so keep pushing the boundries
better than sitting around a table swimming against the tide
cheers huie
[/quote
Well that about sums it up, and I couldn’t say it any better.
Those vids are hard to watch. What a panel of ''experts''. They've ''discovered'' volume lol.
Rawson just sits there looking pained most of the time. I think marketing guys make him uncomfortable.
huie friggen nailed it.
Just throwing something out to think about. I’ve been seeing some builders getting on the Modern fabrics trend. But what I’m seeing looks like Tulle fabric http://www.bbcrafts.com/tulle-fabric+666630.html?gdftrk=gdfV2203_a_7c244_a_7c7355_a_7c12513&gclid=CJ-o08PstrMCFaN_Qgod_iwA0g, and mosquito netting http://www.suntekstore.com/goods.php?id=14001985&utm_source=thefind&utm_campaign=5.
Sure, it is an inexpensive way to get additional reinforcement, and it is silly inexpensive. Just my thought, that when a builder comes with something “high tech” it could just be lipstick.
Mark, i test it both. Tulle i found was 20g/m² nylon grid (same thing as gridlox) and mosquito grid was 45g/m² pet. I test linen, flax and cerex too and many other plastic veil (PE/PP/PET/kevlar and carbon from 8g/m² to 100g/m²). I made test panel with only the fiber, fiber between glassfiber, fiber over or under glass. Then i did dynamic 4 points flex test to measure stiffness, break force, stretch to break, calculate energy to break.
I found that all reinforcement with a lower stiffness and a higher stretch to break than resin only acts as bulker: they increase thickness of panel wich increase stiffness = better buckling resistance. No matter wich one you use, they don’t increase mechanical properties of resin. At same weight better results for stiffness with bulker between fiberglass. At same weight no real advantage over al glass under 1mm thickness. I have same results with only thin coat of resin between fiber . Only “real” fiber like kevlar and carbon increase drastically some properties. For some properties resin play a bigger role than i think.
Because surfboards are sandwich i play now with panels with all kind of core, skin and stringers. What i find right now is something i read here and in many mechanical thesis: surfboards snap because of local buckling where shear stress break core and/or bond between core and skin. If you want a stronger surfboard you have to increase buckling resistance of skin and/or increase shear strengh of foam. Not really easy to do effectively without stiffening to much board or increase weight or cost…
Sorry for my frenglish.
nylon sports net is good to use under vacum as it is light and a good resin transporter through the laminate
it suits the builds i do with wood skins nuetral rails it does absorb impact’’ i dont see it as a bulker? and stiffing the rails in my builds kills performance.
josh dowling put me on to tulle yrs ago and i like it under skins but i think the net is a better proposition
** cheers huie**
Interesting how business works. A marketer will take something simple like Tulle fabric from a clothing store, rename it something like “Gridlock” and resell it. Same with Cerex brand “N-Fusion”. Add a mark-up to the cost, and call it “Skinz”. But I guess that is how it works.
Lemat, You find that adding some of these cloths does nothing more than adding a hotcoat between layers of fiberglass. That would be the threshold then. Does an added fabric do more than just having a thicker laminate, by not pulling off the epoxy when glassing?
Exactly! To strengthen the skin/ core bond, you will increase stiffness. So the stringer becomes detrimental, or at the least, redundant. If you are working the skin to take the stresses better, remove the stringer.
Huie,
If you are using the sports netting as a resin transporter, would that be for resin infusion, rather than a standard hand laminate? What sport netting are you using?
Another thought is that board thickness is also related to stiffness. The foil and shape, as well as the skin, as well as the core all are involved in the flex pattern.
Hy huie, for long time i think that nylon grid (an others similar plastic) in laminate absorb impact but in fact mechanics show that it can’t absorb impact more than resin because nylon have similar strengh than resin and is advantage of stretch is restricted by resin stretch, lower for “classic” epoxy surf laminate resin. All in all it don’t absorb more impact than the same thickness of resin only. But those grid and veils are very effective to keep thickness of resin (bulker effect) mainly if you work under vacuum. It’s important for good gluing of skin too.
sorry for my frenglish
I highlighted the bond aspect becasue in my limited testing I definitely found that cerex/skinz/nylon veil increased the bond between glass and foam. It was much harder to peel the glass off the foam when it had skinz as a first layer than it was to peel off just glass or innegra and glass off the foam. The board I made with .7oz skinz/2oz innegra/4 oz glass on the deck has dented up pretty much like a 4oz/4oz glass job which left me disappointed. But I’m hoping the increased bond will delay delamination. Deck denting which led to delam was always the end of my PUPE boards.
lemat
** while lab tests may prove you right. the surf test tell me it holds the lamiate together’’ and resin fracture is not as bad as just using e glass.
**
remember we are talking about skins to suit special core and no matter what fibre you use? there is non better than wood?
and infused wood with nylon well it just gets better eh’’
**try a peel test with the sports net sticks like shit to a blanket **
never used it hand lam? only vac and i use a more flexible epoxy than the surf ones
**i said it over and over infused wood with nylon is my journy . **
so not realy bothered with much else
but hey that dont mean its the only way just suits me thats all
**cheers huie
**
Huie, you should post more photos of your boards. Eye candy.
flexible resins are accesible from adhesive technologies… great info huie.
If I remember correctly at one point Bert Berger said he was using three different kinds of resins in his builds.
Resin Research sells different versions of his resins that have more and less flex than the RR 2000 that gets sold through the surf outlets.
for your consideration.
- **Brown sample**, Cramer brand nylon 6,6 woven 4 oz, under Cordura brand Nylon 6,6 woven, under Cerex N-Fusion 1.2 oz.
- **Red Sample** , Cordura 7.4 oz ballistic weave with a polyurethane coating, under Cerex N-Fusion 1.2 oz.
- **Clear Sample**, 2 layers of 4 oz. S cloth.
Results are close to equal for both Cordura samples. The red Ballistic sample was slightly stiffer than the brown sample. Both outperformed the double layer of S- Cloth.
So I go to the Cerex site and fiil out the free sample list and like an hour later the sales rep calls me. He wanted to know what I want a sample for . So I say to make surfboards, man that sure got him excited!! said he just got back from the west coast and everyone wants some.Also said somthing about making nylon stringers, all I asked for was a sample and im getting 30 yds to play with, real nice guy give him a call, all for testting this stuff like everysurfer is doing
Is there a reason why I cant see the pictures in this thread?
Because all my images disappeared from my account. When I tried to add more pictures, I got an error message. I p.m.ed Mike Palar about it, but so far no reply.
one year on and where are we?
cheers huie
The site has been having problems for several months now. Paler is aware of it, and has been working on fixes / changes. The classifieds are working again finally, but search function is still down, and pictures have been an issue for a lot of posters.
The workaround on pictures is to use a third party picture hosting site like flickr, photobucket, picasa, etc. Then use the picture’s url with the picture icon / popup window when posting.