I’ve built boards in the last year out of both insulfom brand and some kinda generic eps insulation I bought at a hardware store. The insulfom (from home depot) #1 density eps was super bouyant and didn’t absorb water from any dings. The other stuff however was an entirely different story. I had a weak spot in the lap right where my left hand grabs on for duck diving that devoloped into a little hole. everytime I squeezed the board (low density eps) it would suck in water. Lotsa water. The board gained pounds and sounded like a rain stick when you turned it from side to side. It was pretty funny actually.
I’m a fan of EPS, but it is still possible to find EPS that will absorb water from pressure changes caused by being encapsulated. The factors in manufacturing EPS, EPE, and EPP include time in the steam chest, number of core vents in the tool, vacuum volume to evacuate steam, temp of steam, loading the tool to proper volume etc. The beads are closed cell, but with lower densities there can be capillaries between the beads. It is risky in the 1lb. range. At 1.5lb. on up the beads are usually packed tight enough. Back in the early '80s, Hydro Foam sold pressure purge valves as a partial remedy for their blanks. I say buy the EDRO foam to be safe in the lower densities. Love,Delbert Pumpernickel
im with greg 100 % xtr is a dead horse…its producers dont even consider the surfboard market ,i cant see how any extruded foam could be applied to surfboards ,they would have to change there process entirely to elimate polyethylene ,before it would be any good to us…
as far as eps is concerned …i see it as far superior to p/u coz when it gets wet it doesnt deteriorate over time ,like holly said (what i think he said) i havent seen a water proof eps yet ,you can make it water proof but it comes back to weight,the more water proof you make it the heavier it gets…
again backing holly’s comments ,the lighter it gets the larger the void space between the beads,im using about 3/4 lb foam the lightest stuff you can get…
all eps sucks water or blows bubbles it just depends on the temperature difference ,the core will always want to equalise with its surrounding ,if you have a vent then the temperature difference between the time of closing the vent and later dinging the board will determine what will happen …
if your board is hot when closing the vent then you enter cool water it will want to suck like a syringe when dinged ,but if you do your vent up when cold and enter warmer water then your board will blow bubbles when the seal is broken…
so the lighter the foam the more air inside between the beads the larger the pressure difference and its ability to suck or blow…
now if your board is unvented ,then it comes down to the temperature of the board when the builder finally sealed it for example(years back i went thru a stage of not venting my boards because some people were forgeting to do the vents up and getting water in there boards,we started baking them before the final glass job exhausting all the air ,so if a guy left it in his car on a hot day it wouldnt blow up with pressure,anyway this guy goes 5 summers with no problems then he rolls in and is dumbfounded why his board blew up in his car on a warm but but not stinking hot day,i asked if hed dinged it recently ,he said yes and he fixed it himself ,but by dinging it he allowed air into the board then when he sealed it at a lower temperature there was a greater pressure build up when the board got hot ,that why it didnt handle the same extreme heat it had dealt with before,so now there all vented and its the customers responsibilty)
but heres some of the trade offs .
even tho heavier eps wont suck as much volume of water ,when its does its harder to get out but the lighter eps sucks way easier and quicker ,but because the void between beads is so much more open its easier to get the water out again…
the simplest way ive found to get water out of eps is ,air pressure…
i have a connection i screw into the vent hole ,hook it up to my air compressor (after dialing the regulator right down)…
by blowing low pressure air in, you just blow the water right back out the hole it came in,then the moving air through the core dries it out and gets rid of the last traces of moisture…theres some other interesting quirks with eps but ill post it another time ,im pressed for time right now…
regards
BERT
Holly has the knowledge, Bert has the answer. EPS has two week spots. a) the cell (or ball) itself and b) the space between the cells/balls. there is also a third factor to be considered, the use of recycled material in the manufacturing. try to get recycled free, leave the other stuff to Mac Donald and insulation where it comes from. Next get an EPS blank with sealed cells, whatever technology is used (depends on the country/continent). and next, choose an EPS with a decent cell size and cell compression which reduces the size of the capllars, the space between the cells. if you have sealed cells and minimal space between you have good chances 4 success. the material is not ideal as the sealed cells in my experience have a reduced cell bond … now you get the picture.
Bert can remove the water/moisture out of the capillars with the air pressure method but nor the moisture out of the cells. left moisture develops into steam - develops into reduced cell bond – delam!!
Good EPS left in the water will stay good till 2020 at least but when you laminate it you start the pressure and temperature inside/outside problem and in surfboards/sailboards you stand on a big pump with every move. great material for short life boards/prototypes but never cheap in the long run. except you treat it like my neigbor treats his car. and yes, xtr is a dead horse.
sorry.
With all due respect to everyone out there, looking at all the back and forth on XTR, EPS, Salomon, etc. I find it kind of humorous. On the one hand everyone is slagging the industry in general for staying with polyurethane and fiberglass resin, and yet on the other hand anyone who tries something new gets jumped because they don’t have the final “end all, be all” new material. So what if EPS, XTR, etc. are not perfect? What’s the alternative? And who gets a product right the first time without growing pains? At least these guys are out there trying. Besdies, I don’t recall any of them saying that their current product was either the final iteration or the perfect material. It’s a work in progress. That’s how things generally develop. Small steps.
Why don’t we simply cut to the chase and just call every new material a “dead horse”. Then we can just go back to using Volan and boat resin. There now, is evrtybody happy?
Please pardon the steam blowing. It is my intent to inject a dose of perspective and perhaps humor to what has seemed to become a very heated and perhaps overly focused debate. Again it’s my 2 cents (probably only one cent in this case). Besides, this forum and the free exchange of ideas and opinions it represents is what makes America great.
Let the games continue…
Quote:
Please pardon the steam blowing. It is my intent to inject a dose of perspective and perhaps humor to what has seemed to become a very heated and perhaps overly focused debate. Again it’s my 2 cents (probably only one cent in this case). Besides, this forum and the free exchange of ideas and opinions it represents is what makes America great.
Let the games continue…
More like pentane blowing…
hey Mmanzy,
sorry if I stepped on your toes. did not mean to. and i do not say lightly what I said about XTR (and the very related XPS). see, I was very excited about this material back in 1978 when i made my first board out of it. the hope and frustration lived on till about 1990 when I finally gave up on it. there were thousands of people and companies out there trying to make it work and countless solutions have been tried but in the end gain and pain did not match. there were some people quite successful by integrating it in a sandwich design but if you go through that much trouble good quality EPS beats it in every aspect. I had a little supply company for the surf and sailboard industry in europe for about 10 years with over 1600 customers from sweden to the canary islands and a healthy R&D budget. and i sold that stuff and got a lot of customer feedback, that’s why I think I know. but i might be wrong and “never give up” applies here too…
No offense taken, I was merely commenting on how narrowly focused and intense this whole thread was getting in respect to the overall issue of material development. I do not have a proprietary interest in the XTR or epoxy systems. Brewer/Plumeria does in fact sell XTR boards (and our feedback from the Hawaiian teamriders who ride serious surf has been very positive). But we also sell conventional polyurethane/fiberglass, balsa, etc. Dick is also currently involved in testing boards using aluminum honeycomb/kevlar/carbon construction. The key is that we’re open to it all, and it’s an ongoing process. We are basically trying out a lot of different materials in search of something better than what we have now. To me, having an open mind is the key.
thanks mmanzi for not throwing me in the bin as the a-hole of the century. you are right, the discussion showed a bit of narrowness and frustration. I think it is the misrelation between hope and success with some of these materials but I like to see all those good things happen in surfing. the aluminium honeycomb and honeycomb in general are excellent materials for surfboard sandwich. I had 2mm and 3mm sheets for sale and it was , not very expensive. It is also a good material for the handyman as it is very easy to work with and needs only a low vacuum pressure. it can also be successfully combined with other sandwich materials like veneer, bamboo or pvc for the bottom as the honeycomb easily wraps all around the rails. real good fun and very high successrate. sorry for the misspell too…
i agree , honeycomb in my opinion is the most credible option , the comments ealier about the cell of eps ,each eps cell is a sealed unit , pentane gas is used as the the expanding agent ,its forced into styrene at massive pressure and when taken out from that pressure it expands the styrene into bubbles , after a few days all the pentane is realeased it difuses out of the cell (similar to how a helium baloon goes down),the cell then becomes a sealed unit to water ,like a ping pong ball ,the h2o molecule is to large to penetrate the cell , but as said before if recycled material is used in eps then you have broken cells mixed in ,some companies run up to 20% recycled material in there cheaper foams , if your vacumn bagging ,the recycled foam will cause major headaches as it responsible for the foam collapsing under vacumn ,whereas 100% new bead foam will hold form under vacumn coz each bead is trying to expand into the vacumn…
ok thats me for the day ,
regards
BERT
ps depsite whats been said so far ,its my opinion that xps/xtr will continue to be that pot of gold at the end of the rainbow ,it seems to have so much potential ,alot of people have put enormous effort into making it work ,my first encounter with it was around 1990 , i tried real hard for years to make it work …i was surprised to read someone was trying it out in 78 ,i think that just confirms my theory more…
its like the race for the superconductor …
its probable someone will nail it ,its just alot of people have failed trying…
I was in the Plumeria shop in Cardiff, there was an XTR foam, team riders board, with air vents, split next to the stringer, caved in and delaminated, all in the course of 2 weeks of riding. Like cro-magnon, an evolutionary dead end, EPS, poly-urethane, woods, all other branches, some doing better than others, some destined to extinction
Jim: Again with all due respect (and this is probably the last thing I’ll say on this subject), I’m sure that you can find broken boards of every construction if you look at enough boards. We don’t claim that the XTR boards are indestructible, and some of the team riders are really hard on equipment. As for the particular broken “Team” XTR at the Plumeria shop, we try to keep them for Javier to look at, because studying the broken ones is what tells him where the weaknesses are and possibly how to make improvements. Again, my point is that to give up when problems are encountered only leads back to the status quo. But by carrying the form to it’s developmental conclusion at least teaches us something, even if in the end that form winds up being abandoned.
thats a fair comment Mmanzi.thats where swaylocks will no doubt be an invaluable tool …no longer do as many different individuals have to feel the pain of reaching that dead end…but sometimes reaching a dead end for yourself is still satisfying ,even if just for the fun of exploring…
regards
BERT
When it comes right down to it the “Holy Grail” of high performance will not involve XPS or a simple EPS or urethane core but will involve a combination of materials within the core. The idea that a single material core will somehow revolutionize the product is simply naive. Cored epoxy laminates are at the heart of the real future of high performance boards (right Bert?). This isn’t easy or cheap and the real challenge will be to blend any new technology with the existing custom industry. We are seeing the first attempt, with regard to cores, in the Salomon project. There will be others. Our goal at Resin Research has always been to develop the resins with custom building in mind. To throw away the custom industry would be throwing away the baby with the bathwater. There are too many reasons to keep the industry custom and too many advantages for the consumer. Surftech is the best example of the disadvantages of a non-custom industry while being the best example of the advantages of cored epoxy laminates.
Also the narrowness of this thread leaves out the fact that the future surfboard will be made a number of different ways for differing portions of the marketplace. Epoxy laminates will allow the future custom manufacturer to offer a number of products with differing technologies and prices. MManzi is expressing an embryonic version ofexactly this. It is my opinion though that the technologies that are being used today are being used by companies out of convenience and that those technologies that are available are ALL lacking. Their shortcomings are what lead to the constant debate here on which has the overall best features. My personal experience is that EPSdoes but that’s just my opinion and certainly EPS has it’s shortcomings (mostly cosmetic). Urethane does as well (weight, delamination and a fragile shell). XPS has heat/delamination issues.
Which brings us to the subject of the depth of R&D that we as an industry are able to afford, which isn’t much. Saloman put up 1.5 mil on the S-Core project and whether they hit or missed the mark, what is shown there is what is possible with some development. The fact that we are all dealing with technology that is lacking denotes the lack of development and development money that has been spent. This includes all technologies presently available including urethane. It is obvious to me that to make the jump to the next level surfboard will take a combination af technological skill and creativity combined with the financing. This is what changed the sport in the late 50’s and the consumer paid for the advance. Today the consumer ultimatly will pay for advancment but the method of developing the technology is vastly more complex and the financing any project is increadibly convuluded.
Still, many of the ideas expressed here have merit and the exciting part of today’s industry is an openness towards new ideas. This hasn’t always been the case.
wise words spoken by GregLoehr. the door to the future is open and on the way there we will be able to use what we learned . In this field the ones with the dirty hands will rule and every broken board, every mishap, everything that did not work creates the road. have a look at the following webpage, something like this could bring a change
yea greg i do agree …and like you said more people than ever are open to new ideas ,and like jim alluded to ,a larger number of people are having success with different combinations of composites ,so others are realising the potential…
the cores of boards are the current achilles heel ,all the current foams have there fors and againsts …i agree with you on that point to greg …eps is the best of a bad bunch…
i may end up regretting this ,but at the same time it could lead to something if i speak up…
ive been doing alot of work over the last 6 years with honeycomb…
but not anything you can buy,ive been making my own ,working on full honeycomb cores…
basicly each cell runs from deck to bottom, so if you had a clear glass job youd see right through your board…
things like cell size , cell wall thickness ,and the material of the cells ,ive had to nut out ,not only for shaping convenience but also for weight and strength…theres a range where it functions well ,if the cells are to big you need a thicker heavier skin…if there to small it gets heavier but the skin thickness and weight can be reduced…
here come the advantages,wont delam coz of incredible peel strength ,coz each cell has a slight amount of resin just inside the opening bonding it to the skin…( xtr’s biggest problem)
doesnt dent ,pressure ding,go brown or decay with age if it gets wet (p/u’s downfall)
wont get waterlogged and soak water if holed ,because each cell is a sealed unit ,if its broken you just empty the water out and fix it…(eps’s blight)
it solves all the current core problems …my only problem at the moment is cost …
the amount of work involved in making the core material is huge , plus my curent methods of doing it by hand mean that sometimes i make mistakes and ruin 4 or 5 hours work…as it stands now it wouldnt be cost effective to make ,ive been doing my own personal boards and other sample sections …
im at the stage where its ready for major tooling .i can envision machinery that would produce the cores easily …(i havent found any existing honeycomb that does the job)
the only problem is i dont wanna tie myself down…
another problem is , flex ,float, shape to match the performance characteristics …the stuff is so dam stiff…so much more needs to be done…
its like i need cheap easy access to the core material before i can make the next steps quicker and easier…
obviously you get best results when vacuming on a skin , but you can shape the stuff with a planer and sanding block , and i did one sample section with rice paper over the cells then glassed ,so it has the potential to have boards built from it in a low tech way as well ,similar to poly p/u construction…
i think for a product to be viable for an investment situation you need to be able to sell it to everyone not just high tech producers…
this project needs way more input from others , as well as cash…
my problem is im a r&d guy , i really cant see myself in the business end …
i love being in the bay and in the water…
anyone got any ideas???
regards
BERT
Hi Bert - Sounds like a classic dilema. From what I understand our current mass technology came from the military out of WWII - and I am not sure where the hex-core aluminum that has been used in skis and ?, came from, but I would guess it was not the ski industry. Have you thought about other, perhapse larger, or a varity of industries/fields, i which your “core” would work? For quality and consistancy, and quantity and affordability, it seems $$$ for R&D, tooling, etc. would be crucial, and if you were to “shop” it around you might find some buyer(s). The beauty of your position, form what I read, is you are not worried about getting rich, or keeping a patent, or… If you are willing to share, well… It gives you much more leeway. Although, if you were “insanely” commited to being “the man” on this, it might drive you to find the answer.
After re-reading your post, I’d say - if you could get someone with the resourses to “buy into” the idea, and bring it to a level of affordable quantity and quality, we might all be in luck. In the mean time, good luck, and continue with the quests! And, thanks for all your sharing.
Peace, joy, and love - Taylor E. Olson
Bert,
If you don’t mind me asking which material honeycomb you using? I’ve used the paper and Nomex, but that was long ago. I’ve also seen aluminum. They use that at the Cape a lot. Some of it just has an impregnated paper over it. Light, one time use stuff. Each had it’s disadvantages so I never followed it up. We were also doing some honeycomb with wood veneers which came out increadibly strong. We could jump from a ladder onto a thin panel and… nothing! I’ve recently seen some propylene honeycomb that looked like it had potential. Some of the sheet stock comes with veil already in place.
Bert, why have the honeycomb pattern from deck to bottom and not rail to rail? It would probably be more difficult to construct, but wouldn’t that do more to take advantage of a hex pattern’s strength?
sorry about the link that did not work. try this one
http://www.roehm.com/en/performanceplastics?content=/en/performanceplastics/rohacell
go to technical data and now you have to register. look for
X-Cor TM Advanced Sandwich Core Material
this is what the big boys are playing with and it shows very well how they do R&D.
I remember that I got drunk blind one night in the early '90s with Greg Trotter as we did hold a sample of the ultimate surfboard core in hand. super everything and we called it ACRYLON (was actually Rohacell). was a good night so and the next day we made reality tests with the material. it can do everything but… like us it likes to drink. just fix that little problem and you will be rich and famousand you can forget about “gassing problems”…