Hi. I’m trying to shape a Gerry Lopez inspired single fin and am working out the dimensions and everything else. So far I’ve used this previous posts and also a video on youtube:
From the video I can see that Gerry’s finished blank has no tuck at all, and a completely flat deck and no rocker. I’m probably going to keep the rails and deck, but add some concaves and a slightly more modern rocker to help out since it’ll be my step up into 6-10ft waves. There are ways to make it perform better, but I’m really trying to keep as much of the retro look as possible. What would be the performance difference between doing a single into a double concave vs. only a double or only a single concave (and maybe a vee at the end)?
Also from the swaylocks post someone describes these dims to get that retro feel:
Rails turned down all the way up, not thinned, not hard.
Bottom contour flat. Maybe a little Vee, maybe spiral vee. But the earlier ones in the US were flat.
Tail width 13 inches.
Nose width 12 inches.
Tail rocker 1.5-1.75 inches.
Nose rocker 5.5 inches."
I’m wondering if these dims would change much if I shortened the board to 6"3 or 6"5? I’m trying to stick to as close to 30L as possible since that’s what my everyday 5’8" board is right now.
As far as I can tell, the Hawaiians came up with the “tracker” design in order to fit the more extreme conditions some of their breaks have. Big and fast conditions are too fast to surf a shortened longboard design like the Australians started off with in the late 1960s. It’s not a design that really fits the smaller and slower conditions which prevail on the Mainland U.S. But, every break has it’s day so there might be 3 or 4 days a year where you could make a design like this sing.
What I will say about singlefins in general is that (IMO) the engaged rail line is the engine in those designs, not the fin. Unlike with a thruster, all pumping a singlefin does is slow it down. So that means more length and a straighter rail line means more speed. It’s for that reason that thow boards tended to run in the longer lengths. They played around with the shorter lengths under 6-6, but the more successful versions were longer in length.
Personally, I never liked the design for the day-to-day conditions we have in my local. If I was going to build one I wouldn’t even consider doing one at a length of less than 6-8. Everything else being equal, 7-0 would be faster. And you can skip the volume thing; they were not swimming boards into overhead bombs. They were using (by contemporary standards) paddle monster volumes to catch up with the wave.
Here’s a link to the catalog at Surfresearch.com.au, which lays out the general design evolutions over the years. Check out the boards they were doing in the 1970s. There are some shorter lengths but just as one example the 1972 pintail Lopez shaped was an 8ft board.
Thanks for the info! I’m in the Los Angeles SoCal area so there’s plenty of swell where I don’t think finding waves with enough power would be an issue. I’ll move up to either 6’6" or 6’8", and decided to keep everything true to a retro board except for maybe giving slightly more nose rocker (was thinking maybe 4") and maybe a very slight single concave. Would this concave take away from the speed that the board would give if it was flat instead?
I rode those boards and shaped a few myself. They were uncomplicated and pretty easy to shape. Clark during that time frame made one go to blank. I think it was an 8’2. Walk into Mitch’s in La Jolla and they were all the same. That blank made anything from a 7’ thru 8’0. It was best suited for 7’6 which was the most common length. The deck was flat if you left it flat. But, a lot of guys domed the deck. A lot of those boards were “needles”. Hence the description “speed needle”. Essentially those boards were somewhere from an extreme of 17" thru 19" or at most 19 1/2". The averag was 18" thru 19" . 7’6" pulled in tail and nose with a beak. The rail was turned down all the way around. Some were tucked at the middle, but not many. There were very few shapers with the ability or the desire to refine a rail on those boards. Flat bottom and sometimes “V” in the tail. Down the line boards that were fast, but not very mannuverable. Not everybody shaped them like this, but that was the average down rail “Speed Needle” in 1960-70.
Two guys in that thread to which you linked, LeeDD and Blakestah, are well versed in gun design - especially California gun design. They both have contributed loads of data if you dig for it.
It is worth mentioning that the tail width dimension Blakestah recommends is wider than the nose width. This is consistent with what I learned after measuring a few boards in Hawaii in 1972. I was living on a sailboat at the Ala Wai Yacht Club and several people had Lightning Bolts that were ridden frequently at Ala Moana.
Depending on where you intend to ride the board, that particular design feature is worth considering…
I grew up in SoCal, Whittier to be exact, and surfed Baja to Santa Barbara until heading to Santa Cruz for college. Going to Hawaii was a real eye opener. Even minimal swell South Shore was a big step up in speed and power from the best Cali has to offer. The presence or absence of continental shelf makes the difference.
It’s so strange to see the renewed interest in the one design evolution that only really works as intended in the fastest conditions on the planet. There’s a reason this design came up in Hawaii back in the day when surfing was all about getting tubed, and not in Malibu or Rincon where the perfect wave is head high, kinda slow, and runs a couple hundred yards. I predict a year from now we’ll be getting questions on how to add side fins to these narrow singles in order to increase their range and versatility.
I should amend that by saying that there are short singlefin designs that work in slower conditions, but you narrow out a tail when you want to control the energy, not when you want to make more energy.
Those pipeline boards were not good turning boards, they were designed for riding pipe frontside. Bottom rocker was very flat from about the middle on. I still ride a lot of single fin boards, but I prefer them about 7’ or longer. Modern boards are the way they are because they’ve evolved over time. Rockers, rails, bottom contours are very different from the early 70s. As many people learned, boards made for Oahu’s north shore don’t work well in many other places including Oahu’s south shore. Even on the north shore, a Pipe board and a Sunset board will be different because the wave is different.
Gdaddy is correct. I went through several years of making every kind of board shape going back in the past to understand how they work. I did a handful of short single fins and always ended up adding side fins. Here’s a few that went from just OK to a lot of fun.
I tried short performance singlefins a number of times and it would always go the same way; fun under certain conditions but eventually I always went back some months later and added fins out at the rail in order to tap that energy.
The variant I didn’t try but probably should have is adding channels.
Please trust in my decades of experience when I tell you that one of the primary ‘‘engines’’ of a single fin surfboard, is in fact, the fin. A hydrodynamicly foiled fin equals even more horsepower. AKA, speed and performance. I had a real eye opening conversation with Phil Edwards in 1960, about fins. And my subsequent experiences confirmed the truth of what he told me. A fin can make or break a surfboard’s performance envelope.
Having spent a fair bit of time on Liddle style hulls, I can say for certain, once the board itself is “right”, the fin can make it ride anywhere from worthless crap to magic from only tiny changes in template, position, foil, or flex
