my notes. When you assume a max usable width of say 23 inches, at .4 AR you end up with a board length of 57.5 inches. A little small is for most ppl. At .3 AR and say 22 inches wide you could be at 73 inches long. All of which says to me that mini sims need to be really short to maximize speed. And of course that helps with maneuverability. Back foot right at the back edge of the board (where the fins should be set) and then you can whip it around like a skateboard. A mini sim will stiffen up really fast when you lengthen it to regular short board dims. Just my 2 cents.
all the best, boys,
The original Simmons boards were designed to go fast and straight. And they'e quite long in relation to their overall width and tail block width. But what they do have going for them is the large wetted surface area and the long straight rail line because after all, even "straight" isn't really straight or flat in surfing. Even those boards are using their long rail lines to contribute to their drive.
Those keels at the corners probably don't do anything more than add stability, hold and control. Heck, as far as hold goes, the round shape of the moon keels would release less than a keel or fin with a smaller tip. Good for going straight, but nor so good for turning.
All true. L
My youngest son is a longboarder and a heavyweight. One of his boards is an 8ft Simmons. I didn't build it, one of our freinds built it. That thing is a total beast. I've seen him run down paddleboards with it. It's got so much float and is so straight that I can't generate enough leverage to turn it because I'm just not big enough. Set a rail and everyone down the line better get out of the way because it runs like a freight train. Not my thing, at all.
I love that, gdaddy