"Too bad Gregs in Australia right now so well have to wait for him to get back to hear his opinion on the cottege cheese effect. "
we have the internet here too…
i have had the above mentioned problem with FH epoxy and PU. the boards super strong until 3-4 months then the foam just collapses.
this is just my opinion
thinking about Cottage cheese
i have had that before repairing boats
i think it comes from humidity or moisture
in the hardener possibly not mixed enough
just some thoughts but deffinately check and make sure your blanks moisture content is low
cause if you store them in say a damp garage or something …
anyone else got some ideas???
feral dave
doesnt the foam in a poly blank collapse eventually even with poly resin?
ps i saw a pic of one of your boards .looks good
Howzit?!? See what I mean? I’m figuring that since the RR material first came out for use to the general public, (the epoxy revolution) that it would take a while for the problems to start showing up. Since people around the world have started using epoxy as an alternative to p.e. within the last year, that by right about now we’d be seeing some weirdness. That’s why I started asking questions about these kind of things. Although the epoxy resin is way better than the standard p.e., it just isn’t as compatable with p.u. foam. Bert summed it up by saying that the resin is too advanced for polyurethane foam. I had been hoping to use RR for all of my p.u. blanks, but now I’m sending them all to my friends that glass with p.e. I can’t afford to be replacing boards that end up with junk glass jobs. Just as well for me, now I can concentrate on developing my styro/epoxy boards, while shaping (I hope) lots of p.u. this winter. Aloha…RH
Howzit?!? Over here, we definitely have some high humidity. Kokua is out in Haena, where it’s extra moist. Winter is kind of nuts sometimes, everything is damp. Some guys use a de-humidifier to try to keep it all dry. I am more convinced of the super-seal effect of the epoxy, trapping air, and water, inside till the foam starts to disintegrate. Also, as Bert said, the internal shear between the resin saturated foam and the inside foam, is a prime killer of p.u. blanks. Like he said, the epoxy is just too good for p.u. foam. Aloha…RH
We offer a UV absorber additive that makes the resin more urethane friendly. Most of the problems your seeing have to do with the extreme senstivity urethane has to UV. A half hour in the sun and unprotected urethane begins to deteriorate. The glass and resin help protect but a UV absorber should be added. So adding the UV additive will solve most of these problems. We don’t put the additive in because it’s only needed with urethane foam and is somewhat costly. So we sell it as an additive.
We went through most of this years ago in FL and everyone pretty much dumped urethane foam because 2# EPS is so superior. Lighter than ultra and as strong as blue and very stable to UV, heat and other exterior baddies. The Texas guys also all use 2# EPS and went through the urethane issues as well.
When you start looking at what foams are available to the surfboard industry and you really begin to build a lot of boards it doesn’t take long before you begin to see what the best product are for different applications. All are usable you just have to pick the right one for what your doing and the base product thats used day in and day out for standard epoxy boards (not sandwiched) is 2# EPS. It’s just the most reliable and has no issues to negotiate.
Best strength to weight
Best UV stability
Best heat stability
Best resistance to delamination
Doesn’t require extreme lamination schedules
Doesn’t need venting
Doesn’t leak through dings
Shapes nice
Easy to hot wire
Rides fantastic
Allows for advanced composite shells (carbon) and better interior reenforcments like perimeter stringers and suspention systems.
Available widely through EPS manufacturers worldwide
Available through many blank manufacturers all over the US:
RR FL
Coda Core FL
Chafin Distribution TX
S-Foam TX
Segway Composties CA
Hydrofoam CA
Shuler Systems OR
In The Eye NC
Just to name a few.
And there’s also new tech coming on line with other EPS cores too. Jtroy mentioned Jim Richardson and Jimthegenious has been working with some guys as well.
Then there’s the stuff from Berts corner … unbelievable stuff! Best strength to weight and beautiful flex charateristics using lighter weight EPS with sandwiched laminates. Ferraris!
So the future has many faces. Stay tuned.
Howzit Rick, I can see it now, if I used a de-humidifier I'd be empting the bucket every half hour, I just stop glassing when the hygrometer hits 95%. How about what the humidity does to sandpaper or waiting 2-3 hours for a paint layer to dry. Next time you stop by we should talk epoxy. Aloha,Wildog
Thanks Greg. I do remember you mentioning the additive for urethane foam. Hopefully we can get some over here to try out. Although I’m trying to get the techno aspects moving, I still need to shape lots of p.u., especially to finance my R&D craze. It would be nice to be able to use the RR on the things. I’ve got some shop changes (like find a new one) coming up, and I need to be able to continue to work on this whole system. Just started learning the APS3000 program, and I’m hoping to start making some rocker temps so I can get the hot wire cutter going. I can get foam from O’ahu, so actually the pieces are starting to fall into place. Typical story of under-capitalization though. Must work harder! Are you coming to Hawaii this winter? Maybe see you then. Aloha…RH