You can laminate (ie Fiberglass) any Polyurethane Foam Blank, be it US Blanks, Millennium or Arctic with Epoxy whether it is Resin Research, Duraclear, Fiberglass Hawaii or Surf Supply( their respective brand names escape me at the moment). You are not pouring TDI or MDI foam into molds. If you are smart you are using at least an N95 mask or Charcoal filter Binks or 3M respirator. Possibly a vacuum on your planer. If you are shaping only the occasional blank, the danger of inhalation of inert foam dust is a minimal risk. Never the less; Take appropriate precautions. A properly stringered Polyurethane foam core, glassed with a quality cloth like BGF Aerialite, JPS or Hexcel is the strongest standard in the Surf Industry or the Backyard either. Yes there are othe skins and composite layups that are even stronger, but that’s not my point. My point is to remind everyone that Polyurethane shapes easily and cleanly, with less effort and does not have to be glassed with Polyester resin. I here so many on this site discussing EPS blanks and Epoxy but rarely hear anyone referring to Poly glassed with Epoxy. So I thought I would say AGAIN; You can glass Polyurethane with Epoxy and the finished product is superior to EPS glassed with Epoxy or Polyurethane glassed with Polyester Resin. Lowel
Good post.
I mostly do PU/Epoxy. I only do EPS when there’s enough volume for it to make a difference AND the additional weight is detracting from the design - which is not most of the time.
It’s like you said a couple years back: shape comes first, and it’s the core AND the glassing, not just one or the other.
Where is the additional weight coming from?
Let me just add-
The best is a correctly sized respirator with Organic Vapor cartridges and prefilters.Okay, there are pressure-fed rigs with filters and fans and hoses that lead to an overpressure full-face mask, those are better, especially if you’re working in an Ebola lab or with something else that’s horrible, but realisticly, respirators are something you can afford and good enough for this
The Organic Vapor refers to fumes from carbon compounds like epoxy or polyester resins, solvents and similar good stuff, the prefilters keep dust at bay such as foam dust, little bits of glass fiber and resin dust from sanding. None of which are exactly vitamin-packed. Their effects are often cumulative and addative - everything you inhale, all your life, it adds up.
And you don’t want to be old and hacking up crud. Kinda messes with your dating possibilities. You also get more prone to pneumonia, COPD, emphysema, some kinds of cancer and other fun. Not the best way to meet hot nurses. Really.
Suddenly the respirators ain’t all that expensive after all, now are they.
The prefilters also keep your organic vapor cartridges from clogging and a premature death. They are cheaper than the vapor cartridges, use 'em. Replace when they get clogged, like when they restrict airflow.
If the respirator is working right, you shouldn’t smell anything. If you can smell the resin fumes, it’s one of three things:
Your mask is the wrong size or used up: check by covering up the inputs ( filters) with some plastic wrap or similar, it should stay on your face with just the pull of a good deep inhale. The rubber may stiffen up or crack with age, like my back, and air gets by. In either case, get another one. I’m still waiting for the replacement back.
You have the wrong filters, either they are the wrong fit for that respirator or the wrong kind for what you’re working with. They should have part numbers, as does the mask- look them up. The people who make hem have a hilarious amount of information available, I think they are required to.
Your cartridges are worn out. It happens to us all eventually. You can make them last longer by storing your respirator with filters in an air-tight container, like the big zip-loc bags a lot of them come in. But when the time comes, replace them, cheaper than lungs.
They make full face respirators too. Which you can get peel-off covers for, clear plastic that keeps them from getting scratched up, dusty and spattered with resin or paint or what have you. The fumes and dust ain’t good for your eyes either.
Now, in the midst of the current pandemic, good respirators and components are a little harder to come by. Me, I stumbled across a serious sale on full face 3Ms back in the fall of 2019 and jumped on it. Dumb luck, I had a fiberglass boat rebuild coming up. Do the best you can for now and upgrade when you can.
Trust me on this one. Breathing is good. COPD sucks.
doc…
An other poly vs eps ?
May be time to look were it is, everyone Can acced and use those materials so…
What i see is imports liked eps/epoxy ultra light carbo tech (even more fake carbon), may be because it cost less to build than the old “cheap” PE/PU. The good is those boards are more and more garbage and more user come back to local build most of time better build even poly or eps.
Eps must be a cheap light foam used with thicker durable skin, boards ended dings and dent stronger but more sensitive to heat and water drinking. They must have a différent feel than PU core boards. Each one’s have is + and -, each one’s well build can satisfy user. There is not a good tech and a bad tech there are well and wrong made boards as there are good and wrong shapes…
I agree with you Lowell. All of my shortboards (Kitesurf) are built with PU blanks & Epoxy (vac.bagged). I feel that they are stronger than an EPS? Epoxy board & for me are easier to shape & finish cleanly. The only time that I use EPS is when I’m building a large board like a SUP when I’m concerned with weight.
I was referring to PU blanks being a little heavier.
- the standard for all of Rusty's team boards, aside from feather weight grovlers for gutless conditions, has been epoxy over PU foam for a long time. And pretty much every board out at Mavericks these days is made the same, the break rate much lower than PU over PU.
Not making an EPS vs Poly statement. Just reminding people of this very strong lamination in a normal hand layup. The combinations you use are super strong no doubt. But I am just referencing a Poly core laminated with a 6 and or 4 oz E or Warp cloth hand layup using Epoxy Resin. Typical of what could be done in most factories or any garage/backyard. Not a one versus the other. Just a reminder. PS. Yeah should have titled this thread different. Disregard the VS.
I had heard that. Might dent but less likely to snap. Those team boards might last longer that way.
…I have seen yellowing besides the wood stringers with epoxy over PU.
-epoxy resin for surfboards is not available in most countries like polyester resins.
-epoxy resin for general pourpose is not recommended for surfboards.
-ding repairs on those boards can be a problem in most places without the right resin.
-team boards normally do not have polished gloss or other quality finishes etc
they call it Epoly I believe.
Ok
- no hipster beards ( allows small particles through )
I was posting Epoxy over Poly buids on here a decade or more ago.
+1
Good point made by McDing in the OP and something that bears reminding the rest of us of -> +1.
Come to think of it, it’s something the general surfing population could probably bear reminding of too; don’t see too many Epoxy over PU blanks being offered off-the-rack and a more durable board does help make for a little less polluted world.
Good comments and info by others too along the course of this thread, and in particular +1 to Doc for his; I think I recall in one of Bert Burgers threads from year ago he made the statement that PU blanks contain small amounts of cyanide in the foam cells and that as you shape it you’re liberating tiny amounts of that cyanide into the air around you; something you may be able to get away with as a once-every-so-often DIY backyard shaper, but in a production environment the accumulative odds are ones I wouldn’t like to be taking. So rug up with what you need to get the protection you need -> 'onya doc :)
Hmmm- you got me interested regarding polyurethane and cyanide. And in that interest, well, I used to work for a fire science HAZMAT chemistry expert in college, as sort of a lab TA, I looked it up.
Okay, polyurethane in and of itself doesn’t contain cyanide, particularly the very toxic hydrogen cyanide. It does contain the building blocks to make it, carbon, nitrogen and hydrogen. Now, if you decompose polyurethane, say set it on fire, yeah, toxic levels of HCN plus the ever popular carbon monoxide. Known hazard in the firefighting business.
So, don’t cook over a campfire made of foam scraps, right? Especially indoors? Well, yeah, but if your tools are dull, planer blades or sandpaper for instance, you’ll be burning a little foam. Not much, most will be chopped off even by something dull. And you’ll be making cyanide, but not much. Probably where the idea comes from of cyanide being produced when you work polyurethane foam.
Thing is, there’s cyanides in a lot of things.Fruit pits, flax seed, cassava treated wrong. The body breaks it down as long as you don’t have repetitive exposures . But still, best to mask up while shaping or working with foam, the dust itself does plenty of bad things when inhaled.
hope that’s of use
doc…
Might not want to hot wire PU foam – cyanide release with thermal decomposition.
https://archive.epa.gov/epa/saferchoice/potential-chemical-exposures-spray-polyurethane-foam.html
https://firesciencereviews.springeropen.com/articles/10.1186/s40038-016-0012-3
Couple of thoughts from my experience with Epoxy over Poliurethane both making boards and from my son riding boards made using this method from a big name company.
1. The boards dent rather than shatter. This has plusses and minuses. Poliurethane foam does not rebound from an impact the way EPS does so when there is impact with your E/P board the foam compresses and just stays there where an E/EPS board the same impact may rebound and not leave a dent at all or the dent may be less substantial. On team light E/P boards I’ve even notice that they get what I’ll call finger dents from where my son will grab the board firmly while in the water.
2. While epoxy resins have improved dramatically in this regard, they still discolor very quickly. Again, nothing like the boards of the past but still not something I would want happening if I was a retailer. Epoxy glassed boards that have been on the rack for a while stand out like a sore thumb near fresh PU/PE boards. Also it becomes quite noticable if a board gets stickered up and then the stickers pulled off. I know that’s kids stuff but I’ve got one of those and when he pulls his sponsor stickers off of his epoxy glassed boards to sell the board or to just put fresh stickers on its glaring at you even if the board has only been in use a couple of months. Again this is nothing like how badly epoxies of 10 years ago turned amber but still something to keep in mind.
3. There is no way around it, doing proper repairs to a board glassed with epoxy is just a pain in the ballz. Extra prep and extra time to get the board back in the water. Yes there are UV epoxies now for repairs but I’ve found them to be miserable to work with and best suited for a quick patch approach. I’d rather do repairs to PU/PE boards any day of the week. I do repairs for friends and kids in the neighborhood and when friends ask me to do repairs to their epoxy glassed boards I tell them to take that one to a local shop for repair. I just don’t even want to bother.