interested to try some as deck patches with the lightest blank I can get.....
Just remember that sandwich thickness is key to sandwich strength (i.e. separation of the layers). I think the veneers work because they are 0.4-0.6mm thick, rather than their inherent strength/flexibility. Of course I’m often wrong…
Ineggra
heres a cple pics so far it is the best polyprpolene i have used
but ferel dave has summed it up best not the best for production’’ hard to cut a clean edge.
so fwiw heres an inlay this board is 4 1/2 lb sanded so the innegra 2oz with a 4oz plan weave over has not given me any weight prbs
the deck feels mighty tough so know i will give it to the deck destroyers see what goes?
**[img_assist|nid=1046428|title=innegra inlay|desc=|link=none|align=left|width=640|height=480][img_assist|nid=1046430|title=innegra inlay|desc=|link=none|align=left|width=640|height=480]
**
mmm. nice Huie. i think i might get you down here one day to do some finish coat lessons to my production staff! i too use innegra under 4oz. only way i would use it on a bottom is vacuum bagged…
Huie I am extremely impressed!
Great work on your part.
Your the man and much respect for the man down under!
Surfding
Huie what foam did you use on that board ?,I did a test board on the weekend with 4 ozs innegra on the deck with 4ozs glass bottom and a 4 ozs glass over the innegra on the deck ,I used xps foam on this one ,6' 2 X 17,7/8 X 1,7/8 .finnished board with glass on fins came in at 2.1 kgs ,(all the glassing was done in one hit ,)
[URL=http://img36.imageshack.us/i/dcp03510.jpg/][IMG]http://img36.imageshack.us/img36/8789/dcp03510.jpg[/IMG][/URL]
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hey leigh your boards look allright eh.
yea the board in pic is 5’ 10’’ x 18’’ x 21/8’’
** one big difference c d d blank
**
c d d is the best kept secrete on the planet.
CORE is critical.
a rail lap good fun eh dave’'[img_assist|nid=1046610|title=innegra|desc=|link=none|align=left|width=480|height=640]
I wonder how new this material really is or in what way it is new. Innegra S is made of polypropylene, according to http://en.wikipedia.org/wiki/Polyolefin “Polypropylene is another common polyolefin which is made from the olefin propylene.” On http://oneoceankayaks.com/Abrasion.htm#synanch they tested olefin cloths in september 2000 according to wayback machine, including a polypropylene cloth. So I wonder what is the difference between Innegra S and other polyolefin and polypropylene cloths. That said, it’s great if this new product makes this types of cloth easier to obtain and get acceptance in surfboard construction.
look at the pics i have used the other polypropylene& to my knowledge this is the first plain weave
for production it still needs some time to settle in &get worked out
to build myself a board &go surf i would use it in a heart beat’’
2 oz is all you need as 4 oz comes out to stiff
impact impact’’
Hi Trevor
CDD Mate are you ever going to tell people how we make these blanks, maybe wait a few months so I can get production running smooth again after the move to Indo. Cant wait to try this cloth with you, should work well with the CDD blanks. Catch you on Skype Peter
hey peter
heres one i done with one of our old blanks never thought we could glass one up this light
been geting some good feed back on the traveller
** ps dont make these guys jellous with all that indo talk haaaa’'[img_assist|nid=1046846|title=empire in ennegra|desc=|link=none|align=left|width=480|height=640]
**
You know i’m jellous!!!
Hi Peter, wish you all the best and smooth sailing.
I used Innegra from Innegrity as part of a test for the company and distributor for the product.
In plain langauge, Innegra is a "skin thickener" to make stiffer composite panels with resilient properties. We had several execs from the company check out a board in production and had quite a discussion for the intentions and potential for this material.
Their intentional target market seemed to be Formula 1 race cars as their high end effort and high-performance boat hulls as an example worldwide market. Many,many uses for this product were realized as exampled below. The material lays up about 40 percent lighter than a normal E-glass lay up of similar resin/fabric ratio.
Basically, before Innegra-type materials were available, when a composite part was designed, (like the GP Formula 1 body panels) the schedule was very specific (ie. "apply 15 layers 8 ounce biaxial carbon graphite along the lengthwise axis, 10 layers at 45 degrees" etc.) Several things were happening. To build up a stiff enough skin, MANY LAYERS of graphite fabric would be used. Engineers/Designers love graphite as it has almost equal tensile strength as compressive where fiberglass has about the same tensile strength but almost NO compressive strength. The problem is internal layers do not do nearly as much work as the outer layers do, so piling together many layers of graphite to get a structure stiff enough was kind of a waste. Also, the energy absorption properties of thick graphite panels is thorough, read that as "explosive" in the case of Formula 1 collisions/impacts, where the cars will literally disintegrate upon impact, shatter may be a good term.
To save money, Innegra can be used to "bulk up" panels and make them thicker. I was told that Innegra costs about 40 percent of the cost of fiberglass (not sure if I should say that but I never signed a non-disclosure.) The added bonus was the "fluffing" property that Innegra has. We found it "sponges" up resin and gets at least twice as thick as an equivalent layer of fiberglass (6 ounce for example) BUT you can squeeze out the resin pretty dry and the Innegra would still fluff up AND it would have virtually NO pin air. Lastly, Innegra appears to have good ballistic properties, being much more robust than the graphite inner/outer skin, so on impacts the integrity of the structure is better maintained.
Cheaper, lighter, bulkier, all good things when used with the right intentions. The company was interested in seeing various hand lay ups that we were doing. I told them how nice it would be to have a sandwich skin that could form over compound curves without induced stress- I mentioned my ideas of a "liquid sandwich skin" and this piqued their interest. I was also told about other R&D, surfboards being built in Australia, and some work on the East Coast. Innegra would be a nice material when used in combination with the right core and possibly other fabrics or skins/shells.
One thing that we discussed was how to make a thicker, yet lighter skin and why. Skin stiffness is a cubic factor, so if a skin is 0.05" thick and you double it to 0.10" the skin will be "2, cubed" stiffer or EIGHT TIMES stiffer against local flex.
Thus thicker is desirable for local panel stiffness (read that as "pressure ding resistance") but that always came at a weight penalty, like a deck glassed with 3 layers of 6 ounce. Now there is an option that would only weigh as much as a layer of 6 and 4, but basically not dent. One good attempt at stiffening skin was to introduce a plethora of sandwich skin materials, like wood, foam sheet, etc. Innegra, when combined with other fabrics is good in that the global panel stiffness (read that as the board bending and snapping) is NOT affected. The higher modulus fibers will do most of the work (eg. Layup schedule of 1.5 oz E-glass, 6 oz Innegra, and 1.5 oz E-glass will act similarly to a board with a single 4 oz. but will resist denting and yet stay lively (assuming decently matched moduli, of course.)) This goes against the effects (or side effects) of vacuum bagging. Less resin is used which is good, but the skin thickness is smashed very thin which, if not used with any other stiffener, is bad. We agreed that vacuum bagging is mainly intended to make laminations conform to a shape, but a hand lay up allows for the sponging/fluffing effect that Innegra exploited. Innegra does compress when subjected to vacuum compression.
I could go on about the performance and some of the negative attributes of this and other fabrics but I think I wrote enough...
George
Mike Daniel, remember when I found CAP (chemically activated polyester) cloth through Noah Industries in the early 80’s, the cloth looked like crap, but the boards were bullet proof.
Larry Pope loaded a box of Clark sheet foam into my Chevy Van and right onto my twin fin, I left he foam in the truck for week, it weighed about 200lbs., When I got some help to remove it, my one fin was flattened onto the bottom of the board. but it did not shatter anywhere around the base.
I had to die grinder around the fin to get it off the board, the drawback was hitting any fiber during sanding, the resin sanded away and the cloth stayed behind, too the iron to it and melted off the fur
Hey Jim, sure I remember the CAP cloth. I also recall you cursing a bit when you found your twin fin under the box of foam. And when you tried to sand the CAP cloth. Kurt Wilson also used some unusual words when he tried to sand. More Magnolia Street madness...
That was before the fall of 81 judging by the boards I remember built.
I’ve never used it or even touched it, but by looking at its properties it doesn’t seem novel. Though I would say that it definitely could be useful, if applied correctly. The material is polypropylene and their patents don’t suggest that they changed the chemical structure:
It seems that they have just developed a unique application of an old product.
**WHY IT WORKS:
**(in supplement to PlusOneShaper 's awesome explanation( #55 comment), not in contradiction!)
Basically, if you are using a highly cross-linked polymer (a thermoset, more cross-links=more brittle) such as Silmar polyester, you can increase the strength of the composite by mixing in tough materials. Thermoplastic(not cross-linked=ductility) fibers such as polypropylene (innegra), can help add toughness to the composite. Toughness is a term that refers to how much energy it takes to break a material. Brittle materials are not tough, so when a crack forms it instantly propogates (you see this in glass windows, or spider web fractures in around a ding). Polyester resin, e-glass and carbon fibers are brittle materials. When a micro-crack (non-visible crack) forms in a brittle material it quickly grows into something visible. If you add some tough fibers, like Innegra, to your composite, when a micro-crack forms it tries to propogate, but it quickly runs into an Innegra fiber which absorbs all the energy and redistributes the stress. Therefore, the micro-cracks never become visible cracks. Also, the composite is stronger because stress concentrations from micro-cracks never form. E-glass carries most of the load and the Innegra prevents cracks from growing. You think that your composite is now crack-proof, but really you just can’t see them, which of course is a good thing. However, I am willing to bet, that with non-visible micro-cracks, you get a slow ingression of water which will degrade the performance of your board over time (probably why polyester boards are lively for a short time)
So, is there something special about Innegra? Yes, they made this simple concept available to shapers. However, the same thing can be accomplished with polyester fibers (used in print sreens), polyethylene fibers(most commonly “UHMWPE”) or many other thermoplastic fibers that are in current production. You just need to find someone with a loom to weave them with your e-glass. I’ve used them, it works.
Of course the real solution is to find a resin that is not brittle, that can stretch at least 3% (6% and you’re gold). Then you won’t even get micro-cracks. If somebody knows of such resin, let me know.
Benjamin
Could you explain what this means? Thanks.