...Fin Box Idea...

…I’m thinking of modifying a standard 10" fin box…I see the weakest part of the system, as the tab with the screw hole…My wide base wood fins have a tab that is more fragile than a solid glass fin…Also the standard box isn’t designed very well to accomodate fins thicker than 3/8"…A wider fin has to have the tab at the trailing edge to get it to drop in the box… Also the depth of the box into the blank is not consistant, add to that tail rocker, and a heavy or light sander and you have a lot of variables… …What if…a standard box was tapped to take advantage of the FCS set screw mathod…Maybe set scews on both sides of the box, 2" o.c… …With that set-up, a fin would not need the pin or the screw tab, it would just have to be 3/8" thick where it fits the box…The fin could also be made to set back over the ends of the box, expanding the range of fin placement… …What do you think… Paul

I jumped early on the wagon when it came to the fcs longboard set up. Basically, 6 plugs in a row with a 4 tabbed fin (which gave you some placement options). After about 3 boards I found out for myself and from others that there is just to much torque/stress to hold in a fin, let alone if you hit the fin with your body or the bottom (I’m talking about single fins and 2 + 1 setups). Your idea would probably work if you increased the number of screws into the box and maybe configured it so that the screws were placed on either side of the box all the way down ( ::::::::::::: ). As opposed to the staggered fcs approach. I guess the key is to get enough pressure on the fin to secure it well without adversely tweaking your fin alignment to the bottom of the board. Good luck. By the way, your paddle board and fins look way good. Keep up the great work.

…I’m thinking of modifying a standard 10" fin box…I see the > weakest part of the system, as the tab with the screw hole…My wide base > wood fins have a tab that is more fragile than a solid glass fin…Also > the standard box isn’t designed very well to accomodate fins thicker than > 3/8"…A wider fin has to have the tab at the trailing edge to get it > to drop in the box… Also the depth of the box into the blank is not > consistant, add to that tail rocker, and a heavy or light sander and you > have a lot of variables…>>> …What if…a standard box was tapped to take advantage of the FCS set > screw mathod…Maybe set scews on both sides of the box, 2" o.c…>>> …With that set-up, a fin would not need the pin or the screw tab, it > would just have to be 3/8" thick where it fits the box…The fin > could also be made to set back over the ends of the box, expanding the > range of fin placement…>>> …What do you think… An angled set screw design to secure fins in a box relies heavely upon point loading. You have stainless steel tips pushing against fiberglass or plastic that a very small surface area. All the loads transfer directly at those points. The fin material breaks down and the fin gets sloppy. Single fins have longer lever arms so they transmit more load. So, you will need to tighten your set screws frequently take up the deformation slack. The threads the set screws cut into the box are only as strong as the plastic of the box. Consequently after repeated tightenings the threads strip out. One of the key design characteristics of Red X is that we maximize the intiment contact area between the box and the fin. The mating taper between the super tough material of the box and the fin distrubute the load over more surface area between both the bottom of the board and the deck. Consequently, you get a secure fit that does not need constant readjustment.>>> Paul

…I’m thinking of modifying a standard 10" fin box…I see the > weakest part of the system, as the tab with the screw hole…My wide base > wood fins have a tab that is more fragile than a solid glass fin…Also > the standard box isn’t designed very well to accomodate fins thicker than > 3/8"…A wider fin has to have the tab at the trailing edge to get it > to drop in the box… Also the depth of the box into the blank is not > consistant, add to that tail rocker, and a heavy or light sander and you > have a lot of variables…>>> …What if…a standard box was tapped to take advantage of the FCS set > screw mathod…Maybe set scews on both sides of the box, 2" o.c…>>> …With that set-up, a fin would not need the pin or the screw tab, it > would just have to be 3/8" thick where it fits the box…The fin > could also be made to set back over the ends of the box, expanding the > range of fin placement…>>> …What do you think…>>> Paul First off Paul, I have much respect for you ability as an artisan and craftsman. I have the same experience with fin boxes. On boards with thick tails the boxes are all about the same so it’s not too big a deal making fins to fit. On my new 7’9’ the box is thinned down because of the tail design. So fitting fins to the box is a little more delicate matter than I had expectec but wasn’t really that bad. As to thicker fins-- (I’ve got some out on test on tow in boards, which will put them to the ulitmate test) I feel there is merit in making them, feeling there is much room for this type of foil in the future of surfboard performance. I don’t use wood but have a few ideas to share. but you never know when the request will come through If I were going to make a thicker fin with wood, say an 8" fin with some a fair amount of surface area I’d start with a carbon/glass or glass only epoxy core of about 8to 10 layers I’d put a glass epoxy shell around the wood as well. Epoxy is the choice when strength is the issue. The core and the shell intergrated with the tab will give the fin sufficient structural strength and all you have to do the make the tab work is to extend it out beyond the front of the fin a little so you can tip it up when inserting it into the box.(All puns intended!) I don’t think there’s very much stress on the anchor screw as it only serves as a locater. The serious stress is on the fin side to side depending on the surfer and the fin area. Assymetrical rail fins take the most stress on flips and roundhouse cutbacks. Keeping fins light and foiled to serve performance continues to be an ongoing challenge. The fin box idea may be more trouble than it’s worth but without experimentation how do we learn anything? Glad to chat anytime-- reach me at Gone Surfin’, Rich

…Will Red X accept custom fins, like mine…??? Paul An angled set screw design to secure fins in a box relies heavely upon > point loading. You have stainless steel tips pushing against fiberglass or > plastic that a very small surface area. All the loads transfer directly at > those points. The fin material breaks down and the fin gets sloppy. Single > fins have longer lever arms so they transmit more load. So, you will need > to tighten your set screws frequently take up the deformation slack. The > threads the set screws cut into the box are only as strong as the plastic > of the box. Consequently after repeated tightenings the threads strip out.>>> One of the key design characteristics of Red X is that we maximize the > intiment contact area between the box and the fin. The mating taper > between the super tough material of the box and the fin distrubute the > load over more surface area between both the bottom of the board and the > deck. Consequently, you get a secure fit that does not need constant > readjustment.

If you build your fins like Mike suggested, you could make them fit. I could send you a root alone that would give you the basic geometry. I have broached a few custom fins for Dev. True Aimes & Fiberglas Fin Co. both make laminated fins that fit our boxes. I have a 7" True Aimes center fin in my Bonzer. A problem with Red X for a single fin center fin box is the short range of movement. So, you need to know where you are planning on keeping your fin. In the future will will make a box with more range. Currently, we have been focusing on Thrusters, Twins and now Bonzers. We do have two 2+1 side bites available and a plug to fit the holes when not in use. But, we have not had the time to make a box with longer range for single fins.

If you build your fins like Mike suggested, you could make them fit. I > could send you a root alone that would give you the basic geometry. I have > broached a few custom fins for Dev. True Aimes & Fiberglas Fin Co. > both make laminated fins that fit our boxes. I have a 7" True Aimes > center fin in my Bonzer. A problem with Red X for a single fin center fin > box is the short range of movement. So, you need to know where you are > planning on keeping your fin. In the future will will make a box with more > range. Currently, we have been focusing on Thrusters, Twins and now > Bonzers. We do have two 2+1 side bites available and a plug to fit the > holes when not in use. But, we have not had the time to make a box with > longer range for single fins. Sorry, that was Rich with the Laminated Core build schedule not Mike. My bad!

…I’m thinking of modifying a standard 10" fin box…I see the > weakest part of the system, as the tab with the screw hole…My wide base > wood fins have a tab that is more fragile than a solid glass fin…Also > the standard box isn’t designed very well to accomodate fins thicker than > 3/8"…A wider fin has to have the tab at the trailing edge to get it > to drop in the box… Also the depth of the box into the blank is not > consistant, add to that tail rocker, and a heavy or light sander and you > have a lot of variables…>>> …What if…a standard box was tapped to take advantage of the FCS set > screw mathod…Maybe set scews on both sides of the box, 2" o.c…>>> …With that set-up, a fin would not need the pin or the screw tab, it > would just have to be 3/8" thick where it fits the box…The fin > could also be made to set back over the ends of the box, expanding the > range of fin placement…>>> …What do you think…>>> Paul I’ve never liked the way std fin boxes work. Seems to me that if you wanted to modify a standard box (rather than start from scratch) you could change the basis of the design to a different attachment system, say pinned rather than tabbed & screwed. If you drilled a series of holes through the bottom of the box then epoxied in a vertical line of clevis pins (or something like that) at some interval (2 inch?) – then you’d have to have a matching series of holes (vertically aligned) in the base of your fin, and a longitudinal hole through which to fish a wire/rod to lock the whole thing together. Depending on the expected size of and load on your fin, the pins could be long (more strength) or short (lighter). Might cost a few bucks for the hardware but it would be fun to try…

…I’m thinking of modifying a standard 10" fin box…I see the > weakest part of the system, as the tab with the screw hole…My wide base > wood fins have a tab that is more fragile than a solid glass fin…Also > the standard box isn’t designed very well to accomodate fins thicker than > 3/8"…A wider fin has to have the tab at the trailing edge to get it > to drop in the box… Also the depth of the box into the blank is not > consistant, add to that tail rocker, and a heavy or light sander and you > have a lot of variables…>>> …What if…a standard box was tapped to take advantage of the FCS set > screw mathod…Maybe set scews on both sides of the box, 2" o.c…>>> …With that set-up, a fin would not need the pin or the screw tab, it > would just have to be 3/8" thick where it fits the box…The fin > could also be made to set back over the ends of the box, expanding the > range of fin placement…>>> …What do you think…>>> Paul Try Thane Pope at Pope Bisect.He showed me a new box system his dad developed that doesn’t use screws,etc. and allows for thicker fins.

This will sound odd, but go to a surf museum or shop that has a few 60s & 70s boards. Look at the removable fins of that era. W.A.V.E. Set, in particular. I have a long board that I installed an old W.A.V.E. box in, with the original 12" fin. It takes lot of abuse, including grounding(that’s a long fin!). The company went out of business maybe 25 years ago or so, but I understand that someone bought thier dies and are starting to produce them again, mostly for restoration purposes. These boxes are tapered, vertically, for a snug fit. They have nuts molded into them and 2 set screws that go throught the fin, one in front and one in back. Thay are also thinner in the back, to accomidate the taper of the board.

Try Thane Pope at Pope Bisect.He showed me a new box system his dad > developed that doesn’t use screws,etc. and allows for thicker fins. …and to contact him…??? Paul

…and to contact him…???>>> Paul or fax 760-268-1067.hope that works for ya!