Rob I ran quickly through the posts below on the experimental flexie flyer you want to try. So I thought I’d throw some thoughts together as I too have tried to travel this rocky path. 1) My forays into flex ended up in two basic camps; rocker flex along the stringer (flex tail: rail and stringer rocker flex equally) and rail rocker flex (Velo flex, variable “V” flex: stringer rocker does not flex but rail rocker does). 2) The variable V (I’ll call it v flex from this point on) does not work well with multiple fins as the cant will change with flex. It seemed to work the best for standing as you could keep large amounts of foam in the tail and still get it to flex. It was the hardest to fix/modify during trials though. Foot placement was not that important. 3) Flex tail was the easiest to build and modify. Single fin worked the best but the only multi-fin configuration I tried was a twin with no cant or toe. The flex tail was extremely sensitive to foot placement so the only really successful one I rode was a displacement hull flex tail. You stood in the center of the board to turn it so you stayed away from the flex panels. 4) It’ll drive you nuts… 5) If you are really serious about fooling with this, I’ll give you some tips: a) Do it systematically. Rob, you’re starting with too many variables. You’ll never figure out which wiggle is good and which is bad. b) Shape a nice simple outline that’s easy to reproduce(make it a couple of inches longer and and inch wider than you’d usually make). Give it a simple rocker and no bottom contours. Make two. c) Ride them until you know them both well. Modify one to flex (Start at the tail or tail corners and work toward the nose). Just little pieces at a time. Ride it and write down your impressions. Be as specific as possible so you can compare it with future modifications. Always ride the non-flexer the same session so you can make an honest comparison. Why start with a tri-fin? It is already an extremely maneouverable design that is dependent on the interaction between the fins and rear foot placement. Why not start with a really stiff design that can be made as maneouverable as the tri-fin by manipulating the rocker? Surfing a tri-fin requires weighting and unweighting through the turn (pumping) which is just the opposite of the flexiboard turns that worked best for me (keep it weighted and roll off the radius at the end to alow the flex to rebound). Flexi-turns are smooth carves. As I ran out of money and time to maintain my habit, I bid farewell to flex and joined the ranks of the mortals. My failures were more the result of material failure than design. My successes were too expensive and time consuming to repeat. Go for it Rob…you’ve got the right combination of waves, talent and attitude. If you want some more details, contact Mike P. and he’ll give you my e-mail address… In my opinion, the future of flexible surfcraft is already here…you just have to blow them up before you paddle out. Newbs
Rob>>> I ran quickly through the posts below on the experimental flexie flyer you > want to try. So I thought I’d throw some thoughts together as I too have > tried to travel this rocky path.>>> 1) My forays into flex ended up in two basic camps; rocker flex along the > stringer (flex tail: rail and stringer rocker flex equally) and rail > rocker flex (Velo flex, variable “V” flex: stringer rocker does > not flex but rail rocker does).>>> 2) The variable V (I’ll call it v flex from this point on) does not work > well with multiple fins as the cant will change with flex. It seemed to > work the best for standing as you could keep large amounts of foam in the > tail and still get it to flex. It was the hardest to fix/modify during > trials though. Foot placement was not that important.>>> 3) Flex tail was the easiest to build and modify. Single fin worked the > best but the only multi-fin configuration I tried was a twin with no cant > or toe. The flex tail was extremely sensitive to foot placement so the > only really successful one I rode was a displacement hull flex tail. You > stood in the center of the board to turn it so you stayed away from the > flex panels.>>> 4) It’ll drive you nuts…>>> 5) If you are really serious about fooling with this, I’ll give you some > tips:>>> a) Do it systematically. Rob, you’re starting with too many variables. > You’ll never figure out which wiggle is good and which is bad.>>> b) Shape a nice simple outline that’s easy to reproduce(make it a couple > of inches longer and and inch wider than you’d usually make). Give it a > simple rocker and no bottom contours. Make two.>>> c) Ride them until you know them both well. Modify one to flex (Start at > the tail or tail corners and work toward the nose). Just little pieces at > a time. Ride it and write down your impressions. Be as specific as > possible so you can compare it with future modifications. Always ride the > non-flexer the same session so you can make an honest comparison.>>> Why start with a tri-fin? It is already an extremely maneouverable design > that is dependent on the interaction between the fins and rear foot > placement. Why not start with a really stiff design that can be made as > maneouverable as the tri-fin by manipulating the rocker? Surfing a tri-fin > requires weighting and unweighting through the turn (pumping) which is > just the opposite of the flexiboard turns that worked best for me (keep it > weighted and roll off the radius at the end to alow the flex to rebound). > Flexi-turns are smooth carves.>>> As I ran out of money and time to maintain my habit, I bid farewell to > flex and joined the ranks of the mortals. My failures were more the result > of material failure than design. My successes were too expensive and time > consuming to repeat.>>> Go for it Rob…you’ve got the right combination of waves, talent and > attitude. If you want some more details, contact Mike P. and he’ll give > you my e-mail address…>>> In my opinion, the future of flexible surfcraft is already here…you just > have to blow them up before you paddle out.>>> Newbs Brother … have fun
Wow this is good stuff i just can’t believe all the different design ideas that have been brought to my attention. i’m going to go thru what you wrote and recap some ideas of my own. I’m very open to single fin design even 2/1 shortboard design. running small side fins and a short flex in back???>>> Rob>>> I ran quickly through the posts below on the experimental flexie flyer you > want to try. So I thought I’d throw some thoughts together as I too have > tried to travel this rocky path.>>> 1) My forays into flex ended up in two basic camps; rocker flex along the > stringer (flex tail: rail and stringer rocker flex equally) and rail > rocker flex (Velo flex, variable “V” flex: stringer rocker does > not flex but rail rocker does). >>>>>>>>>>>>>>>>>>. Sounds right do you think shaping a bit flater rocker then norm would be the way to go?? So as the board did flex it would bend to true rocker ( that being what i would put in my standard board??? Not knowing how much flex i will reach thru a turn it’s hard to know much flater i want the bottom rocker???>>> 2) The variable V (I’ll call it v flex from this point on) does not work > well with multiple fins as the cant will change with flex. It seemed to > work the best for standing as you could keep large amounts of foam in the > tail and still get it to flex. It was the hardest to fix/modify during > trials though. Foot placement was not that important.>>>>>>>>>>>>> It sounds like you worked with kneeboarders some??? Cause you say it worked best with standing the two Design are so different. I’m sure the tri worked real good as long as there isn’t to much flex. Which on a standard shortboard i would be happy to get 3/4" of flex on a 14" tail at the tip of the SW… What i gain with release as the board loads up with flex would and if i get 1/2" twist i think should be enough snap… With so little change in cant the tri should be fine I hope… As i don’t see myself shaping that much foam out of the tail. The foam will roll into the flex as a fin layup would but without the rope just foam. I think that blending of the foam will help keep a uniform flex along the bottom.>>> 3) Flex tail was the easiest to build and modify. Single fin worked the > best but the only multi-fin configuration I tried was a twin with no cant > or toe. The flex tail was extremely sensitive to foot placement so the > only really successful one I rode was a displacement hull flex tail. You > stood in the center of the board to turn it so you stayed away from the > flex panels. >>>>>>>>>>>> It seams in the early days we wanted a board to snap out of turns more then they did in the 70’s single fins… Now we want more drive which we lose some of going to tris. I think Rustys got the right idea by new standards we don’t need the flex we once wanted. Short light boards only need small amounts of flex to gain the extra snap. That gives these new designs a added feel…>>> 4) It’ll drive you nuts…>>>>>>>>>>>>>>>> IT ALREADY IS!!!&%$^&$%(&*+=singletwisting flex &(^)_)_0 Keep it simple as i can i keep telling myself that…>>> 5) If you are really serious about fooling with this, I’ll give you some > tips:>>>>>>>>>>>>>>>>> >>>>>>>> Keep it simple???>>> a) Do it systematically. Rob, you’re starting with too many variables. > You’ll never figure out which wiggle is good and which is bad. >>>>>>> I agree there and i have a few friends that ride same size as me so we all can go out and switch around boards… There stoked boards to ride and they didn’t have to buy them?>>> b) Shape a nice simple outline that’s easy to reproduce(make it a couple > of inches longer and and inch wider than you’d usually make). Give it a > simple rocker and no bottom contours. Make two. >>>>>>>>> Why so much bigger??? I’ve bounced around between 6’0 and 6’2 both in the 18 1/2 range to go 19 1/2 wide i can’t maybe 18 3/4 but only if i went with a tri hull style bottom. You said no bottom contours on that small of a board i need a bit of lift to balance out the thin 2 to 2 1/8 design. the guys that would ride and myself we all weigh about 165 to 175… Rocker like i said i’m thinking about shaping a little less thru the bottom back 2/3…>>> c) Ride them until you know them both well. Modify one to flex (Start at > the tail or tail corners and work toward the nose). Just little pieces at > a time. Ride it and write down your impressions. Be as specific as > possible so you can compare it with future modifications. Always ride the > non-flexer the same session so you can make an honest comparison. >>>>>>> I want to make 4 thats why i ordered two standard rusty blanks and two cut only half way thru. with full stringers of spruce. I will cut the stringers so the tail will flex more thru the back 2/3 it would be nice to make a standard model with no flex to compare to also… I’m just glad i’m not paying full price for all this. This stuff is why i started building boards.>>> Why start with a tri-fin? It is already an extremely maneouverable design > that is dependent on the interaction between the fins and rear foot > placement. Why not start with a really stiff design that can be made as > maneouverable as the tri-fin by manipulating the rocker? Surfing a tri-fin > requires weighting and unweighting through the turn (pumping) which is > just the opposite of the flexiboard turns that worked best for me (keep it > weighted and roll off the radius at the end to alow the flex to rebound). > Flexi-turns are smooth carves. >>>>>>>>> My point the new designs of the last 12 years thin and light do manouver well but still could use a bit of added snap in small mushy waves…I can see the benifits of more flex in a single fin to sling shoot you out of turns. Now add a little bit more snap out of a Extremely quick board is a plus…>>> As I ran out of money and time to maintain my habit, I bid farewell to > flex and joined the ranks of the mortals. My failures were more the result > of material failure than design. My successes were too expensive and time > consuming to repeat… >>>>>>>>>>>> I understand how it could drive a shaper into the poor house but if it works???>>> Go for it Rob…you’ve got the right combination of waves, talent and > attitude. If you want some more details, contact Mike P. and he’ll give > you my e-mail address… >>>>>> >>>Mike Please hook me up… if not just pop into my site below and send me a message…>>> In my opinion, the future of flexible surfcraft is already here…you just > have to blow them up before you paddle out…>>>>> >>>>>> I agree i could learn alot about flex on a mat… I wish i could afford one to ride at the cove…>>> Newbs Thanks a ton you gave me a few things to think about…Single Fin? Rob http://surfnwsc.com
I’m very open to single fin design > even 2/1 shortboard design. running small side fins and a short flex in > back??? Rob, Greenough went through a brief 2 + 1 phase back in '72, but eventually went with a straighter tail outline (like a fish) with a single fin, rather than a curvier arc tail with small side bites. At the time, he said that there were simply too many variables with multiple fins to ever really reach the concept’s full potential. The much straighter tail provided the stability of the side fins, and the soft flex of the corners provided the looseness. As we talked about earlier in the week, kneeboards and surfboards are profoundly different, so comparisons have to be tempered. But, since he has taken the flexibilty aspect of board design to it’s highest level, by far, I think it’s worth talking about his experiences. There’s another way to look at what you’re intending, and that would be to say that maybe what you want is a livelier board. This would follow in the footsteps of the first Yater Spoons, or Liddle’s stringerless hulls with thin rails and tails. Flex was there to a degree, but liveliness and sensitivity would be a more accurate way to express what was taking place.
Rob: You need to figure out where you want to go before you start off…If you want to take an known design and add some flex to see what happens, great. It’ll be fun and, in the short term, enlightening. But you won’t be able to apply it to new designs without going through trial and error process for every new shape, length, or fin configuration. Having gotten a science and engineering education after ceasing my “flexperiments”, I’ve realized that I would have benefited more by using a systematic approach. This avenue is time consuming, boring and won’t yield immediate results, but, in the end, you’ll really know if flex has its place and where. The engineering approach is to isolate the effect so that you can study what happens when you modify it. Take one aspect of the board and add flex. For instance, scoop out the foam behind the rear fin all the way from rail to rail. See what it does. Now make it stiffer and see what it does. Stiffen just the rail sections and see what that does. Stiffen the stringer and see what it does. Now expand the flex pannel to include the rear fin. Etc., etc. Thats why I suggest a real simple outline and rocker…you just want to screw with the flex pannel and not worry about anything else. It could take a month just to get the first set of variables sussed (that is, if there is surf!). What effect does the size and shape of surf have on the design? More variables!!! (Here’s a way to speed it up…do you have a friend with a boat and access to a lake or river? Tow behind a boat going between 5 and 12 mph. The turns will be the same as in the surf and cutting will approximate trimming along a wall. That why a suggested a longer, wider stick) I dabbled in both stand up and kneelo platforms and they don’t compare well. George’s Velo was 5’long but over half that length contained George’s shins and knees. On a stand up platform you have two point loads that can move around so the physics are sooo diferent. Do I have any conclusions? None of the boards I made or rode snapped out of a turn. It was more of a bwang, even with the stiffest flex. The stand-up flex tail felt best in mushy walls where it would liven up the performance. The variable v (only made stand-ups with this feature) was the most predictable and if I was to screw with this stuff again, I would apply it to a flat rockered longboard or mini-mal (maximum trim speed…step on the tail and it would turn like a mother). Volan will flex longer without fatigue. The areas where flex panels attach to foam are the weak point. Foam will crush and things will fall apart quickly (I never really figgered how to overcome this, it is a torsion box so you have to account for changes in volume as the flex occurs). Don’t let any of this dissuade you…I hope you take the rougher road of research rather than playing around but it’s all good. I’ll check your web site and get your fax #. I can send you some sketches of the stuff I fooled with. Unfortunately, I’ve got no photos and the evidence is buried in landfills across California… Newbs
You know your right i should walk before i run with it but??? I’m going for what i feel will work and make changes as i go. I mean you have to go Eddie did… I’ll have up dates to let those who live outside the box a look. Thanks a bunch…Rob PS>>> got your e’mail send me the X-files…>>> Rob:>>> You need to figure out where you want to go before you start off…If you > want to take an known design and add some flex to see what happens, great. > It’ll be fun and, in the short term, enlightening. But you won’t be able > to apply it to new designs without going through trial and error process > for every new shape, length, or fin configuration.>>> Having gotten a science and engineering education after ceasing my > “flexperiments”, I’ve realized that I would have benefited more > by using a systematic approach. This avenue is time consuming, boring and > won’t yield immediate results, but, in the end, you’ll really know if flex > has its place and where.>>> The engineering approach is to isolate the effect so that you can study > what happens when you modify it. Take one aspect of the board and add > flex. For instance, scoop out the foam behind the rear fin all the way > from rail to rail. See what it does. Now make it stiffer and see what it > does. Stiffen just the rail sections and see what that does. Stiffen the > stringer and see what it does. Now expand the flex pannel to include the > rear fin. Etc., etc. Thats why I suggest a real simple outline and > rocker…you just want to screw with the flex pannel and not worry about > anything else.>>> It could take a month just to get the first set of variables sussed (that > is, if there is surf!). What effect does the size and shape of surf have > on the design? More variables!!! (Here’s a way to speed it up…do you > have a friend with a boat and access to a lake or river? Tow behind a boat > going between 5 and 12 mph. The turns will be the same as in the surf and > cutting will approximate trimming along a wall. That why a suggested a > longer, wider stick)>>> I dabbled in both stand up and kneelo platforms and they don’t compare > well. George’s Velo was 5’long but over half that length contained > George’s shins and knees. On a stand up platform you have two point loads > that can move around so the physics are sooo diferent.>>> Do I have any conclusions? None of the boards I made or rode snapped out > of a turn. It was more of a bwang, even with the stiffest flex. The > stand-up flex tail felt best in mushy walls where it would liven up the > performance. The variable v (only made stand-ups with this feature) was > the most predictable and if I was to screw with this stuff again, I would > apply it to a flat rockered longboard or mini-mal (maximum trim > speed…step on the tail and it would turn like a mother). Volan will flex > longer without fatigue. The areas where flex panels attach to foam are the > weak point. Foam will crush and things will fall apart quickly (I never > really figgered how to overcome this, it is a torsion box so you have to > account for changes in volume as the flex occurs).>>> Don’t let any of this dissuade you…I hope you take the rougher road of > research rather than playing around but it’s all good. I’ll check your web > site and get your fax #. I can send you some sketches of the stuff I > fooled with. Unfortunately, I’ve got no photos and the evidence is buried > in landfills across California…>>> Newbs http://surfnwsc.com
You know your right i should walk before i run with it but???>>> I’m going for what i feel will work and make changes as i go. I mean you > have to go Eddie did… I’ll have up dates to let those who live outside > the box a look.>>> Thanks a bunch…Rob>>> PS>>> got your e’mail send me the X-files… You flex tail guys are out of the box allright…way out man.I am currently wondering about the flex factor in my lampshade design project…R.B.