Took my two panels (2" thick and 1" thick) of dow/corning pink xps foam out and set up a caveman style glue press to glue in some rocker. A flat bench with a 5" pile of 2x4’s at one end (nose) and a 3" pile at the other. Spread out a lot of Elmers on the panels and weighted the foam down with everything heavy I could find - cinderblocks, bags of cement, heavy power tools, cans of paint, scrap lumber. Left it alone from Friday PM to Sunday PM. Took off the weights and had a stringerless, rockered, pink, 3" x 24" x 8’ rectangular blank. I spent at least an hour milling from the bottom to achive some foil in the nose (and tail) and take about 1/2" out of the over-all thickness. I templated a 7’6" x 13" x 21" x 13" rounded pin with the wide point 3" back. and cut it out. So far, so good. Then I spent about another hour working on the deck and top of the rails. Noted that at places along the rail, where the glue seam is, there is still some squeeze-out of un-cured Elmers (though there must be enough that dried since the rocker is holding up fine). Note to self… Maybe use epoxy for the glue-up if there is a next time. I need to finish off the bottom and rails and final blend/sand the whole thing. Pink xps shapes well. It does not plane as fine as the poly clark blanks I’ve worked on but it sands out smooth enough. To work on a non-foiled blank is very time-consuming. Then again this blank would cost about $20 - including the glue - if you bought the foam at Home Depot. For the bottom - I’m thinking a little belly in the first 1/3, into a flat or light concave in the middle, into a light V in the tail. Tucked under edges in the rear 1/3, the rest soft. Single fin - long FU box (maybe Future boxes for side-bites or an optional Tri set-up. attempting to give myself alot of options w/fins). how’s that sound? Eric J
Hello Eric, sounds good for $20. Hopefully someone else will comment on your bottom contours but for what its worth here are my comments. Belly or V in the nose will help the board cut thru chop and texture. A single concave in the mid point will flatten the rocker in the stringer line while retaining the curve in the rails. The lowered rocker in the stringer will give the board good on edge speed but a concave surface reacts badly to chop on powerful waves, my single concave shortboard does cope with weak windswell chop fine though. However the fun gun dimensions of your board will help compensate and stabilise the wild ride of a concave in heavy chop. If you do want a lot of stability in heavy chop then a double concave placed in a V works better (I have a mid length board with this configuration). If you are going to set it up with tri fin options then how about you post the placements of your side fins for everyone to comment on. I already posted the fin placements of my 7’ 4" gun under Mike Fairbanks pin v squash thread.
Mr.J - I’ve yet to map out the position the fins but I figured a standard Thruster set-up for the sides with a long fu box in the center so that I can use it as a single, thruster (I need to find a good center fin for this), or 2+1, set-up. - I’ll take a look at your post (and the archive) when I get to that too for more ref than my old tri-fin provides. Thanks for your explanation of the bottom contours. I’m in generally choppy EC surf (LI, NY) though we can get some days w/more size and power. But I’d be mostly out in ‘average’ waves. I was thinking that the belly/concave idea might work here since there is often chop and not tons of power. If I can work the concave in, great. if not I’ll go with a flat mid to a light v-panel in the tail. Nothing fancy. I rode a single fin rounded pin a long ways back and liked the smooth feeling. Just hoping to get to somthing kinda like that. Eric
What is the difference between the blue board and the pink board?
Joe, I’m not sure of that, someone who knows more about either insulation (Shine - I think…?) or the foam making process’ (Greg L.) might know. The most basic difference to me is that the Pink foam needs to be colored over - I don’t want a pink board! - If I had had access to the blue foam I probably would have used that instead. The pink is just a little tough and rubbery for the power planer and surform, bigger bits come out than on a Clark blank when planed, and the surform chunks it up a bit too. Requires more sanding than a Clark blank. If anyone has used the blue insulation foam for boards… how does it shape? Eri J
on the subject of blue xps I scored a 8’ x 2’ x 5" block in silicon valley last week. I would have been happy to use pink if I could find it and if I was serious maybe try and get some EDRO sent up from J-H Pro in Oceanside but needed to get started quickly. So I found some Spyder foam locally. This stuff has a compression resisting grain but is expensive - $98. I stretched the rocker measurements given in Clark’s catolog for their 6’ modern fish blank to 6’ 6". Marked these measurements on some masonite and by placing nails either side of a flexible plastic batten (1/4 round window moulding from homedepot) created a rocker template. I didn’t scale up the rocker measurements to attempt to produce a reduced curve from the shorter Clark blank. I put a slight staged extra bend in front of the fins. One of the objectives of this excercise is to help me understand rocker. I was able to single handedly hot wire cut a blank using 2 of these templates nailed to the side of the foam block. the power source was a tekoa hobbies unit which I’ll probably be selling soon. The wire I used was made for this and mounted on a home-made bow. This wire does not require fan cooling as Greg L recommends for other types of wire. Using curves from an ellipse I drew out a 6’ 6" x 21 3/4", 16 N, 14 3/4 T. The rounded pin shape with those measurements are rather blobby. I don’t expect this to be a great board but this is what I wanted. So why didn’t I widen the tail dump a swallow on it to make a traditional fish or narrow the mid point to produce a more conventional shape? the reason is I’m hoping to see the impact of such width and whether I can control it with longboard style belly ending in panel V. I’ve attempted to create some of the features of my very nice Takayama min-tank in a shorter board. I’ve placed quite thin, low radius soft down rails to test the theory that such a rail holds a nice high line and may compensate for the rounded outline. the tail has been kept on the narrow side so that I can build on my experience with twin fins during the era when Mark Richards and Martin Potter ruled (ie narrow tailed twinnies not fishes). I found tails of about 14 1/2 worked ok with fins 10 1/2 - 10 3/4 up from tail. These boards were acrobatic and could be sent into tight drifting cutbacks and although I’ve never ridden the Steve Lis style fish I’ve heard that they are more down the line and tracky. back in the late 70s and early 80s i was riding sub 6’ boards, I’m now older hence the extra length. I’ve finished shaping it and am now in the process of embedding 5 future fin boxes. I want to find out what a twinzer is like and whether having multiple fin sets trailing each other will help give the blob some direction. Sliding boxes would have been nice but I have limited time so got some epoxy, glass and futures all delivered in one package from fiberglasssupply.com. I think I’ll know if the twin fin setup feels too far back. If it does then I can put longboard side fins in the front boxes and try a pair of smaller thruster fins in the rear pair. If however the fins feel too far forward then a smaller fish trailer fin can be put in the 5th tail box. Like you Eric I want to play around with fin configurations to discover how they work. I do however expect this board to catch waves well - its quite thick at 3" with a lot of dome in the deck hiding the thickness. I’m also hoping it will trim quite well with its flat rocker. It is intended for onshore windswell. PS Eric regarding your idea of incorporating a single concave in your board sounds worth trying as you do have some compensating design features and sounds like you are aiming for speed extraction rather than control and stability. if we don’t try our theories we will never find out! comments on my design anyone?
Experimenting can be fun. Hope that little thing flys… How is the blue foam to shape? Eric
Also - Mr. J. - I’d be interested in knowing what epoxy you got and how that works out when laminating. Best, Eric
I don’t have any pink to compare it with but the spyder foam(supposedly a hi strength xps) would rip under a surform tool and I didn’t use that tool at all. If the electric planer was moved at what I would consider normal Clark shaping speed it would rip also, but fine if I went slowly. The planer was rented from homedepot and I suspect it didn’t have very sharp blades coz I’ve successfully shaped eps before with a regular planer and that stuff is more fragile. Maybe the barrel replacement for the blades is the way to go for xps? I did the initial hack of each rail bands with the handsaw that did the outline. I did this simply to reduce planer dust. The sight of an amateur hacking away at rail bands with a hand saw might horrify a professional, but when smoothed out with long passes of the planer an even result was produced. Spyder foam does however sand very easily with a wooden board with a layer of wetsuit rubber and sandpaper glued to it. I was able to put the bottom tuck of the rails in easily with this block. Finishing rails with the mesh (drywall sanding screen in my case) worked well too. All the dome in the deck and V on the bottom were put in with the planer before being smoothed out with the block.
by resting the casing of a dremel tool on a block of wood of suitable thickness I was able to use the wood as a guide to freehand rout the fin box slots. the dremel tool was fitted with a little sanding barrel. Future boxes are very easy to use 
by stacking some more wooden guides I could get the dremel tool to do the recessed part for the box flanges too. the epoxy I have is SB112. At this stage all I can say is that it does set. I measured 2oz of part A to 0.9 oz of part B on my electronic kitchen scales. After about 20mins the surplus in the mixing pot was warm but still liquid. I decided to go to the office at this point and left it. Its lunchtime now and and I returned to find the resin has set. I think most home builders experience the apprehension of waiting for their first batch of an unknown resin to set, so you can imagine that I’m feeling quite pleased now I believe this resin setting anticipation has led many home builders to add an extra bit of catalyst as a safety margin … I’m starting to ramble I wore a fume mask but there was no smell.
Mr.J Thanks for the info. sounds like the blue shapes just about like the pink does. Not optimum, but workable. And - it’s not pink, which is a plus to me. The grit barrel may be the way to go - or maybe the EDRO foam is much better than these (?) After you lam - please give some details about working with the SB-112 epoxy (expensive stuff!) - as compared to Poly. How much you used, free - or cut lap (how do you tell when to flip and cut the lap?), cure time, etc. I’m apprehensive about getting the epoxy mix just right - there is so much more ‘slop’ factor with poly cataylst and it would be really bad to have a board not cure because the mix was a bit off - as a newby to epoxy, that scares me. Eric
Hello Eric, I’ll keep posting reports of my blue xps/epoxy process. I’m interested to hear updates from how your pink project is going too. In fact your original pink xps thread is what got me to the point where I could contain myself no longer and set about satisfying my urge to build something. All your details about innovative use of bags of cement etc is interesting so I’ll attempt to maintain this level of detail.
when I did the 2/0.9oz mix I didn’t make it clear that I was using this for the 5 future fin boxes. I needed only about 2 thirds of this amount to put in the 5 boxes. Satisfied that my kitchen scales which measures in units of 0.1 of an ounce was producing a settable mix I decided to lam the hull this morning. Despite reading the thread about reverse laps its been many years since I last glassed and the flat underneath looked like it would lose less resin to the floor than the domed deck. the 32 oz yoghurt containers that I had been washing in the dishwasher and storing for no good reason now come in handy for the mix. I measure d 8 oz of part A to 3.5oz of part B. The strategy I had planned was designed to get me a high probability of success but not necessarily a good or efficient way of laminating. By mixing less than I needed I figured I could lam one side of the imaginary stringer, do another mix then lam the other side. I had spare mixing pots ready. I also lammed just 1 layer of 4oz S-glass in the belief that it would be much easier to push the epoxy thru just one layer. As it turned out that mix was enough - just. although I followed the strategy of saturating just one side and wrapping before attempting to saturate and wrap the other rail. Within 15-20 min the resin had changed from runny polyester consistency to a thicker treacle, however unlike poly it does not gel and just gets thicker - therefore does not turn into an emergency situation in 5 mins. The whole process was finished in 30min - some fiddling round the future boxes needed - I had cut slits to cope with the lip next to the slot which looked almost as hard as channels - any other suggestions on this? squeegee used was a cheap disposable from TAP plastics. To overcome the resin kick apprehension I stirred with a plastic spoon for 3 minutes. I had noted that when stirring non emulsified peanut butter, the oil and peanut paste combined much quicker when stirring with a spoon than a knife. I then went to the office to sit in my cubicle.
I was not able to come home lunchtime to check the lamination. The department I work for is closing down/going thru an aquisition and decided to have a barbequeue. This explains why I have had way too much time on my hands hanging out at swaylocks dreaming of surfboards. This situation won’t last forever so It also explains my need to build quickly with available materials rather than searching for the cheapest/perfect foam etc. I arrived home at 5pm to find all was well, the glass spikes on the laps were just a bit too soft to grind with my dremel tool and I couldn’t be bothered to cut them all with a knife. So I decided to put the next layer of 4oz on top of the semi cured lam on the hull. I figured that if 8/3.5 mix was needed on non sealed foam then less would be needed on top of a lam. So I did a 6/2.6oz mix this time. That was enough with a little to spare. I’ve been fairly concious to keep weight down so maybe if I flooded things a bit more I wouldn’t have so many little airbubbles. But never mind, I’m not too worried what it looks like and I haven’t botherede to do a spray job on the foam. One of the things about hot wire cutting a blank is that the spare top and bottom pieces make a nice rocker table. My blank has no stringer and therefore I don’t want it flexing during lamination. I narrowed the spare top piece to give me room to squeegee the laps and placed it on top of my ironing board. It was good to see the ironing board finally get some use as a laminating stand. Shaping was done by using the spare pieces on top of my computer table. I’m anticipating relocating shortly so its not worth me building a proper shaping stand. Anyway laminating went fairly smoothly and afterwards I sealed off the door of the room with masking tape and went in to the living area. I’ll be sleeping on my convertible futon/sofa tonight. As a bit of background information, I am building this board in the bedroom of my 1 bedroom apartment.
Building indoors and in an apartment! Oh man - I’ll never complain about my little dirty shed again! You are commited. (somebody lend this man a shaping room before he laminates his socks to the floor). You said you taped the door - for odor? how bad was the smell from epoxy? I’ve had the neighbors complain about poly smell when I’ve laminated in the shed so avoiding that is one of my reasons for an interest in epoxy. Good info on the lam amounts. That helps take the edge off of the price of epoxy. My plans are to color the foam with a layer of colored epoxy resin (foam stain) to cover the pink, then laminate clear - or maybe very lightly tinted - epoxy over that. I’m toying with the idea of a carbon fiber strip inlayed into the deck, like a faux stringer, to give a bit more stiffness and strength to the deck - like yours no stringer in this board. 3 layers of 6 on top and two on the bottom. I’m not too concerned with the weight going up - I ride a 6’6" twin that I built last year - classic foam and 2x6 over 1x6 and glossed - It weighs over 10 pounds (!) and I like the way is surfs. Otherwise I still need to gather the laminating materials so it’ll be some time before I get this board done. Next step for me is the filling of rough spots and dings with spackle, fine sanding the blank, then when the laminating stuff arrives - setting fin boxes, coloring, and lamination… and so on. Considering make a fin or two too. Best, Eric J
Hello Eric, I have already laminated my socks, but not to the floor. I’ve been wearing open sandals over them to do the glassing. This way I can easily step out of them and off the poly tarp and not get resin on the carpet. Masking tape on edges of bedroom door was to stop vapour. Although barely noticeable for future box installation, glassing the hull did produce a vapour. Not strong but didn’t smell healthy. Epoxy used to have a very bad reputation for being toxic, but from browsing swaylocks I get the impression it has shaken this off. I did wear a mask. Your neigbours won’t notice the smell. No complaints from mine so far. I waited until the occupant from the apartment below me had vacated before I did the shaping - the electric planer does scream. If anything they will get fed up with the incessant vacuum cleaning that I’m doing.
no glassing before work this morning. I’m instructed to be in my cubicle by 9am - sounds ominous. I find out that the aquisition is going ahead and that I’m wanted for another 6 months. I was hoping to get layed off and sent back to Australia, but this scenario is OK, America is a cool place. In fact it never ceases to amaze me with its business activity. For example consider plastic fabrication. This would normally be strictly a fringe or industrial activity anywhere in the world except here. I live near a trendy part of silicon valley that has this street full of restaurants and coffee shops where the geeks and entepreneurs hang out. Right in the middle of this street opposite the bookshop is a plastic fabrication retail outlet. Its got polyester surfboard resins, squeegees and all sorts of stuff. I found out that the disposable squeegees sold there can be re-used, just break off the set epoxy, but good to have at least 2 so that uninterrupted laminating can take place. Anyway I get to glass this evening. A bit warmer and I wonder if I will get a better result by doing two separate mixes. The deck today. The heavier 6oz s-glass will need more resin so I mix up a 6/2.7 oz mix to start with and laminate the left side of the board. I try to flood the resin on a bit more at the expense of losing some to the floor. I’m trying for less airbubbles today. I get the left rail and just over half of the deck done and then go and mix a 4/1.8 oz pot. The quantities are spot on but doing 2 mixes sort of disrupts my flow and the result is not much better. hmmm perhaps I should have got the glassing 101 video first, anyone know when the master glassing DVD is coming out? I’m satisfied though, I’m well on my way to getting a rideable board and I’m not fussy about the appearance. However I still have plenty of opportunity to mess up. Anyone willing to rent me their sanding bay and sander? I’m already pushing the envelope with what can be done in apartment and I’m still hoping to get my rent deposit back , so not planning on sanding in here. I could just take it to a factory, but doing it myself would be more fun and I could control how deep the sander goes. From what I remember I was a better sander than glasser.
went for a surf this morning. So late start to glassing today - the second layer of 6oz to go on the deck. Its starting to heat up in the valley by early afternoon but I’m sufficiently confident by now to aim for a single mix of 8/3.5 oz and just to see what its like push it thru 2 layers with a tail patch. As it turns out not quite enough resin. Although I’m getting better at this and was able to tip a greater initial quantity without spilling on the floor. No big deal to mix a bit extra. The tail patch looks a bit aerated so I use some of this second mix to baste it which does fill the bubbles. It seems at least part of the cause of my bubble riddled glass job is laminating too dry. My idea of sealing the blank with an initial laminate is sort of working in that the second laminate absorbs less resin, but maybe your plans for a foam stain will work better Eric. Or I should have sealed with something else first, or I should accept a heavier board and be more generous with the resin on the first layer of glass. I’ve also made the mistake of not grinding down the rough edges of the first lap well enough which introduced some bubbles where the deck and hull layers meet. Any advice/comments from anyone on what I am doing are welcome. At least with this method I do get twice as much practise at glassing this one board.
Hello Eric, it was my 6’ 2" single concave I used today. It went fine in side onshore semi windswell generated in the gulf of Alaska. This board was done for me by a professional shaper who surfs very well and had shaped some concave boards for himself. Off topic, but I’ve met some shapers who have lost interest in the act of going surfing, doesn’t mean they are bad shapers though. I’ve just measured the concave with a straight edge and it is no more than 3mm. This shaper believed that more concave would give too wild a ride in a heavily textured surface, but don’t let the stop you putting more in if you want to. The 6’ 6" twin you made, what are its vital statistics and how does it ride?
its sunday now and another surf this morning before resuming building. I’ve decided to be brave and hot coat the deck with polyester. The makers of sb112 say that polyester will stick over overnight cured unsanded woven texture glass job. Its been almost 24 hrs so I give a light sand and use the dremel tool to take off all the spikes and bits hanging down from the laps. I suppose an expert wouldn’t need to do this but I’m a messy glasser. I pigment the resin white. I know that sanding is going to produce a very patchy looking result but I’m planning on covering the whole lot up with coloured acrylic sealer. This way I can also get an appreciation as to how deep into the laminate I am sanding. Part of the rationale behind all this is the statement from the manufacturers that no epoxy, sb112 included is UV resistant. The hull has already had a couple of days of curing so I’ll put epoxy on that to avoid the risk of polyester peeling off. I mix up 12 oz of polyester. This is probably too much but its cheaper than epoxy and the multiple mix method isnt going to work as well for hot-coating as glassing. A few minutes into brushing the hot coat I get the horrible feeling that the laminate is absorbing it - in fact I’m convinced my pinhole riddled board is soaking it up. This is of course disastrous on a styrofoam blank. Dammit dammit dammit dammit dammit dammit dammit dammit - not the actual words I am repeating to myself, but you get the picture. I quickly brush the bare areas and then plonk two empty yoghurt carton mixing pots on my rocker table and rest the board wet resin side down on these in the hope that gravity will keep too much resin from eating the foam. Assessing the damage I’ve now got smudged rails where I handled the board to turn it over, I’ve abandonded the hoat coating without following the proper brush stroke sequence, probably will have two rings resembling coffee mug marks where the mixing pots are supporting. But worst of all there would be foam eaten cavities hidden behind the glass. When the resin has set I give it some pressure tests with my thumb on the pinholed areas which are inconclusive. More investigation is needed so I choose a bit of the tail which has some pinholes and use the dremel tool to cut away a disk of laminate into which the deck plug can fit. The fiberglass when peeled off doesn’t show any evidence of white polyester leaking, but I’m still convinced my laminate was absorbing resin. It certainly has pinholes. Why oh why did I have to be too experimental. I’ve already covered new ground (for myself) with xps and a home designed rocker which I single handedly hot wired, I should have gone the safer all epoxy route. I don’t know what condition the most polyester saturated parts of the deck is in. But I think I can still get a rideable board. Not sure how well it will resist water. Certainly don’t need any thermovents anyway. I’m not sure whether its worth trying to get it sanded properly now. Maybe just epoxy hot coat the underneath, do a rough sand job by hand and try surfing it.