i like it man
Looking at this old thread, it seems that “Zerovoc” claims that doing a couple seals on EPS will allow you to use polyester, vinylester or, of course, epoxy on their sealing agent. They show the video using microballoons with it and sun curing it.
They also have a sun cure epoxy which I am wondering if anyone has used at a productionlevel versus a hobbyist. Seems like the turn around would justify the expense as long as it is non yellowing and comparable quality to what is out there.
In the video with Mike Richardson, he shows using Zerovoc and microballoons on EPS doing two coats to seal well then glassing with one layer of TWO OUNCE ontop and bottom. I find that pretty unbeilieveable. Has anyone tried this? He shows how the Zerovoc crosslinks compared to spackle.
I know spackle is commonly used, but after trying it myself compared to an epoxy/q cell slurry, I have to say I think it is crap by comparison. Yes it is super easy to apply ultra lite spackle watered down, and it will allow you to have a great painting surface, but I really do not believe it can provide a second line of defense of minor dings nor bonds as well to epoxy laminates regardless of what has been previously stated in other threads. Epoxy to epoxy versus epoxy to spackle just seems like a no brainer.
But going back to this Zerovoc stuff… this is really worth a try or hearing from someone that has used it with polyester, and/or epoxy. Or at least if someone has done a thorough epoxy/microballoon seal, sanded that, then done a UV polyester glassjob? And finally, if not that, at least did epoxy laminates and hotcoated UV plyester directly on still tacky epoxy laminates?
Matt Campbell of Resin-X makes an undercoater you can use to seal an eps blank, and then glass over with poly. It’s pretty inexpensive.
Heavy coat Elmers Glue.
Been there done that it worked justfine
The board failed as a result of being stringerless light EPS 1 lbs density and lightly glassed.
White glue was commonly used 25 years ago until we found it dissolved when the boards got dinged. If you do stringerless you need to staggerlap wider laps on both sides to create perimeter strength. If you make your rails bulletproof in this manner you cn forget even having an I Beam aka center stringer… and you won’t get crushing of the EPS foam next to that stringer because it will be gone.
Does Resin X’s sealer have any kind of strength as Zerovoc seems to imply?
Also, in the Zerovoc video, the two coats MR applied added a couple pounds! That is a LOT of weight to add to a seal coat… but it could be justified if, in fact, it reduced the need for a heavy glassing schedule. Which I am still totally skeptical of that claim.
Two ounce on top and bottom? Did I miss something? Does he mean two ounce BEFORE adding your glass schedule of choice? That’s not what is shown in the video… it ends with showing the final weight of a good sized fish at (I think) 6.9 lbs. … great, except I can build a strong board lighter than 6.9 lbs, and not pay $90 a gallon for their sealer. Are you merely trading glass cost for Zerovoc?
So what is the real benefit?
The age old concern for using EPS is the vacuum that is created by disparity of inside and outside atmospheres. That led us to debates about the need to vent our not. So we now have Gore Tex vents in leashes that are unassuming but the debate continues because the discussion there was that the vents should be placed more toward the center of the board instead of one end…or there should be two, or even three vents throughout the board.
We also have personal accounts from people like GL, and myself included, that never vented boards from around the early 80’s on. This was using 1.5 & 2.0 lb EPS but before IDRO machines. I also used quite a bit of 1.0 and even some freak lighter stuff, without vents.
It is my understanding that the IDRO process resulted in a superior formation of the beads (round vs oblong/oval) that allows for better compression in the secondary stage to reduce airspace between the beads hence the term superfusion. Still, there is much debate as to the true merit of superfusion, comparing form molded blanks (i.e. Marko) and block cut EPS. Is superfusion as good in a block cut blank? Many believe not.
Why use EPS at all?
It comes down to the compression of bead formed versus cell structured foam.
Beaded foam has memory which allows it to recover (energy management) a blow or load bearing without permanent damage.
Fixed cell foam is prone to crushing. This too, is ‘energy management’, but recovery is not apparent.
Stiffer based EPS beads are more prone to managing energy in a similar fashion to a fixed cell foam, but not exactly.
More often than not, the EPS foam that does show evidence of crushing has either had a severe blow that surpassed the reinforcing skin’s ability to distribute load, and had blunt force enough to surpass the ability for the two to manage energy with full (or what appears to be) recovery. This can be incorporated into a product by design, as in the case of bicycle helmets that are designed to absorb shock rather than transfering it to one’s head.
Denting can also result due to force exerted adjacent to a fixed structure i.e. stringer, fin box, or some other ridgid structure.
It would appear that IDRO is important in the sense of producing a superior bead structure, while the compression should not be produced to the point that it begins to mimic the vulnerabilities of fixed cell foam.
Rather, it would be a far better answer to find a material that has the ability to penetrate and seal the air space in a shaped EPS blank. The ideal material would be flexible enough to manage energy ‘with’ the EPS, while penetrating the foam then expanding to seal the outer air space of a shaped core.
This is my current thinking versus having to rely on the application of a ‘typical’ additional skin that is vac bagged to the EPS core to create a barrier that is water resistant or water proof as in the comp sands.
At this point, I have been looking for a compatible ‘treating agent’ that will render shaped EPS with this inner 2nd line of defense that doesn’t represent huge weight gains, the need for vac bagging, a lot of weight, or a substantial increase in cost or labor. A low tech approach, have you, with high tech results.
Ideally this agent could be used on any type of EPS foam, whether IDRO produced or common building grade.
Cheap
Easy application
Lightweight
Epoxy compatible
This has been tried and tried and tried for over 50 years. It just isn’t a good idea. When sqeegeeing your flats, poly resin will find any insignificant hole and attack the foam. Not to say it can’t work once … but anyone who’s making any number of boards will get a low percentage out of any sealing method followed by polyester. Plus weight penalty in dealing with heavy seals kind defeats the whole purpose.
Matt did not suggest that the undercoater would offer any strength benefits, merely that it would seal the foam with a thin & light layer.
Then I don’t see any apparent benefit to buying the product unless I’m missing something. Cosmetically superior to epoxy/microsphere sealing? Better adhesion than ultralite spackle?
I agree with Greg, that sealing an EPS blank for the purpose of using UV polyester is inherently a loser. First I doubt that the bond will ever be comparable to an epoxy based glassjob. And even if one glasses an EPS blank with polyester resin, the end result will be a cheaper less durable product.
Like GL, I feel the dynamics surrounding EPS as a core material are unrealized and underappreciated. I don’t believe the different feel in ride is the deciding factor why EPS isn’t in commonplace use. So if it is in fact the fear that your board will be invaded with water the second you have a pin hole leak around a box, leash cup, or a tiny ding gone unnoticed… well, how do you counter that archaic thinking?
Instead, what we have are very expensive, highly sophisticated products like Surftech and Firewire and DIYer comp sands that use EPS cores then surround them with extensive outer layers. Some of these approaches are quite good while others are a joke. But as I suggested with my penetrating seal approach, we still aren’t getting to the core of the matter. Widespread use won’t happen if you have to vac bag everything. And if you produce EPS to a tiny bead size that eliminates nearly all the air space, you lose the inherent benefits of the material in the first place: lightweight, and memory. Is there a way to make a much smaller bead size that can be superfused, still with a 1.0 or 2.0 lb. density? Cost?
I have to wonder if Surftechs demonstration on You Tube comparing different EPS cores with the glass of water and vacuum isn’t the result of what I have suggested here. Have they found a penetrating expanding sealant that can treat superfused or even lower grade EPS? Or is it a further development of higher grade EPS that is so tightly compacted that it disallows water penetration/migration? If so, why bother with tough outer skins unless it represents massive savings and net bottom line profits? Ad if, this foam that has been “10 years in development” is exclusive to only them, why not just provide the rest of the world with it and make even more of that bottom line profit? Or, is it ‘just’ in fact IDRO produced superfused foam?
Why not just produce dual density EPS foam blanks that have a 2.5 lb. EPS density skin that you shape and a lighter EPS inner core, then bomb proof the rails where you traditionally overlap the deck and bottom glass anyway. Block cut, dual density, not real hard to produce, less glass schedule required if you choose to go that way. If you do it right, no need for stringer, and you save weight by omitting as well as cost offset for the dual density. Your ‘stringer’ now becomes the perimeter glass reinforcing making your rails bombproof. Poor man’s parabolics. If the skin is IDRO 2.5 lb EPS, don’t even bother sealing the foam.
GL, did I miss something… didn’t you already do this or Warvel and your association with them at some time?
The problem with Surftech’s demonstration is that the foam is NOT inside a surfboard representing a separate closed atmosphere subject to inner and outer temperature differentials.
The agents that I am exploring are used for situations that are prone to hydrostatic pressure and also instances involving gas. Water molecules can be stopped pretty easily with the correct applications of existing materials that do not cost an arm and a leg, and when it comes to our industry, this is always a key consideration. These treatments also deal with temperature differentials ona daily basis. And, they don’t weigh an arm and a leg.
P.S. Where can I get 2.5 lb. sheet EPS and do this on a couple hundred EPS blanks I have?
No…my takeaway was that if you found yourself in a weird situation where you were going to use poly resin on eps, he had a solution
He was NOT saying that it was the recommended way to go…clearly eps + resin-x is (at least imho) the way to go.
I appreciate the clarification.
I realize that many Swaylockians are into reinventing the wheel, but sometimes taking the low tech approach can yield high tech results.
I can understand that Greg has lived this for sooo many years that he probably could site 100 or more like a 1,000 of examples of diminishing returns while searching for the Holy Grail.
Call me stubborn, but after posting I emailed Segway and surprisingly, got an email back even though it is Sunday. However, I’m not interested inthe PU sheet foam approach that was mentioned and have asked for quotes on 24"x96"x.50 2.5 and 3 lb. EPS sheet foam.
In the meantime I googled a few other sources and got one with a caculator that had 24"x96"x.50 at $6.38 per sheet but 2 lb. density was the highest density they were showing. There was also a $250 minimum requirement.
Segway advertises 2.5 and 3 lb. EPS. I figure if I look at this approach vs. the more common vac bagged 6 lb. PU sheet application, I may have an easy shaping dual density block cut blank that offers excellent strength to weight ratios, the choice of a lighter or stronger glass schedule, and optional choices of materials to create the dual density blanks. Like 3 lb. over 1.0 lb or 2.5 over 1.5 lb. or whatever…not to mention a choice of lamming the sheets together with different oz. cloths or Roo Glue, epoxy, etc.
Not a bad product to consider?
During the 80’s, while working at Lindens, we sealed a EPS foam blank with Elmer’s glue and rice paper used for laminates.
One layer on each side just like a lam job.
Sanded it.
Painted.
Glassed with poly as usual.
No leash plug. Leash loop instead.
Super light.
Did not last long.
Epoxy is stronger.
if your using glass fabric, seal that blank with Skinz flex ply + epoxy and then lam it like a poly board. But if you ask me, you’re using epoxy already, just laminate and hot coat it with epoxy.
I don’t get switching chemicals mid-step. Might save you a few bucks, but you’re losing time trying to figure it out. And EPS is weak unless you’re in the 2# and up range. You’ll want a lighter resin anyway.
Epoxy, it’s stronger, and you’ll cash it on the reef long before it yellows.
I have tried every glue or resin than I am aware of Bruce , and still try anything new that crops up…Ive yet to find anything as good as thickened epoxy for strength to weight , without sacrificing performance in any way…it also leaves you free to choose any density EPS , and adjust the amount of thickener accordingly…epoxy to epoxy bonding is a non issue…the biggest advantage is epoxy primer will retain total flexibilty and memory in the context of the whole completed skin , as an independant feature of the boards performance…whereas PVA , spackle or PU will seal, but detract from the feel or flex characteristics , giving the board a dead feel , in comparison…that’s what I have found , and beyond that , the road leads to dual density blanks or my current favourite , Surfblanks pink , which seems to solve so many problems in one hit…
I seal it with wood & epoxy.
I know this is from 2010 buuuut…
I just want people to know about ZeroVOC from Wahoo int. you just put it directly on the EPS and it seals it completely, then you can just glass with Poly resin like normal!