On Hexcel’s (and JPS’s) website - http://www.hexcel.com/user_area/content_media/raw/DSF_6220ht.pdf - http://jpsglass.net/wp-content/uploads/2015/07/6220.pdf - they list a 3.0 oz/yd (104gsm) S-glass with direct sizing, which in theory and according to their data, has an even higher tensile strength than regular s-glass…but it doesn’t seem to actually exist.
Anyone know where to find this specific unicorn?
call contact number and I am sure they would be happy to sell you a roll or maybe a 10 yard sample…
They use to have a factory in Sequin Texas. If you are from Texas go and get the end of the roll for pennies on the $$
This is absolutely crazy, but I’m going to be in Seguin next week. I called Hexcel just now to see if they had any in stock. She doubts it and doesnt know if they can let any out the back door if I were to stop by. Might be better to try JPS in Anderson. There is a company in SC that sells end pieces of rolls that might have it, Thayer Craft. They are next door to Anderson.
all the best
that’s 60x58 thread count… probably contributes to the tensile strength. Not much fun to laminate, I bet.
Maybe, Keith, but I’m thinking that being direct sized, it will drape and wet out pretty good.
All the best
Some good info! I will follow up with those leads and report back. Thanks. If any blows away in the wind feel free to let me know. Particularly interested in it’s drapeability.
Hexcelc and JPS report this stuff is made to order and min order is hundreds of yards. If I can find a few offcuts or samples I’ll report back.
For the discerning builder using modern foam I think the industry is ready for something slightly lighter than the common “4oz s-glass” which is usually 3.7oz s-slass.
This is almost 3 times as much thread per inch.
FYI… Just finished a roll of something that had a high thread count and tight weave. I bought it years ago on eBay thinking it was a score. It was a major pain to hand laminate.
I had to roll up the glass from rail to center to expose as much of the board as possible, then lay resin down on the board either by brush or squeegee, then roll out the glass over the wet board then smooth out the glass. I could only roll up half the board, so one side would get wet then the other. Worked OK for clear or solids. Didn’t breath well, so bubbles or pin holes where there wasn’t enough resin below were also a pain.
By comparison a normal surfboard glass is so much easier to work with, even if I do 3 layers at once. If you try this stuff get a small batch and see how you like it.
Good info
Thanks sharkcountry
Good points. My idea is that it being a 4 harness satin weave and light weight overall it might work with a slow curing, lowish viscosity resin, and lots of patients. But then again it will probably be a pain in the ass but I like to experiment.
Surfboard skin are thin membrane that experiment tensil and compression, tensil strength of Eglass is far higher than needed, no advantage for sglass there, and many other things to do far effective for compression. So eventually for penetration (dings) …
If you don’t mind the extra hassles of doing the lam, it is a stronger glass. I’d try to do it with a wet out table then roll it over the board once it is wet out. Watch some of the videos of guys making sailboards and see how they use the wet out table. I’d wet out the glass then paint a bit of resin on the board if it’s EPS. Many times the glass would end up slight cloudy, not clear. If you want clear lams, you may end up with issues. I used it for making fin panels and it really shows how it is less clear.
S glass has greater elongation to break than E and some data reports nearly 50% greater (1.5x) compression strength. A data table from AGY literature reports a 20% higher Young’s modulous as well. Not huge improvements but potentially significant. I am pushing strength to weight limits with sub 5 pound shortboards using 1.5# eps, and s glass seems produce “stronger” boards that dent and spider fracture less, but it’s only by a little bit. Could be my imagination or other variables though. With 1.5# eps core and only 2 layers of 3.7oz glass I need all the extra strength I can get…even if it’s imaginary :-).
“generic” data from norme that i use for calcul are not so impressive. compression data for fibrous reinforcement is a no go because it’s shape (length/thickness ratio) of parts that dictate how much buckling shear stress take resin to keep this shape, when resin go parts go. Lighter is foam stiffer need to be skin. depend your critère but increase thickness is in general more effective than increase material stiffness to stiffen a composit skin, that’s sandwich purpose.
Do deck channels or other corrugation type design function similar to an increase in skin thickness? I picture deck channels as taking a 2D skin and giving it a 3rd dimension to help transfer or resist/distribute stress.
Also what do you think of a stringer? Is it just a old throwback that adds weight vs perhaps no stringer and another layer or two of cloth?
I’m thinking 1# eps, stringerless, deck channels, 3x layers on deck (2 at angles) and 2x layers on bottom each at an angle. I have abandoned the idea of using a composite skin due to my lack of technical ability. I see no reason we can’t have sub 4 pound shortboards. Just need to figure out how.
Yes corrugation is a way to increase stiffness. Stringer too. Sandwich skin is more efficient against local buckling. For ultra light and still durable board you must go the sandwich skin tech. I make a 25l shortboard at 1.7kg still in one pièce after lot of use. But everyone find it too light after some surf…
That weight is extremely impressive. I would love to learn in detail what materials you use and how you do that. Do you have a website?
One of the ways to get lighter boards is by vacuum lamination. You can get a high percentage of glass to resin. This would also help transition to complex composite skins that would add even more strength.
Deck channels will add stiffness and help boards from snapping. I don’t think it helps from getting pressure dents if the foam is soft. You can eliminate a stringer and use deck channels. Soft foam and stringers makes for bad denting on the deck along the stringer.
Good points, thank you. Does vac bagging remove excess resin or does it only evenly distribute what is there?