So when I got into the shop today I did a “stress” flex test on the rail test samples I had laying around. Two rails off the same test blank(a cnc cut blank so the rails are virtually the same). Put a square against the wall. Put the blank against the wall and bent the tail from center. Like a dummy I left my notes at work(it’s Friday afternoon and all), but it bent about 9.5 inches until it failed. Did the other blank with a slightly different layup dimension. It bent just about the same until it failed. I then started to like the breaking stuff theme so I took another of the same size and shaped machined blank rails I had laying about. Thankfully it’s hard for me to throw stuff like this away. It may some day come in handy. Well I bent a plain EPS section until it failed. It failed somewhere around 16" or so. It was much more flimsy than the carbon rail as well.
All this was done with only the rails layed up with the carbon. No other glass was on the board and it was in half secton.
By the time failure occurs I think the board would stall out it not be an issue or it would be a very heavy situation where board failure is the least of ones worries. As far as the Aviso comparison of hollow carbon rails with a two piece molded product failing…it’s comparing apples and oranges.
Another comment of cutting the rail and putting in a stringer piece to complete the rail structure. I’ve thought alot about that one but can’t think of a really easy way to get the carbon in there(wood stringers would be easy but time consuming).
I’m trying to get a production friendly “tech” type board.
Probably best for another post, but I mentioned it in a rambling reply to Silly. This is a double concaved deck I’ve been doing with good results with good ol’ Pu/Pe construction. Trying to stiffen up the flex response. Seems to accomplish many things at once.
What I origonally meant - shape the blank, put the carbon on and cut the blank at the edges of the carbon (with a regular saw) finish encasing the rails in carbon and re-attach them.
What I just thaught of - Cut off the rails of the board (how ever much you want to cover in carbon) encase them in carbon then re-attach them. This way it is one pice of carbon.
It may go back together easier if you cut them off at an angle.
If this works exceptionally well, all I ask for is one of the boards with said carbon rails.
to compare to those things you would need to have a far thicker wall
look hydro epic
countless dollars on a carbon hollow rail design
that kept failing
Hydro Epics didn’t fail because they had carbon rails… the ones that failed were due to QC issues. The boards that snapped did so because the rails collapsed first. That usually happened because the deck and bottom halves weren’t joined properly. The seam would fail, the rails would flatten out, and the board to fold. I’ve snapped more Hydro Epics than anyone… a lot of them while they were in my hands. I rode an Aviso a few days ago. It did similar stuff under water - deformed due to forces coming from all over.
Tim’s carbon rails are a different animal. The foam will keep them from collapsing, and they will stiffen the board up. I think it’s a cool concept… a cheap and simple way to add some stiffness around the perimeter.
You could shape three new boards in the time it would take to cut the rails, wrap them in carbon (so you have a box), and reapply them. Maybe more.
The problem with ultra complex surfboards is… simply made ones work great.
I think that you could easily go one step further and get an aerospace engineer that surfs involved. Find out how much deflection, load, and duty cycles that you are expecting. With that info he should be able to recommend a specific type of carbon or perhaps another material for the rails. It really isn’t much different than a wing on a plane.
Hydro Epic stopped production a few weeks ago. They ran out of cash just as they were starting to make consistantly good boards. We’ll see if they’re able to pull it back together.
Their rails consisted of four layers of 7 oz carbon and two layers of 7 oz carbon/kevlar. They were plenty strong when glued together properly. We tried using foam in the rails. While it helped hold the shape of the rails, the boards got too stiff and the foam seriously reduced the liveliness of the boards.
On their newest molds, they moved the seam from the board’s equator to the deck. This is something we talked about in the very begining, but it took them four years to incorporate. This makes joining the parts easier, and moves the weak link to a less critical part of the board.
After nearly four years of testing, Al Merrick launched their line of Hydro Epics. Steve Walden’s sales were going strong, and they were having some success with the Hynsen fish. Hydro Epic’s problem was they couldn’t make boards fast enough (and cheap enough) to make money. The motto was (my motto there anyway) “we lose money on every board, but we make up for it in volume”.
Foam and fiberglass surfboards are so easy to make… no complex methods needed… you can have a finished board the next day… and they work great. That’s the beauty of Tim’s idea… simple.
Their rails consisted of four layers of 7 oz carbon and two layers of 7 oz carbon/kevlar. They were plenty strong when glued together properly. We tried using foam in the rails. While it helped hold the shape of the rails, the boards got too stiff and the foam seriously reduced the liveliness of the boards.
Hey Kendall,
Sounds like the problem there is that HE was shooting for the moon.
Just how much more liveliness does the avg punter need?
Why not release a profitable product first, then develop second generation stuff with the some of the profits invested into R&D?
Im disappointed that things arent working out for HE.
Sounds like the problem there is that HE was shooting for the moon.
Just how much more liveliness does the avg punter need?
Why not release a profitable product first, then develop second generation stuff with the some of the profits invested into R&D?
Im disappointed that things arent working out for HE.
Youre sooo right…simple made boards do work good.
The real problem was the original founders weren’t surfers. They were sailboat racers. Millionaire yachtsmen are a different breed than surfers. $1200 molded boards are a hard sell to grubby surfers who are always looking for pro-deals (I’m in that camp). The best guys are looking for deals on custom boards made just for them. Plus the industry trend is towards boards made more cheaply (china) and sold for higher (deserved) margins.
The other problem is… there’s nothing wrong with foam and glass boards. They work great, can be totally custom, and are simple to make. There’s maybe $150 in materials in a poly shortboard. HEs use about $350 in raw materials and take easily four times more labor to make. Then guys label them popouts.
And yet one more problem was a feeling of urgency to get “production” up to speed before all the bugs were worked out. We spent $2 million dollars making LOTS of crappy boards when we should have spent that money carefully refining the process first. We replaced every board that failed over the first couple years, but customers would have rather had ONE board that lasted.
It’s too bad they ran out of juice, because they seemed to finally have the bugs worked out as far as making them goes. Aviso ate up all the scraps. It will be interesting to see how they do.
I like it. Everybody’s still thinking only of flex being logitudinal. This is not the only flex that is important in a board. The rails need to be stiff and the bottom needs to move. Balsa rails achieves this and so does a carbon rail. I agree that a higher density core inside the rail would be of benefit but this construction does answer some performance criteria without getting too complicated. Nice Tim.
Hey Paul, Tim said the carbon-railed blanks failed at 9", without additional exterior glass.
Would you be willing to flex one of your compsands - prior to exterior glassing - to 8.75"?
I wouldn’t
I think the CF is a good, light, predictable material. I bet with pieces of cf wrapped around cut-off rails and then the rails glued back on, you’d have a hell of a light, strong, and lively board. I use CF under balsa wherever I want dent-resistance and it doesn’t add stiffness or weight at all - despite what people say about CF, its a very lively material. People who think its not are really only thinking of mountain bike handlebars and rocket-car hoods and other applications where you stack up more than 1/8" of the stuff. One or two layers is plenty flexible, and way stronger than glasscloth.
I used it on a couple kiteboards, thinking they would be stiffer than others…and had to keep adding e cloth afterwards until they were stiff enough.
Get a chance to flex any unglassed balsa railed Firewire’s yet? Results?
One(Firewire) came in my shop a couple of days ago from a “rep” friend who was going to give it a go. I flexed on it pretty good. Seemed pretty similar to the finished carbon rails I’ve done. I’m sure it can be much different in the water surfing with one side in the water. Water being much more dense than air.
It would be interesting to do the same board(shape wise) both ways(EPS/Carbon and Balsa/Firewire) and see the differences before and after glassing. Be cool to come up woth some kind of flex measuring device that read in pounds of force. I kind of have a working model in my mind, but we’ll see if ever materializes. Torque wrench…So many fun things to do, so little R&D time and money.
Just trying to get as much as I can without changing too much as far as production goes. I want to keep custom and personalized equipment being produced across town, not across the ocean at a reasonable price.
Isn’t one of the main differences structurally between glass and carbon that carbon is “bouncy” or “springy”? Glass returns to it’s shape, but is flexible, not snappy. Carbon when deflected bounces back to shape quite vigorously.
Tim, Surfboards have evolved a certain way and surfing along with it. Boards have always been perimeter weighted. 1/2 the weight in a laminate is in the laps. The deck has always been fairly hard with the most glass and the bottom softer and more flexy with one layer. Since this is the norm and what vitually everyone is used to riding this is what feels best. The FW boards are this exactly this except even a bit stiffer along the rail than a normal PU/PE. People like it because the perimeter weighting and more positive flex gives some real advantages in performance (kudos to Mr. Berger). Durability is a byproduct. What you’ve done here is enhance that same evolution, stiffer along the rail which leads to a more positive flex, perimeter weighting and reduction of performance robbing twist without sacrificing bottom movement. It doesn’t add to durability but for people who aren’t concerned with that it’s a very viable thing. I like it.
Isn't one of the main differences structurally between glass and carbon that carbon is "bouncy" or "springy"? Glass returns to it's shape, but is flexible, not snappy. Carbon when deflected bounces back to shape quite vigorously.
I thought it was kind of the opposite. I remember way back in the late 80’s when I was working for Dencho Marine (builder of custom ocean racing sailboats) we did panel testing. I remember watching them load up the different panels with lead weights. The standard fiberglass panels (they all looked the same to me but I’m sure they were testing E glass, S glass, epoxies, vinylesters…) flexed, then slowly started crackling, and when they failed the were still hanging together with a mass of delamed white fibers.
Then we loaded the carbon panels (different cores and binders). They didn’t flex at all and would carry much more load without significant flex, but when they failed, they failed catastrophically. They literally exploded. BAM. And blew apart.
Incredible material, but its application needs to be studied carefully.
