I got a pm on this, and since I finally loaded my photos last week, I figured I’d post it as a topic. When I first started this project, I read (in the archives here) a lot of different information on EPS blanks. Here’s how I did mine. And it all worked great - I’ve logged 6 or 8 sessions now and am enjoying the board.
I was asked how did I make a surfboard so cheaply ($143). It was all in the blank cost. I bought 2 8’x4’x2" white bead-foam insulation panels at Home Depot. $7 each. I cut them first to width - 24" - and then made a “V” cut in two to make a top piece > 8’ long. The “V” rather than a butt joint, so it wouldn’t be such an easy break spot. I stripped off the plastic film and glued them together with Elmers which worked fine. For clamping, I just piled crap in my garage on top of the two panels. I let it sit 24 hours.
I made a stringer out of overlapping (for length) pieces of 1/8" plywood door skin. I pre-shaped them for thickness & rocker so I could shape the foam down to the wood. I cut the template outline of the foam before gluing in the stringer so if I screwed it up somehow (big tearout or whatever) I could get more foam & not waste the stringer. I just used blue tape for clamping, and again Elmers for glue.
That’s all. A $14 blank. (And enough foam left to make another, 8’0" x 24" x up to 4").
I thought about using those same panels in another way.I would band saw out slabs with the rocker curve and glue the pieces together (face to face).I thought about using veneer between the glue lines for a mutli stringer effect.You could stagger joints if you wanted longboard.
I also got pm’s from rfd with a really cool idea - put a horizontal resin & glass stringer between the panels and use that to ‘glue’ in the rocker (with weights as it sets) and add strength. I might try that to make (lay?) an egg with the foam I have left…
I tried the electric planer first and it would have worked fine. I admit it, I’m impatient and was only risking $14. I thought the grinder would be faster than walking back & forth a million times and then sanding off the lines. I also have a lot of power-tool time and was pretty confident that I could hold it steady. The planer would indeed have been much more predictable…,.
36 grit would probably work fine too. The stuff cuts like butter. You could probably shape it with a bread knife and a handful of pumice.
Benny - if you haven’t tried it yet, you ought to shape a board with Extruded PS foam. I and a few others up here(Maine) have been using the big blue dock billets for blanks With a hot wire and some creativity you can cut three blanks from one billet. Billets go for around $55. You truly get 2 blanks and are left with a third blank that has very little rocker. Usually we just thow out the third, but it can be shaped it a low rocker board.
Although it may be a little more than $14 per blank the extra cost is very little and what you spend will be made up for in time saved. After you cut out your rocker profile you are left with an 8’ rockered rectangular piece of foam. You then cut it in half on the table saw and laminate the stringer between the two halves. If you want something wider than 20", just take two strips of foam board and lam it to the stringer between the dock foam. Cut out your board profile and go to town with your planer.
We’ve made over a dozen of these boards and they are all holding up pretty well. If you want more info drop me a line and I’ll explain in more detail.
More questions - Do you have pics of the finished board? Why the EPS and not XPS? Did you try to find the DOW Foamular product (Pink Panther)? It seems denser than the EPS and has a compressive strength of 25 psi. Did you consider shaping with hot wire method? What resin did you use - epoxy?
Sorry to be so nosy, but I’ve been edging toward building my own board and still haven’t decided on the final construction. I like Jensen’s Hollow wood boards but they might be at the edge of my abilities and limited tool access. I like the insulation foam method but haven’t been able to locate the XPS. Lately, there have been posts on the “external stringer” that caught my attention. That seems like a good compromise between the durability of the hollow wood board and ease of construction of foam. Any thoughts?
hsh- I like the idea. I have nothing against spending a little more $$. I’ll see if I can find some local XPS.
BillyBob & hsh - a lot of my motivation in using this material was sort of ecological. At least as responsible as you can get with a non-wooden surfboard. I wanted something non-toxic, recyclable, cheap, and that did not require additional transportation to get to me (Bay Area). Just as I bought the foam at Home Depot, I bought the epoxy, hardener, and cloth at Tap Plastics. The resins worked fine, although they stay open a little long for my taste. I used the Medium hardener because its supposed to cure the clearest & most flexible. I do wish it kicked a little faster, as I had to keep working it to avoid drips & runs. I squeeged with rubber & finished up with disposable foam brushes. I used 3x8 oz on the deck& 2 x 8 oz on the bottom. I also threw in a 16" chunk of 10 oz volan I had in the garage where I knee paddle. Even with all that glass, it can’t weigh more than 14 or 15 lb.
I also was shooting for something that looked garage. I didn’t even gloss coat the thing. Part of the idea & part of the charm to me is that its imperfect. I was lucky enough to get a chance to show it to Greg Hunt who made me feel great with comments like, “its so punk rock…I want one”. Coming from him, that was fun.
I am new to this forum, and was doing a search. Have read and re-read your post, and was thinking of trying your $14 blank idea. Never shaped a board though, in fact still a beginner surfer. the whole shaping thing really intrigues me though, and was wondering what the next seps would be after shaping it and gluing in the stringer and all. It’s probably complicated, but was hoping you could point me in the right directions as you seem to know how to do this. what else do i need as far as glassing/fins? thanks in advance.
Very much agree with you on the ecological side of things. That is why we started this project. I say, “We”, one of my cohorts was the mastermind behind the whole thing but has since been overwhelmed with renovating his house and has left me to charge forward.
We are able to get all materials locally. The only thing that I mail order are the fins, and my resin comes from Progressive Epoxy in New Hampshire. They make a great product by the way. We even tried using different than glass. The first alternate to glass was burlap. It broke after about 6 sessions - too bad to as it was a kickin’ shape.
We buy the billets at a local home building supply store. Try a store near a place where people have lakeside homes and need dock supplies.
They aren’t available at the Depot.
If you get serious about trying it I’ll email you a picture of the table we use to cut the rocker profile.
Chris, cool, thanks…we’ve got some dock type supply places around here. I know there are lots of places to find foam of all different kinds. I also like the hotwire cutter. I saw an easy ‘garage’ one somewhere online made with stripped wire & a car battery. That’s just my style. I also talked with Greg who’s used all kinds of cloth for laminating, including toilet paper!! If you see a board laminated with old blue jeans from Goodwill, that’s either his or mine.
little waves, you can read all kinds of information on glassing a board in these here Swaylocks archives. If you go with the white bead foam, just make sure you use epoxy resin & hardener, not poly resin & styrene catalyst. I got my finbox from Bob Miller’s shop for $6. Ask your local shaper for one, he’ll be cool. I also watched a local glasser do a couple laminations because its much easier to figure it out live than on a dvd or the internet.
The other cool thing about making a funky board that looks like it was knocked together in a backyard is that no shaper is going to see you as a threat. So instead of being cold or defensive, they’re stoked for you & encouraging. Its a much nicer world that way…
Benny,I had heard that some kind of sealer should be used like plaster and latex paint so the pores wont suck up so much epoxy? And also I heard there is some kind of problem with gases heating and de-laminating the glass?
I have made 2 xtr boards (lowes blue) both have delam problems.To bad to cause the fish is awsome.So anyways I was thinking about using the expanded foam. Thanks
Yep, lots of people seal the blanks so they don’t soak up lots of resin. I’ve variously heard about acrylic paint, lightweight diluted spackle, catalyzed epoxy resin without glass, latex paint…I didn’t use any of those.
The blank is so light, I didn’t care if it soaked up some extra resin. And the open time is so long, I could have even mixed a second batch during a single lamination if I had to. As it was, I needed 30 oz total (4:1 so 24 oz resin + 4 oz hardener) to wet out the bottom & wrap the rails and 35 oz for the deck. But I figured the spackle or whatever would add almost as much weight as the extra resin. I also thought that with a single laminating coat where all the resin that soaked in was chemically (not just mechanically) bonded with all that glass, I’d stand the best chance of avoiding delamination.
So far, so good. I’m 220 lb and knee-paddle a lot. I have really slight knee dents after the probably 12 hours I’ve spent on this board, but less than I’d have with a poly board with anything less than classic wt. foam & 10 oz volan. No heel dents at all.
A $14 dollar blank? That’s great- I’ve been thinking about shaping a board but i haven’t cause of the cost of blanks. But what is this about resin soaking into the blank? What do i need to know about this for shaping a board- I’ve never thought about that issue before.
I also got pm's from rfd with a really cool idea - put a horizontal resin & glass stringer between the panels and use that to 'glue' in the rocker (with weights as it sets) and add strength. I might try that to make (lay?) an egg with the foam I have left...
Credit for the internal glass sandwich stringer goes to Greg Loehr.
Benny, outstanding job!
Shaping and glassing a foamie surfboard ain’t rocket science as perhaps some would have you believe. Stick with decent dimensions, fair the foam nicely, saturate the glass well, keep the sanding dust outta yer lungs, pray for surf.
Though I’ve hot wired cores in the past, using a planer on EPS works really well and is so much simpler, just need to push a tad slower than with polyU cores … Greg also turned me on to usng DAP Fast ‘n’ Final spackling to seal the finished core before laminating - works great, super light.
We set up a window fan to blow the fumes away from us and out of the garage where we worked. The fan worked well enough that you could just barely smell the burning foam.
And yes - the wire cutter we used is just like the one you mentioned. Nichrome wire, a battery charger, and a metal frame to keep the wire tight.