Standup Zone Forum
General => The Shape Shack => Topic started by: Beasho on January 09, 2023, 11:05:16 AM
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Let’s Make a Sub 10 lbs SUP Foil board.
I have run the numbers and this should all be possible. There are Pros and Cons
Background:
• Board designs are changing so fast you might pay $1,500 or more and get a board that is obsolete in 6 months
• Figure out how to minimize the investment in ‘Unnecessary’ infrastructure. This includes 1) Material 2) Cost and 3) Weight
• The board does NOT have to last 10 years. The objective might be to have 30 sessions on this board.
• Invest in the Foot area and the TRACKS. BUT Don’t over index on the TRACK reinforcement. I have been a Tuttle advocate since Day 1. For 30+ years Tuttles were the only boxes that wouldn’t rip out of windsurfers. Tuttles go Deck-to-Deck. There has to be some substantial material extending from Deck to Deck. BUT there could be a very light Matrix of foam and carbon rod, with solid top and bottom carbon layer for example that would suitably hold the load for dual tracks.
Estimated Weights of Final boards. This matrix shows the estimates for a board with:
1) Dimensions will be similar to a Barracuda shape 7’ 6” x 22” x 6” around 120 liters
2) XPS Foam: 1.5 lbs per Cubic Foot. Water Proof and therefore MINIMAL intrusion of water from Dings.
3) 1 Layer of 6 oz of Carbon around the entire board. Estimate using a 60% fiber to 40% resin ratio. It will be vacuum bagged. No final gloss coat.
4) Dual Tracks will be added. Ideally 1 lbs of additional weight for the Tracks and necessary structure.
Total IDEAL weight: 8.8 lbs. It will NOT be pretty.
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Additional thoughts: XPS is closed cell foam. It will NOT absorb water. It weighs 1.5 lbs per cubic foot. EPS is lighter but when you get a ding it will absorb water quickly.
There have been several prototype boards in the neighborhood made with XPS. One board did NOT even cover all the XPS but left exposed foam in Non-Critical areas. After 2 years the foam, with little care, started to flake off from chips and/or dings.
I have been testing another approach that would be to GORILLA glue the DRY fiber to the XPS. The objective would be to provide a lightweight jacket to the foam. It would carry load in TENSION only, leaving the fiber attached to the foam but NOT fully wetted out.
Advantages:
1) Ding Prevention. The exposed XPS dings with a fingernail. A test piece of foam with carbon was very durable. Another test piece with 2.7 oz fiber glass also worked very well and was resistant to puncture but much lighter than the carbon sample. (Video to follow).
2) Added stiffness. The thought being to have a light wrap of fiber on the nose and tail to carry load in tension only. Compressive loads would have to be carried by the XPS foam. But the shell of fiber would still be stiffer and more resilient than foam alone
3) The skin material is porous. Some people have experienced delamination related to XPS foam. Because the foam is closed cell ANY moisture that is trapped between the foam and an impermeable skin is at risk of evaporation and delamination. IF the fiber is porous this would significantly reduce the risk of delamination.
Sample XPS with 6 oz CARBON Gorilla glued and vacuum bagged. Pretty slick looking final product. AND pulling out a single fiber was VERY difficult. Meaning the gorilla glue was adhering very well to the closed cell foam.
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Here is a sample of XPS wetted out with Gorilla glue and then laminated with 2.7 oz fiberglass.
The theory is that Fiberglass may be MORE resistant to puncture than carbon. This sample was 2.7 oz so LIGHTER than a 6 oz Carbon for example.
The block of foam weighed 4.81 grams
Fiber added 2.16 grams
Total 6.96 grams
Added a micro layer of gorilla glue and squeegeed off as much as possible.
Final weight: 7.74 grams.
Conclusion: Ratio of Fiber to Resin = 2.16 : 0.78 = 73% Fiber to 27% resin
For the None-Structure / Critical-Heavy-Load-Bearing parts of the board: Outer rails, tail and nose this material could further reduce weight.
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I put a test sample in a bucket of water for 24 hours. Weighed the sample before and after.
It took ~ 1 hour for the sample to dry out to weigh within 1% of the original weight suggesting that the absorption of the closed cell foam was VERY low.
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Very cool ideas, as usual, a sharp left turn from the direction everyone else is taking though that's how things actually progress. Though you're basically reinventing the boogie board. Mr. Morey made some surfboards about 15 years ago that were actually pretty good though they had a hell of a lot of flex. That reminds me, I have to find out where Sol Morey is. Super nice guy, the son of the inventor of foam boogie boards. Sol has the most astonishing balance I've ever seen. Soul Surfer to the tenth power.
I think it's provable that mast tracks glued to light plywood stringers that go top to bottom are as light and strong as any tuttle box. I did a fairly serious test of that when I ran smack into the bunker at Ka'a, flat out. Bent the shit out of an Axis mast base but the board (by Dave Mel) was undamaged.
I think stringers like that complement your idea of all the reinforcement under your feet and around the mast and the rest of the board can be mega-light. I've been thinking that myself for the 8' Kalama-style board I asked Mark Raaphorst to build for me. The long nose and deep canoe hull should be as light as possible. There is XPS available that's lighter than 1.5#, but you have to order it--it's not what they stock at lumber yards. Not cheap, but neither are shaped boards. Greenguard is very strong EPS, I got a 4" X 4' X 8' for about a hundred bucks when I was thinking about building a foil board. It's a bit heavier than some lightweight EPS but it's silly strong even just bare. Not as strong as PVC foam, but in the spectrum between 1.5 EPS and whatever PVC it's probably 1/2 of the way: https://xps.supply/product/kingspan-greenguard-4-x-4-x-8-square-edge-board-insulation-21/
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Here is a ding test on the XPS foam. Using a mechanical pencil on the bare foam vs. the foam with 2.7 oz Fiberglass cloth that has been glued DRY to the surface of the XPS.
The pencil easily dings the bare foam.
But you will see I had to push pretty hard to get the pencil to pierce the material with just 1 layer of fiberglass.
https://youtu.be/xY4QMltT-ZU
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Things are coming together FAST.
My shaping Amigo JOSH said "Come over and Check it out." Josh and KYLE(our local Downwind leader) have a template made out of Masonite.
Thank you! Thank you! Thank you!!!!!!
They are a bit sour on XPS after one of their XPS boards melted in the sun. They are making their versions out of EPS. This one is XPS with SQUARE super boxy rails.
I may just leave it BOXY. They are going to add more chines. I might just round the bottom a little bit and the top for better laminate adhesion (square edges bad).
The current dimensions are:
7' 10" X 21" X 6" Thick
Current Weight 6 lbs 13.8 ounces. Estimated Volume 130 Liters (before any more trimming)
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Potential weight with CLEAN build is estimated at 8 lbs 14 ounces (No deck pad, no handle, leash plug).
All Talk at this point. Feedback Welcome!
You can see the idea is to have 30" of 6 oz Carbon WRAPPING the entire structure. 2X Layers on the top, under foot (I might economize based upon Goofy stance).
Then 1 Extra Layer running Rail-to-Rail from the front to the Back of the Tracks.
More on the Track reinforcement later. But I will be using 1/4" carbon Arrows to handle vertical compressive load. Thinking is 6 arrows biased towards front, and outside each track. 3 on each side of tracks. I have done a version of this with wooden dowels so far without failure.
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I like a lot of these ideas.
Peter J has worked on the box thing. Carbon arrows, or use 1/4" pieces of balsa laminated with carbon like I did. If you want light and not as many dings use 4oz glass everywhere but structural places (nose/tail for example.) Fill it like Peter (and the SF wing guys do) with microballoon paste instead of hot coat. Super light.
There are skinning methods that help waterproof eps (epoxy slurry like Kings, etc)
Don't tell your hippie bay area friends you're building big foam things that may not last long. But yes, this is doable. It's basically a race car construction.
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Keep it simple on the shape....love it! 8oz for the tracks? What tracks will you be using? 16"?
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Peter J has worked on the box thing. Carbon arrows, or use 1/4" pieces of balsa laminated with carbon like I did. If you want light and not as many dings use 4oz glass everywhere but structural places (nose/tail for example.) Fill it like Peter (and the SF wing guys do) with microballoon paste instead of hot coat. Super light.
There are skinning methods that help waterproof eps (epoxy slurry like Kings, etc)
Part of the idea here is that The SKIN will be Porous. IT does NOT have to be waterproof. This eliminates and need for additional fill layers, or microballoons. Finishing a board adds weight, time and cost. Eliminate all 3 with a quick Gorilla glue and Fiber matrix that lets the fabric breath and therefore is LESS likely to delaminate. In theory.
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Can you please explain the ‘carbon arrows’ concept
Thanks
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I love this thread. When I'm out of the OR, I will read it letter for letter.
Carbon fiber arrow shafts are ultralight , very strong carbon tubes designed to withstand compression quite well. They are also pretty strong when flexing and twisting forces are encountered. First, I use them to both attach the boxes to both hull and deck by coring them straight through board(alongside track boxes) and using carbon fiber tow to attach ends to hull, deck and boxes. I use about 3-4 pieces along each track box. Second, Using full length shafts(3-4) run along boxes and forward onto hull prevents that compression failure just in front of track boxes. I only do this on hull since carbon cloth alone does not provide enough compression resistance and creasing can develop from the high cantilevered force. Gotta go back to work. I hope this quick explanation helps.
BTW- Is anybody using Innegra? I love it! It's a very light weight fiber with exceptional strength for ding resistance. 1, 4 oz layer of Innegra cloth covered by 1, 4 oz layer of glass is far more ding resistant than 1 layer of carbon cloth.
One more thing, hollowing out(chambering) structurally insignificant areas (nose, rails, tail) will also decrease weight. I cut out 1.5 lbs of foam from a DW board recently.
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One more thing, hollowing out(chambering) structurally insignificant areas (nose, rails, tail) will also decrease weight. I cut out 1.5 lbs of foam from a DW board recently.
There's a lot of opportunity for hollowing out sections since the most readily available XPS is 2" glued and stacked sheets to achieve the desired thickness.
I've never seen black XPS like that. What's the source?
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Beasho, I get the POUROUS!!!!!!!!!! part. It's done all the time in the Crissy wing crew as you know.
Just contributing an idea for others who might follow this path. I no longer finish my boards with hot coats. I use Peter's slurry method. They still get sealed. They are light as hell. They don't delam. Sanding isn't a pain. Try it guys.
One thing to test. Although the foam won't absorb water, check the weight when you get out. Water retained under the carbon will still likely add more weight than a few grams of resin and microballoons. Would love test results on that if you build one.
Pro tip. Gorilla Glue foamed up can replace K-Y jelly and it's lighter.
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BTW- Is anybody using Innegra? I love it! It's a very light weight fiber with exceptional strength for ding resistance. 1, 4 oz layer of Innegra cloth covered by 1, 4 oz layer of glass is far more ding resistant than 1 layer of carbon cloth.
Yes, everything I build is the same as yours.
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I no longer finish my boards with hot coats. I use Peter's slurry method. They still get sealed. They are light as hell. They don't delam. Sanding isn't a pain. Try it guys.
What's the ratio of epoxy to micro-balloons? Or perhaps you could just describe the consistency of the resulting mixture - more like honey, creamy peanut butter, or spackling compound?
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I go peanut butter now. Not runny. I do squeegee one fill coat on first and then sand it all off/flat.
Squeegee the microballoons and then sand with 220 or even 320 between applications. When I think I've got the pinholes all full I do one more application and then I spray it with primer which shows any last pinholes. Fill em and go, or paint.
If you don't wanna primer it you can rub some resin on it with a gloved hand. When Peter says lean he means lean.
By the second application there's almost no material going on. I can do the whole board with like an ounce of material.
I'm digging my results.
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When I made my last board (4’1” prone) I was thinking of ways to do closed cell foam skins. I’ve done Dcell on 1lb eps but the trouble is how much epoxy it needs to stick, even as a thickened mix. I was thinking gorilla glue would be good except that I can’t really spread it thin evenly on the board quickly, it’s pretty viscous especially for 1lb eps. Pour foam or pour epoxy was my answer and I started a thread on it.
Well after talking to a few crissy guys they just go 1lb eps and do 4 layers of carbon on the deck and one on the nose and wrap rails. Seems like it’s less durable but you will have no problems with dings or delams or boxes coming out of you do it well and avoid hard objects. If anyone can show me how to make it lighter I’m all ears but they are putting out sub 8lb 75L boards including the pads. I think even a 100l 7’3” DW sup under 10 lbs. I’ve done deck sandwiches, standing area sandwich and full board sandwich. Next is just carbon on eps and a patchy white finish job using textreme.
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I've made several boards using XPS and have only ever found delamination issues when using paint over the foam. Thats not to say I am not suspicious of the bond between skin and foam. All the talk of "outgassing" and "oils" from production keeps me somewhat cautious. I have always coated the foam surface with epoxy and micro balloons. Seems to work as far as I can tell, though I would appreciate a lighter weight filler. Maybe just spreading a fine layer of Gorilla Glue over a finely water misted surface (let harden and sand afterwards). Epoxy resin bonds well to PU foam and PU foam bonds well to anything.
On another note, I've got this massive sheet of green, high density XPS (unsure of exact density) from a recent project. I'm going to enlist the help of a 3D CAD modeler friend to help me loft the ribs of a DW board so that I can cut them out, lay them down on a foam stringer, and skin with high density XPS 3/4" sheets, just like the hollow wood board builders do (using Gorilla Glue to bond), only thicker than wood skin. Of course, the box area will be almost solid as well as foot strap insert areas. My theory is if going with far less foam, make sure its dense and strong. Eliminates the need for 1/8" Divinicell and maybe even carbon cloth. This should be a fun project.
Just noticed a question regarding consistency of Micro balloon paste- I like it like All-Natural Peanut butter, it flows if you tip the container, somewhat runny. I also make sure the board is good and warm (for a long time) when squeegeeing it on, and the bring the board out in the cold. This way the resin gets sucked into the pinholes.
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Next is just carbon on eps and a patchy white finish job using textreme.
What's textreme?
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A brand name for spread tow carbon. The same weight and strength fabric will be ~20% lighter or so using that instead of other weaves because the epoxy doesn’t have to fill as many kinks in the carbon weave.
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SUPeter, maybe you have looked but people have built kayaks and SUPs like this before. If you google foam strip kayak there are a few build threads.
As far as the forms you can do it on Shape3D if you have it or know someone with the paid version. There is a hollow board function. Mine expired sorry.
I used a free program called kayak foundry a long time ago. Pretty basic but allowed you to print out forms on A4 paper and glue them onto ply or whatever.
Or maybe your computer skills are better than mine(not difficult) and you have it under control.
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SUPeter, maybe you have looked but people have built kayaks and SUPs like this before. If you google foam strip kayak there are a few build threads.
As far as the forms you can do it on Shape3D if you have it or know someone with the paid version. There is a hollow board function. Mine expired sorry.
I used a free program called kayak foundry a long time ago. Pretty basic but allowed you to print out forms on A4 paper and glue them onto ply or whatever.
Or maybe your computer skills are better than mine(not difficult) and you have it under control.
Thanks Tarqiuin, I have seen this function back when I was thinking of building a hollow wood board. This "foam skin" design has a few idiosyncrasies which need accepting but I don't think it'll be any more difficult than similar builds.
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Well after mentioning kayak foundry I thought I would have a look and see if it still exists! Yes it does. Tried to download one of my old files and it opens up Navionics on my phone and says file to large to import?
I remember the problem with kayak foundry was .yak files and nothing would recognise it. Oh nightmares coming back!
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The 'Dowels' method looks like this:
I got a new board but knew that it had EPS foam ONLY between the tracks and the top deck so I added wooden dowels to transfer the load from Deck-to-Deck.
SUPeter did a similar thing with Carbon Rods. I would have preferred carbon but did not have an affordable source.
The idea is to create a table structure. 2 layers of 6 ounce Carbon over the tracks, then dowels through the board, then 2 more layers of 6 ounce carbon on the deck. What results is a structure that carries the load from the bottom of your back foot directly to the Mast Plate. The tracks at this point are just keeping the foil from falling off the board, but are not necessarily carrying the load.
I used 1/4" dowels on the outside of the tracks. Then 1/2" dowels in the center biased towards the front of the tracks because TRACKS ALWAYS FAIL UP FRONT from the compressive load created by the front wing cantilevered forward. I measured the distance from the tail using the template shown and drilled from the BOTTOM and from the TOP. Then had to meet in the middle. I cut the dowels ~ 1" too long. Fortunately the dowels loaded with Gorilla glue filled any internal voids and locked tightly into the BOTTOM and TOP decks.
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Top Deck:
There was a Single track on the top deck: In theory to attach straps. You can see the dowels that were routed flush with the deck. Then capped with 2 layers of 6 ounce carbon fiber. I then routed out the track.
Note: When I lay up the carbon fiber I do it on a separate sheet of plastic. Boeing makes aircraft grade Carbon : 70% Carbon Fiber to 30% Epoxy resin. I target 60% Carbon Fiber to 40% resin. I then weigh the Carbon, say 30 grams, and calculate the ideal ratio of resin (60:40 means 20 grams of resin so I'll mix 25 grams.
When you lay it on plastic, and weigh the ingredients, there is NO dripping of resin. What this means is that I don't need to fill my tracks. I can apply vacuum, let dry and route out the tracks without any infringement of Epoxy into the tracks.
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Fantastic explanation Beasho, thanks for taking the time
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Nice track reinforcement idea. I wonder if 3/4" Home Depot PVC board could work instead of a track for the top deck.
I have a board that can use this modification/ repair.
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The Dowel method looks killer, thanks for sharing.
PVC is heavy (density = 1.4 g/cc). I would use Paulonia wood instead (density = 0.26 g/cc and does not absorb water. [for reference xps has a density of 0.04 g/cc]
Ryan Burch rode a finless unglassed chunk of foam with a specific aspect ratio, which he called the Lord Board.
https://vimeo.com/15614139 (https://vimeo.com/15614139)
The board was fast, but fragile. Glassing the deck should keep it from snapping. I wonder if flexseal could be used on the rails. I repaired a catchsurf softboard with gorilla glue foam, then sprayed several layers of flexseal to give a pretty decent waterproof seal.
https://www.youtube.com/watch?v=K63S4KFk9Tw (https://www.youtube.com/watch?v=K63S4KFk9Tw)
I wonder how much cardboard surfboards weigh:
https://www.youtube.com/watch?v=BrIidL34rfw (https://www.youtube.com/watch?v=BrIidL34rfw)
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sflinux Thx
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Here is 1 board that inspired the XPS 'foamie' design for Foil boards.
The designer is hiding but he has had the board for 2 years and this is his current "go to" board for SUP foil surfing. I think he went:
1) Too heavy on the deck: It has 6 oz carbon on the entire top of the board
2) Painted too much on the bottom. The paint was thick and therefore weighty
3) Boxes do not Extend with high denisity or structure Deck-to-Deck. BUT the Boxes haven't failed. Meaning either the XPS holds, or the infrastructure built around the boxes was strong enough. I think the carbon dowels will cut the weight down significantly.
XPS Core. Carbon top deck. Carbon Rails (1 peeled off). 8" Carbon strip down the middle from box to nose of board. When it dings IT DOESN'T MATTER.
BUT most of the damage comes from loading into and out of the truck, or garage.
The board weighs ~ 17 lbs. 6' 6" x 30" wide ~ 125 liters.
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And the tail. What should I do with the tail?
I am thinking of keeping the rails VERTICAL.
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Regarding the tail, if you do the Kalama bevels, increasing towards the back, it makes the board pump great. Like a board with a kick tail, without having a kick tail.
It allows the tail to knife down into the water when pumping. No resistance.
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I like beveled rails or, in my case, flaring beveled rails especially towards the rear of board. This shape ejects water sideways, away from board during the hopping/slapping phase of the paddle up. Vertical sides may allow more water to eventually settle on deck when tail is submerged. Beveled sides also create a smaller hull surface and less surface drag on very bottom of hull when touching down at speed. I also agree that the less volume you have in the very rear, the easier it will be to sink it into the water just prior to hopping.
As far as vertical "posts", I use hollow carbon tubes,(arrow shafts), and not carbon rods(much heavier). Hollow tubes allow you to stuff resin impregnated carbon tow down inside leaving the flared out fibers to attach to boxes, hull laminate or deck laminate.
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Just a thought - there is a chance that constructing this into the board integrally could potentially be a lighter overall solution to getting boxes in the board:
https://foilmount.com/products/foilmount-3-0-carbon
I haven't quick conceived of the overall solution and it would probably require a few steps of layup since this isn't sealed boxes, they're open on the inside. But I'm generally thinking of a hybrid of the previously mentioned dowel system. We could drill a series of holes in the recessed area of the foilmount and screw the dowels into the backside. Then all of that could be glued into holes and a recess in the blank through to the deck area. Add some foam on top of the recessed areas and laminate the board as normal.
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Jondrums - Interesting concept and DEFINITELY Faster.
It says it weighs 1 lbs. I am hoping for 8 ounces for tracks and boxes BUT they are coming at the end of the week.
This thing could also be modular!!!!!! FAST And Flexible. Mmmmm
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What about square rails??? (edges)
Intuitively they seem bad BUT they could be:
1) Structurally stronger - A full box Structure
2) Better for standing on the deck. You get the full deck vs. rounded edges you're falling off
3) On the bottom - Does the water care IF this is a diplacement hull designed to go 6 or 8 mph??
- Prone to dings BUT with XPS I am willing to take that.
I am realizing that boards are OVERBUILT because they anticipate the user and 10,000 dings. If you are willing to take 5 or 8 dings then GO LIGHTER.
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I had a board built with straight rails looking for max float at min size. Corky is an understatement. Plus any swell or chop from the side was unbearable. I gave the board back to the builder since I couldn't ride it. Yes, of course I paid for it, it was my idea.
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Hard edges on the bottom, yes. Think McCoy.
Round or 45° bevel at least on the top unless you like bruises and painful tacos.
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I've used the carbon foilmounts a few times in experiments. they're damned nice, especially with the wizardhat hardware. I didn't expect them to be good, especially with boards that substantially reinforce to take the torque load of a foil. Surprise, surprise, they're pretty good. I did manage to delam a board with one, but that was an extreme example--a board that should never have a foil plate stuck on the bottom--a Wavestorm kids SUP board. It held together for a couple of weeks, which was about two weeks longer than I expected.
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I had a board built with straight rails looking for max float at min size. Corky is an understatement. Plus any swell or chop from the side was unbearable. I gave the board back to the builder since I couldn't ride it. Yes, of course I paid for it, it was my idea.
Pono: Can you comment on what type of board this was? SUP, Foil, Wing . . . .? Volume . . .?
Here is an example that Kane DeWilde has been riding. I am not sure who the kid holding the board is BUT the rails are DEAD VERTICAL. It is also super narrow ~ 18".
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I am thinking to make the tail like this FLAT tail (from the side) similar to this latest Kalama Skunk-Works Majine
https://youtu.be/vwbQdh8Rh8Y
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I once had a wise engineering manager say to all of our team, until you understand it better than the guy who invented it, you better copy it.
I was talking to a fellow shaper on the beach recently. I suggested he try a Kalama style board. Instead, we waxed on about all his better ideas, without ever trying one.
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I had a board built with straight rails looking for max float at min size. Corky is an understatement. Plus any swell or chop from the side was unbearable. I gave the board back to the builder since I couldn't ride it. Yes, of course I paid for it, it was my idea.
Pono: Can you comment on what type of board this was? SUP, Foil, Wing . . . .? Volume . . .?
Here is an example that Kane DeWilde has been riding. I am not sure who the kid holding the board is BUT the rails are DEAD VERTICAL. It is also super narrow ~ 18".
I would say he is not pumping the board as much as some. Because he weighs sweet FA and has a nice HA foil. So not worried about sinking the tail.
Again i dont foil.
But as foil and board design change there will always be a cross over point between foils and board shapes. And peoples skill?
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The whole wing foiling thing was amazing.
Got this wing thing its going to be awsome? No idiot.
Got this foil thing? No it wont work. Yes plenty of other sports are doing it.
Then like 10 years later you are where some sailing and foiling tech was 5 years ago.
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The mast placement relative to the KD Maui tail looks close, so close that it doesn't look like you would hit the tail while pumping. In a Progression Project interview with Kane, I seem to remember him saying that he likes simple structures in his boards as they are more predictable in a variety of conditions.
The GoFoil picture with the cutaway tail, the mast looks further up on the board, so much that it looks like the tail would hit the water when pumping.
How far do you put your mast from your tail?
Going back to the sub 10# goal of this project, is that to mainly minimize swing weight? If so, couldn't you use a lighter density foam outside the the standing area, as that part of the board is just there for volume, when on the water. I envision a board within a board, with the low density foam being unreinforced and replaceable with gorilla glue when damaged.
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Going back to the sub 10# goal of this project, is that to mainly minimize swing weight? If so, couldn't you use a lighter density foam outside the the standing area, as that part of the board is just there for volume, when on the water. I envision a board within a board, with the low density foam being unreinforced and replaceable with gorilla glue when damaged.
We are calling it the "Casette" within the board. Yes - Agreed 100% from my first post "Invest in the Foot area and the TRACKS. but Don't over index on the TRACK reinforcement."
Looks like this. Consider everything but the Cassette sacrificial. I am now looking at boards are realizing that they are designed for 1) Aesthetics and 2) 10,000 Dings. Or just call it INFINITE dings.
How many real dings do you get 5, maybe 10 over the period of 2 years. Yet the entire structure is designed for DING prevention EVERYWHERE.
I would estimate that boards add 2 - 5+ lbs from coatings to 1) Fill in the carbon corrugation 2) Wet out all the pin holes. 3) Give the board a nice GLASS clean finish
Current thinking: Beef UP the Cassette area. Then 1.4 oz glass Gorilla Glued to XPS. Add more infrastructure to RAILS ~ 4 oz S-Glass or Carbon for structural stiffness and ding prevention, Nose (Dings) and Tail (Dings).
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I feel like this has not been brought up in this discussion. As for the foil boxes a guy in Florida had it dialed in. No extra high density foam needed. Individual carbon wrap on the boxes that tie the top & bottom lam of the board together.
The guy in Florida also used 4 oz fiberglass with Innegra to make a really tough board. Composite Envision has 2 oz innegra listed on their website, but out of stock. one layer of 4 oz glass & 2 oz innegra would make a tough and light board. or just place the innegra at the nose, tail & rails for impact resistance. How about 2 oz fiberglass & 2 oz innegra - then carefully placed carbon reinforcements as needed.
I like the idea of using different densities of foam - Kings makes boards with 1 lb or 3/4 lb foam wrapped in 6oz & 4oz fiberglass - not ultralight but shows the light foam can work.
If I remember right didn't the Florida guy offer free ding repair for the first year?
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"The Guy In FL" is DW or Dwight. He's posting here and he's a genius who I have copied mercilessly and with great success for 7 years lol.
Ignore his ideas at your own peril. I experiment only after I try his way. Seldom (never?) do I make things better.
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I think the ultimate "cassette" concept would be a piece of prefabbed carbon/nomex honeycomb plate cut to the shape of the standing/footpad area - with a foilmount epoxied on the bottom of it. NSI adhesive strap mounts and leash attachment if needed.
alone it would be the the ultimate dockstarting platform. I expect it could be well under 4lbs with deckpad
Add to the underside closed cell foam "floatation" and hull shape.
Holy shit is is expensive, but you'd only need one of these and could iterate through lots of shape/size boards.
https://dragonplate.com/carbon-fiber-nomex-honeycomb-core-075-x-24-x-36
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I go peanut butter now. Not runny. I do squeegee one fill coat on first and then sand it all off/flat.
Squeegee the microballoons and then sand with 220 or even 320 between applications. When I think I've got the pinholes all full I do one more application and then I spray it with primer which shows any last pinholes. Fill em and go, or paint.
If you don't wanna primer it you can rub some resin on it with a gloved hand. When Peter says lean he means lean.
By the second application there's almost no material going on. I can do the whole board with like an ounce of material.
I'm digging my results.
Can you, or anyone, further clarify this step. My foil amigo is at:
9 lbs right now: 7' 6" Board x 21" @ 125 Liters
1 lbs EPS, Full 6 oz Carbon around the entire board, 12" Divinycell stringers under the BOX, 1/8" Divinycell Sandwich under his feet with 4 oz Fiberglass below and 6 oz Carbon on Top. Pretty bomber.
But he is paranoid about pinholes.
He has put on one "hot coat" with microballoons and sanded.
HOW DO YOU ISOLATE THE PINHOLES. What is the Primer Method??
He is down the final sand and seal layer.
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I end up doing 3 or so coats of the slurry. But it's all basically sanded off each time. You're just trying to fill all the pinholes which takes a few times. Then the last light spray of primer will show you if you got them all. If not, fill those and be done.
Adds zero weight. There is never truly a hot coat. Just fill coat, sand that and then slurry til the pinholes are gone. Why add 5-6 oz of resin? Because one thick coat is faster. Again we are back to production building vs custom for the lightest board and more time and money. This is partially why I build. We can do things in the garage you'd never want to pay someone to do.
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HOW DO YOU ISOLATE THE PINHOLES.
Who gives a crap. You cannot ever identify a leak by looking.
You must leak test with an ultrasonic tester. You add vacuum to the board via the gore-tex vent bung. You will find leaks that are NOT VISIBLE PINHOLES. Proving just how critical using the leak tester is.
Tip, pressure wash (after sanding) the board with a garden hose before leak testing to remove any dust that might plug a leak point.
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An ultrasonic leak detector is a critical tool for me for vacuum bagging as well as leak detection in boards. You have to find the big leaks another way, but the little ones scream.
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OK. I have an ultrasonic tester but never figured out how to use it well. I’m going to give it to Josh tomorrow.
What about using something like Saran Wrap in conjunction with a vacuum to see if it grabs any where when place on the board ??
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Here is my setup. It’s very important to throw away the headset it comes with. You need reliable clear sound. I’m using this cheap $30 Sony headset. It works ten times better than the junk $2 headset it ships with.
I drilled a hole through the goretex plug and fit a plastic tube. It fits tight. No sealant required.
One single invisible leak anywhere on the board will make the detector scream loud and possibly confuse you. When you find the leak, cover with masking tape and continue the search.
(https://live.staticflickr.com/65535/52652476410_05f105a867_b.jpg)
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Spraying on a clear sealer coat of Rustoleum spray paint(can) was my final option on my last DW board. Prior to that just the very runny microballoon coat during some drastically falling temps, all sanded off. No leaks so far.
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That's interesting DW, I swapped out the headset too, but mostly because the fit was crappy. I used some decent Sony headphones I had laying around--they look a lot like yours except the plastic is silver-colored. And I made a very similar adapter, though I turned mine out of brass and threaded it. I don't have exactly the right threads--I have a huge tap and die collection from years of working on cars and motorcycles, but none of them fit the plastic plug perfectly, so I just picked the closest one. I can get a turn and a half before it starts feeling funky. So I made a thick gasket face to do the sealing. Oddly enough I found a bolt in my collection of unsorted, unidentified fasteners that screwed in perfectly. I don't have a die that fits that either, so I taped the bolt to my vacuum pump in case I ever feel ambitious enough to make an adapter out of it.
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Here is my setup. It’s very important to throw away the headset it comes with. You need reliable clear sound. I’m using this cheap $30 Sony headset. It works ten times better than the junk $2 headset it ships with.
I drilled a hole through the goretex plug and fit a plastic tube. It fits tight. No sealant required.
One single invisible leak anywhere on the board will make the detector scream loud and possibly confuse you. When you find the leak, cover with masking tape and continue the search.
Now THIS is the sort of tips I need! Unfortunately these things are expensive :(.
I've resorted to doing the microballoon finish, sanding perfectly smooth with some pinholes no doubt. Seems like mixing microballoons gets air in the mix. Then just do a resin only hotcoat (pigmented like the one below it and sand that flat and polish if you like. Should seal up very well for minimal weight gain.
The only other thing is that if you have multiple layers of carbon/glass and you did a sealing microballoon coat of your board, you shouldn't have to worry. I'm neurotic now after my first board was laid up too dry and resulted in a major weight gain.
I have seen the aussie windsurf build video say he rubs on "porefill" that fills any pinholes, then it gets absorbed by the epoxy layer later. But I can't find any info on that stuff anywhere.
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I have used a hand vacuum test pump that is used on cars for bleeding brakes etc.. search "mityvac" harbor freight has them. It comes with hoses & fittings that allow you the connect to the air vent - you can draw a vacuum and look at the gauge. It won't help you find the leak - but it will show that the board is not leaking.
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Tracks going in:
1) Carved out the TRACK area in the XPS (removed 2.5 ounces)
2) Made a template for the TRACKS and where I wanted VERTICAL reinforcement to go. 4 Carbon Arrows DIRECTLY butted into PLASTIC Chinook Tracks
3) Cored CARBON arrows into Divinycell. NO need to drill the hollow rod would press through the Divinycell
4) Gorilla Glued in the 4 carbon Rods into the Divinycell cassette only at this point.
5) Cored out HOLES for 6 more carbon rods. These would be in-line with the first 4 rods, but just inside the Chinook Tracks. The last 2 were at the tail end of the Box
5) Lubed up the entire BOX and Rods and Vacuumed the whole Enchilada. I put light foam plugs in the holes to prevent Gorilla Glue migrating into cored holes. This step INCLUDED gluing in the first 4 Rods that were butting up against the Chinook Tracks.
6) Tested the Core Holes and re-cored. This was NOT easy. The plugs were more substantial than I thought and the BOXES under pressure migrated slightly. I couldn't just re-core easily with the rods. Took some coaxing and drill work, but the holes were at least in place and relatively VERTICAL because of the pre work I had done.
7) Glued in the remaining 6 carbon Rods. Total weight of rods @ 2.5 grams PER. Less than 25 grams, meaning UNDER 1 ounce. Weight of 6 rods shown @ 15.4 grams.
The board weighs << 8 lbs at this point AND is technically rideable although you would beat the heck out of the foam. I now just have to make it more durable.
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Deck pad adds a full pound. The lightest pads available add 3/4 lb to any board. Sucks, but that’s the way it goes. My guess is the 3M PSA contributes a lot to the weight.
Softer and thinner deck pads are lighter than firmer pads. Pad weights vary by color with all the US manufacturers. You need experience in picking pads to find the lightest.
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RSPRO Heexatraction pads, either the regular one (which fundamentally weighs nothing) or the cork ones which weigh a few ounces. I've tried roll cork glued down with high-strength 3M spray adhesive, but they don't last. I have the hexatraction cork on my Flying Dutchman board and they look the same as when I put them on after two years of flogging.
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Beasho, the board is looking killer.
The carbon rods looks bomber.
Do you think high density pour foam would be lighter than carbon rods?
https://www.youtube.com/watch?v=X496qvFC2bU (https://www.youtube.com/watch?v=X496qvFC2bU)
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Use 2mm Eva foam for the deck pad. 1/2 the weight of any “traction pad” material available anywhere. You will have to scuff the surface or put holes in it somewhere to get 100% traction. I ride mine untouched though because I’m lazy/haven’t figure out a slick way to add texture.
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I wonder how Mark Raaphorst's catamaran design (standamaran) would work as a foil sup.
With a catamaran you have stability and speed.
The platform gives you a direct connection to the foil.
Design:
https://www.youtube.com/watch?v=d39NOFm_hMM (https://www.youtube.com/watch?v=d39NOFm_hMM)
Test:
https://www.youtube.com/watch?v=e1TyAiIewhQ (https://www.youtube.com/watch?v=e1TyAiIewhQ)
UFO foil catamaran:
https://www.youtube.com/watch?v=59UyJESbhJA (https://www.youtube.com/watch?v=59UyJESbhJA)
cat dimensions:
https://www.multihull.de/technik/catdimension.pdf (https://www.multihull.de/technik/catdimension.pdf)
Peter Lynn designed one for a kite alternative to a buggy:
https://www.youtube.com/watch?v=N7gRKIBO4rA (https://www.youtube.com/watch?v=N7gRKIBO4rA)
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At the risk Mark being pissed at me, the Standamaran sucked. I know he had fun making it, and other people (the well-heeled Wailea Mafia) paid to have it made, but I paddled it (I forgot I weighed 260 back then), and watched the way the bow waves bounced off the hulls, made lovely interference patterns, and decided it was crap. Nothing in its short history changed my mind. I raced against a guy (Dr. Danger) who entered one in the BOP sprint and distance races and beat him in both races. And I'm fucking slow.
Catamarans tend to be very wide. Some folks think it's because that's stiffer in side-on wind, and it is (which makes the UFO design so user-friendly), but a bigger reason is that if the bow wave from one hull hits the other, you get a second swell forming just as you do from the stern of a regular hull, and that means wave drag. If they cross in the middle and hit both hulls you get a ton of drag and no benefit from the hulls being more than 10 to 1 ratio of length to width, you wind up having to power out of two (and sometimes three) bow to stern wave troughs. The standamaran was narrow--about the same width as an F16 (28"). It dragged a lot. No benefit for all that lovely and difficult work. You can see the interference pattern a bit in the video of Livio paddling the board, and to a lesser degree in the video of Mark paddling it.
It was wise of Mark to build it narrow, if he'd made a serious cat out of it no one could paddle it, and it would definitely trip going downwind in swells. Anyone who has raced catamaran sailboats (hobie, pringle, etc.) knows exactly what I mean by that.
Catamaran format doesn't automatically mean stability and speed. But I know Mark has one upside down hanging on the ceiling of his garage, and I bet he'd sell it...
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Deck pad adds a full pound. The lightest pads available add 3/4 lb to any board. Sucks, but that’s the way it goes. My guess is the 3M PSA contributes a lot to the weight.
1 lbs TOO MUCH at this point. My plan is for NO deck pad.
I will use wax, or the granules that you paint on for non-skid.
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Unbagging the "Sailfish"
Only for those who like SUP Foiling Christmas Unwrapping events:
https://youtu.be/Ma32EfB-nf8
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The board is ON Schedule
8 lbs 13.8 Ounces
It is FULLY Waterproof. Has 3X 6 ounces of Carbon under the feet and robust TRACK structure. I could surf this now but would beat up the foam.
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I am going to add ~ 12 ounces of ding protection and it is scheduled to be 9 pounds 11 ounces.
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another plus one for rspro cork deck. I now use it on 4 different boards. Its about $120/board, but so so light, very comfortable and great traction. Here's my recipe:
(https://cdn.shopify.com/s/files/1/0292/8297/products/RSProFrontGripIIcloselook_540x.jpg?v=1602603648)
(https://cdn.shopify.com/s/files/1/0292/8297/products/RSProsustainableperformanceTailGripmainimage_540x.jpg?v=1626708739)
(https://cdn.shopify.com/s/files/1/0292/8297/products/RSProFrontGripHexamainimage_540x.jpg?v=1626951183)
I use less than half of the hex pads, and you might be able to skip them if you don't have a wide stance. Here's what it looks like
https://www.instagram.com/p/Cah6j0CPxpN/?utm_source=ig_web_button_share_sheet
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The board is coming together on schedule.
Less than a pound left to go.
1) Bottom of the board. Tail section was 1.4 oz Gorilla Glued to XPS and Vacuumed
2) 4 oz S-Glass Epoxied on to Rails in Center section
3) Build schedule
Remaining laminations will largely be 1.4 oz Fiberglass on the Nose, top and bottom, and the Rails on the nose and Tail.
I may keep the laminations LIGHT and then see what dings, then reinforce. Although I will likely put a bit more build around the pointed nose and tail.
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Have you come up with a name for this board? Board looks great. Looking forward to a ride report.
"Nicht Zehn Pfund"
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Have you come up with a name for this board? Board looks great. Looking forward to a ride report.
"Nicht Zehn Pfund"
I am calling it the Sailfish. It is finished.
Final Weight: 9 lbs 12.4 ounces or 4.4 Kilograms
Is this the lightest downwind board in the World??
7' 9" x 21" x 6" @ 128 Liters.
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Initial test:
Some call it a Frankenstein. I prefer to think of it as a Fembot, the “Sailfish."
A quilt of Carbon, 4 layers thick at places, S- Glass and gossamer thin 1.4 oz E glass in the ends with Kevlar tips. All made from waterproof XPS foam which is heavier, more durable but also 100% waterproof. Half the board laminated with Epoxy and the other half with Gorilla glue.
The board was vacuum bagged for every step.
See the surface behind me. Paddled it around. Tried 5 flat water starts. Not there yet. Then the wind picked up to 8 mph. So I rigged the 8.0. Was on the 1300 with 450P tail. Ok this flies with very little wind.
Light wind 8.0 was fantastic. Wind got a little more consistent so I took it in the ocean, big swell 11 feet at 17 seconds outside the harbar and wind was picking up way overpowered on 8.0 now gusting over 20+, tried gliding on big swell, came back upwind and rigged down to 5.5.
Simply the best wing board you could possibly have (Note I did NOT make this as a wing board but it worked great and I am not trying to jump like Titouan Galea nor beat Johnny Heineken in a race). Why go small when you can have float to survive the wind dying in a board that weighs as little as a 4 footer.
Ohh and when it touches down it doesn’t even feel the surface. Gentle kisses.
Ohhh and it will take off on Nothing!!!!!
PS: Someone noticed 'No need for a handle when the rig is light enough to just grab by the mast at the base of the board. Meaning so little nose weight it doesn't matter if you aren't centered with your grip. . . . . More to come.
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Congrats Beasho, looks like a sweet ride.
Thx for sharing so many details, will come handy for sure.
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That came out awesome. I'd call it the stealth bomber.
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Nice board. After some sea trials could you share some feedback? I'm admiring the plan and would like to fear any changes you might consider to either design or build after a few hours. It looks really good man.
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Quick Update: 32 Sessions later.
I have been out on this board for 32 Total Sessions:
- 19 Sessions SUP Foil
- 7 Sessions SUP Foil
- 6 Session Wing Foil
I have only had 1 Mellow day on this board: Meaning Glassy 2 - 3 foot day. Every other session has been a mixed bag of Big to Imperfect to HUGE. Buoys have been regularly going from 5 to 20 feet. 1 of the downwind sessions in the bay was blowing 35 mph gusting to 45 mph. Another session was blowing 40 gusting to 60 mph. Totally nuts. The Epic Kayak guys said it was the windiest they had ever seen it from Coyote to 3rd Avenue in 15 years of their experience.
So the board has been taking a beating. There has been wear on the rails. I have made the following ADDITIVE modifications:
1st - Where my legs, calves, would sit when paddling with my feet on the nose. I also felt I was compressing the foam when I would get on the board. So I added Carbon further up-front on the rails and extended a triangle patch on either side.
2nd - I added front footstrap plates
3rd - After 30 sessions I notice cracked rails on the left side only. This was a combination of 6 oz Carbon and 4 oz S-Glass. I sanded OFF the rail, added 2" S-Glass and then 1" Kevlar tape.
Observations: I have had sessions where I was out in horrific wind and chop and fell 30+ times. One time I was halfway through and lost count and never caught a wave I assume I fell 50 times. 30 Sessions * 20+ falls per session is 600 times climbing on the board. That wears the rail. BUT I usually climbed on the left side. So only the left rail was cracked. I added the Kevlar, with Gorilla glue for wear protection.
The board with all those additions is 5 oz heavier. Just the weight of the materials. NO WATER weight added.
No other delaminations. There are 2 minor dings that were in the 1.4 oz glass from Day 2. I never patched them. No propagation of delaminations around the dings. In fact the only place that cracked or delamed, on the rails, were the EPOXY matrix. The Gorilla Glue laminations are all holding perfectly. The Boxes show NO signs of any wear.
There is evidence that Gorilla Glue is superior to epoxy when it comes to laminating FIBER to FOAM.
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Current Weight: 10 lbs 1.3 oz
This board in a surf bag weighs 13 lbs which is still lighter than virtually all boards @ 128 liters.
Meaning that most boards have the board bag built ON TO THE BOARD permanently for ding prevention.
But I get to go to the beach and take off the 3 lbs of Unnecessary Bag weight.
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I dunno what impresses me more, how well such a minimalistic board is taking the wear or how many days in the water you get :)
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are you finding that you need/want the front footstrap? I have been assuming that it wouldn't be needed on a downwind style board. I mostly use mine on my "shortboard" for force pumping the board into a wave. Seems like the takeoff action on a board like this is more about getting up to speed rather than pumping the board out of the water
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I have been using the board in waves as big as 7 to 8 foot faces. Granted they are mushy, and soft but the takeoffs are pretty hot. Especially when using an Axis 1300 and 450 P tail. Those are the only foils I have been getting used to.
When my front foot is locked, forward in the strap, I have 100% confidence in the takeoff. Also a strap helps to man-handle the board better with the big wings.
Add to this, surf amigo Josh, added a front strap to his Kalama. He is convinced it helps him lift the front foot to better takeoff in Flat water. I too would claim this benefit but am not as experienced as he is with the flat water takeoff.
So the front strap:
1) Adds confidence on bigger wave takeoffs
2) Helps better control the board
3) Allows for upward pull on the board when going into Hop / Bounce mode for takeoff
My front strap has 13" between the bases. This gives me ~ 8" of lateral play. Meaning I can push my foot forward for takeoff and slide it back several inches to optimize pump mode.
Here was a video from last weekend. Josh taking off first, Kalama 7' 10" with Axis 1300. Then Kyle, also on Axis 1300, homemade board 7' 6" x 120 liters @ 10.25 lbs. Kyle's board was made from the same template as my board. His has an EPS core, lighter, but then several layers more hot coat and lamination for waterproofing.
This session was a "game changer" because the prone guys were all clumped on the inside relying on white water to take off. Hence the "Unbelievable" comment from the peanut gallery of proners. Many are resistant to using the paddle for takeoff. They had first hand views of the benefits of longer, thinner boards. In clean conditions you just takeoff wherever you want.
https://www.youtube.com/watch?v=omr5ru758gA
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are you finding that you need/want the front footstrap? I have been assuming that it wouldn't be needed on a downwind style board. I mostly use mine on my "shortboard" for force pumping the board into a wave. Seems like the takeoff action on a board like this is more about getting up to speed rather than pumping the board out of the water
Jon - I just spoke to Josh. He said YOU taught him the trick of using the Front Foot Strap to lift the board up to take off sooner when you were both in Southern California. He is using the exact same technique with his Kalama. It all comes full circle.
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wow, watching Josh and Kyle taking off on nothing like that - I can see the game has changed again. glad to hear the feedback that the footstrap is still useful, I'm totally sold on front footstrap but I don't have a flatwater/downwind rig. Yet!
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Current Weight: 10 lbs 1.3 oz
This board in a surf bag weighs 13 lbs which is still lighter than virtually all boards @ 128 liters.
Meaning that most boards have the board bag built ON TO THE BOARD permanently for ding prevention.
But I get to go to the beach and take off the 3 lbs of Unnecessary Bag weight.
Denton I am giving you more credit, the production boards close to that literage weigh 15-18+, so we are talking about a huge weight reduction, and reduction in materials. Add to this most of the weight is under foot so the swing weight savings in the nose are extra huge. I have found less nose weight on a 7' board to be night and day difference, I can only imagine how much more noticeable it is on an 8 foot board.
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Next Board is being built.
6' 9" x 26" x 5" @ 119 liters. Target weight 9 lbs 12 oz.
XPS Core: Top 1" is 1.8 lbs per cubic foot. The pink 2" x 2 slabs is Home Depot Foamular @ 1.5 lbs per cubic foot.
My Sailfish has 40 sessions now. There are some dents on the deck that are parrallel to eachother (?). Meaning square stance, but I never stand square - KNEE dents.
Having fallen of the board at least 20+ times per session I estimate 800 remounts, kneeling and standing on the board. That's a lot of knees.
My rail on the left side is also showing constant wear. I suspect this was from climbing on Over-and-Over. The edge was NOT rounded enough. I liked the square edge for control, but BAD, BAD, BAD for wear resistance. Going to go for 1" Diameter on this new board.
Also - I am going to use 2.2 oz Kevlar INSTEAD of 1.4 oz Glass on the bulk of the Nose and Tail. Much better wear resistance at a similar weight.
PS: I hot wired the rails with a $38 Amazon hot-wire kit. Worked great for rails. I needed some help from our local 'shape-shack' to hot wire the nose rocker with a 30" wide wire and template.
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My latest lamination was my best yet.
I added 2 patches:
1 along the centerline for stiffness under the "Cassette" area of the board. This would be between the front and rear feet.
2 Rail to Rail to prevent any roll, adding lateral stiffness
The Tracks will therefore have 2X 5.8 oz Carbon above them. There are 10X carbon rods, 6 extending from Deck to Deck, and 4 running from the top deck to the bottom of the tracks. Total weight of dowels 25 grams.
Each of patches weighed 38 grams (coincidentally). I mixed up 2 batches of 50 grams of Epoxy, and 1 batch of 20 grams.
I marked up where the laminations would go with a sharpy, then sanded the surface of the foam with 220 grit sandpaper.
I then:
1) Painted the surface of the XPS with the 20 grams of Epoxy. I used ~ half the batch to wet the foam with a squeegee. This ensured I would NOT have any dry spots under the carbon.
2) I wet out the 8" x 38" center patch on a table on WAX PAPER. I used ~ 40 grams from the 1st 50 gram batch. Wetting out on a hard surface permits better saturation through the fiber using a squeegee. Then the whole piece of carbon, with the Wax paper is placed on top of the board. At this point you can do a final alignment of the patch, then press the top of the wax paper to thoroughly compress the resin into the fiber. Finally gently peel back the wax paper at a 180 degree angle.
3) I wet out the 14" x 21" patch again on wax paper on a table with ~ 40 grams of resin. Applied the patch to the board, centered and removed the wax paper.
I always add a touch more resin to the edges at the end, and look for any potential dry spots. Bag and vacuum.
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Results look like this:
Estimated additional 4.6 oz. Actual add 5.4 oz.
This difference might have been from thirsty foam, especially around divinycell which readily sucks up resin.
Super clean and crispy. No dry spots.
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Here is the current build schedule.
When accurately weighing the fiber, and resin then vacuum bagging with
1) Peel Ply
2) Perforated Release
3) Breather layer
4) Full 20 in HG++ (You can only do this with XPS foam rated at 15 psi or higher)
The resulting weight of each additional lamination is nearly exact to what you would predict with a 60% Fiber to 40% Resin ratio. Meaning there is no guessing what the final board will weigh. It turns out to be just a math exercise.
Modify message
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Next Board is being built.
6' 9" x 26" x 5" @ 119 liters. Target weight 9 lbs 12 oz.
XPS Core: Top 1" is 1.8 lbs per cubic foot. The pink 2" x 2 slabs is Home Depot Foamular @ 1.5 lbs per cubic foot.
My Sailfish has 40 sessions now. There are some dents on the deck that are parrallel to eachother (?). Meaning square stance, but I never stand square - KNEE dents.
Having fallen of the board at least 20+ times per session I estimate 800 remounts, kneeling and standing on the board. That's a lot of knees.
My rail on the left side is also showing constant wear. I suspect this was from climbing on Over-and-Over. The edge was NOT rounded enough. I liked the square edge for control, but BAD, BAD, BAD for wear resistance. Going to go for 1" Diameter on this new board.
Also - I am going to use 2.2 oz Kevlar INSTEAD of 1.4 oz Glass on the bulk of the Nose and Tail. Much better wear resistance at a similar weight.
PS: I hot wired the rails with a $38 Amazon hot-wire kit. Worked great for rails. I needed some help from our local 'shape-shack' to hot wire the nose rocker with a 30" wide wire and template.
On the second pic, what are you using as a guide for the hotwire?.
Is it a braided steel wire or solid metal rod...?
Thx!.
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On the second pic, what are you using as a guide for the hotwire?.
Is it a braided steel wire or solid metal rod...?
Thx!.
A Piece of solid piano wire ~ 3/32" thick that I soldered metal tabs onto. Then I contoured the angle and TAPED in place. The tape didn't want to stick very well, so I tripled it up.
I used an aluminum ruler for the other side of the guide, on the flat edge of the board.
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Homemade Sailfish vs Barracuda. Taking off on the same wave.
Josh on the Barracuda (7' 10" x 19" x 115 liters @ 13.5 lbs), Kyle on the Sailfish 7' 9" x 21" x 128 liters @ 10.1 lbs):
https://www.youtube.com/watch?v=dN4f3WCNZ9o
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What foils are they on and what are their body weights?
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What foils are they on and what are their body weights?
- Josh - Barracuda - Axis 1300 - Tail 375P - Weight 185
- Kyle - Sailfish - Axis 1300 - Tail 450P - Weight 175
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Nice. That's a good comparison.
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sorry to geek out one step too far, but I guess that's why we're all here anyway, right?
What fuse lengths are they on?