I dumped them both for wood.
Why d$%k around when I can just make one from wood and have it last a lifetime plus.
I think your referring to Gundangs iXPS foam or dXPS foam (or whatever it is that they are calling it now) which is supposed to be different to regular XPS. Mainly due to the fact that it is not supposed to outgas like regular XPS. I’ve heard it machines well but is crap to hand shape.
wood is good…
All blown polystrene foams like XTR or any EPS are the same as far as expanding when heated and water infiltration between the cells. If there is some “skin” surface imparted on a molded blank such as melted cells filling in the air spaces, it would not suck water provided that the skin is intact and the raw foam isn’t showing. Likewise for a blank sealed with epoxy and microballoons, or one with a D-cell lam over the blank. Unfortunately, most dings go into the foam so it is pretty superficial to say that any EPS (extruded, molded, or cut) doesn’t take in water. Any molded blank that is not directly glassed but shaped, loses its skin and behaves just like any other cut blank.
So what are the differences in common EPS blanks for shaping? (1) Bead size: This affects the shaping ability and ease of sealing - blades or sanding drums, and spackle/micro-balloons/nothing. (2) Density: Overall weight obviously, but also a small degree of structural strength on blank. Actually the idea of any structural strength in EPS itself is null, because unless you get to ridiculous densities it fails at very small shear or tension loads for a given thickness. The role it plays in overall board strength is that it controls the form of the glass whose shape really controls the strength. The foam also keeps the glass shape from collapsing under compression, which is why EPS is also used so much in packaging applications. Density is also a consideration in the shaping process in that you wouldn’t want to production shape SUP’s in 1 lb or less simply because they would be difficult to control on long cuts. You also wouldn’t need to bear the higher cost of 4 lb density for a shortboard that is easily controlled during shaping at 1.5 - 2.0 lbs.
Now, if you’re just buying a finished board and not shaping/glassing one, the choice is easy. Ignore all the BS sales hype and just get a regular EPS core. If you’re very hard on the deck, get the heaviest glassing schedule you can bear in overall board weight (you didn’t give the dimensions). If the glasser is bagging, get a D-cell layer on the deck.
Thanks for the reply Greg.
That"s the info I’ve been getting from some local eps builders too.
Quality foam is the key.
Cheers
Mooneemick
Read where you have a warehouse full of XPS blanks that you can not sell. I am interested in buying some lots of your blanks from you. Would you consider selling to me wholesale ? Thanks
Hey ErikG,
Sent one of the 6’0 preshape XPS boards up to the sunny coast in Queensland over here to one of my team guys and he was absolutely frothing on it, couldn’t believe how light and strong it was and he loved the feel of it. I usually glass his boards with a 6+4 +6oz front foot patch with carbon rails on the tail area deck. 4oz bottom over PU foam and he still crushes the deck.( I’ve never seen anyone destroy boards like this kid). I did the XPS board with 1x4oz with a 3/4 patch deck and 4oz bottom and it was just starting to get heel marks in the deck. This was just before he snapped the bloody thing, He was devastated and reckons he doesn’t want to go back to using PU foam because of the compression strength and the lively feeling of the XPS.
Regards
Daren
P.S. No delams either even in the Queensland sun.
Sounds like the go. Nice to hear it hasn’t delaminated.
Thanks Pete. The dims are 6’0" x 19" x 2 3/8". And I was thinking of glassing it 6/6/6 two top one bottom. Would that on an EPS core be about the same as a normal board? I don’t mind adding a pound.
What kind of blanks do you have? Are they flat sheets, rockered sheets, rockered and outlined, rockered outlined and profiled?
What do/were you charging for a blank?
Hi Mean: 6/6 + 6 is what I would do. To minimize deck dents, use S-cloth as your deck 1st layer and regular cloth elsewhere. Stagger the laps, and lap the deckside over in both layers. This will provide much more stiffness at the rails and increase the breaking strength. Seal the blank with micro-balloons + epoxy, not too heavy, and it should still be lighter than a 4/4 + 4 poly.
Quote:
Maybe you could clarify: When you state “Molded EPS”, are you generally speaking about all EPS whether its molded into huge blocks the size of a room and cut into billets to be then wire cut into blanks, as well as EPS that is molded in a mold the shape of a blank?
As far as XPS, back in the early 90’s I worked at 2 shops in Miramar. One that glassed Hi-Tech Sailboards the other that glassed Rustys. Both tried XPS which then was being marketed as “SVF”. It was eventually abandoned because of all the gassing/ delam problems.
I’ve heard recently that Patagonia/F Chounard is now offering the option to use EPS instead of XPS.
Begin Old Guy History Block:
“SVF” was coined by Pedro Vasquez of Peru. He and his brother ran Focus in Peru shaping and glassing EPS. He moved to Hawaii, where his wife was from. This was nearly 20 years ago. He was formulating epoxies and working with Dow on the earliest closed-cell styrene blanks. We actually glassed the very first boards here at his inlaws house with some of his epoxies. In the end he decide his business would do better in California. I think he moved to Oceaside. Gary Linden worked with the material a lot. Everyone tried it. In the end, the delam issue killed it. Basically the same stuff today, but the early cell structure was much larger than you see today. On a related note, what is now known as Aluzine (FGH epoxy), was Pedro’s CX-21, with some subsequent tweaks. They bought the formula off him fair and square, no matter what any one else tells you. He formulated the resin and it was one of several we tried during that period, and then years later FGH bought it. It was all legal, ethical and above board. I was there. We surfed and made boards and hung out several days a week. Pedro was the guy who first put the squeegee in my hand.
XPS - I don’t know why people on swaylocks talk about them? No one makes them or even knows how to glass them? DELAM? They don’t Delam?
It’s called Shear! Leave them rough 60 grit then glass. No smooth screening. Duh!
I have a warehouse full of blanks I made 3 years ago. EPS also. On Swaylocks people claim to make EPS boards with Epoxies?
I have 300 EPS blanks in 2.0 with 1/8" stringers. If I don’t sell them soon it’s time for the Landfill.
$25.00 each for the XPS 64’s good for Hand Shaping - You can’t even buy the materials for that!
$10.00 for the EPS unglued cut out lines - ready to stringer up.
I’m in the process of moving my shop and do not have room for my inventory.
PM me if your interested?
After next week-end I will purge everything.