Still working from the same pair of 4’x8’x2" 1# EPS panels from Home Depot. This one’s a 8’0" mini-log with a bit of vee through the tail, a 1" redwood stringer, nose & tail blocks of Okume & Bass, all volan cloth and a really flexy glass-on fin. It’s not yet hotcoated, but looks pretty good so far. Except for the custom, asymetrical nose…
Once again, I glued the blank together and the stringer in with Elmer’s. This time, I roughed in the rocker with a big hot-wire bow cutter I made out of scrap pieces of wood, a steel wire, and a battery charger.
There’s been some questions about how well Elmer’s glue works with EPS foam. Specifically, people didn’t know if the glue would hold up when it isn’t exposed to air to cure. I did some break tests to see - both along the stringer on the piece I cut off the nose to install a nose block and with a scrap piece of foam & piece of block. I glued it, let it sit for a day or so, and then broke them apart. Both times, the foam failed about 1/4" away from the glue line. On the scrap & block piece, I didn’t glue the whole surface, just the end you can see with foam still stuck to it.
This is a photo of the hot wire bow. The top piece of wood is bolted through with a single bolt so it can swivel a little, and the back side of the bow has a tension spring I pulled from the belt pulley of a broken washing machine. The spring is to keep the wire taut as it stretches a little when it heats up. I found the right setting & wire combo is 22 ga stainless wire (24" span) and the battery charger set on 6V/10A. I wrapped the wire around screws with rubber insulating grommets and leads to 12 ga copper wire that the charger’s alligator clips hook to. Works great. Waaaaay less dust.
did you glue two of the two inch thick sheets on top of each other? Or is that just one sheet? If it is two, do the stick toghether well? I am going to start on my board in a week. I just have to glue my blank and make a list of the tools I need to borrow from the berkeley tool library (free of charge) which is awesome. I don’t have a hot wire cutter for the rocker. I was originally planning on glueing the rocker into the sheets by laying them on top of a board to duplicate the rocker. have you tried gluing? Does it work? I did notice that the 2 inch sheets are not quite as easy to bend as the 1.5 inch or 1 inch. How can I tell what density foam to get?
Was your fin a thin wood core, then with a couple of layers white tinted glass either side ? It’s an interesting effect …reminds me of the look of those [chinese takeaway food] ‘wontons’ ! [Hopefully a bit more rigid in the surf, though.]
I’ll be keen to hear how your mal rides. My 8’er is now a bit thinner than in the last lot of photos Hicksy grant took …about 3" on the rails now. It still needs to have the deck skinned, be re-templated a touch to true up the outline, thinned more, rails and bottom done. Yep, PLENTY of work ahead still ! [At least ‘Hicksy’ has some time off now. Just got to wait a few days for the 38 and 39 celsius [100 degrees fahrenheit on the old scale] days to go…and to save some money for the epoxy and cloth, tint , and finbox. At least I already have a couple of wood single fins ready for it…
The blank was made from 2 pieces of 2" EPS, glued flat with Elmers. I pre-cut the stringer for rocker & thickness. Then I just split the blank lengthwise and glued in the stringer - again with Elmer’s - bending the blank for rocker along the stringer. Even glued to 4" thick, it bends fine.
The board’s fun frontside, not so good backside. Too much vee, Wp is +4", fin is too flexy. Its also a little heavy. My first EPS board came out a little soft with 6+6 glassing, so I went 10+10 on this one. Its hard, for sure, but too heavy. I also did, all with epoxy, both hotcoat to fill the weave and glosscoat for final sanding. Probably only needed the hotcoat and should have sanded more on that.
Yeah, Chip, the fin is plywood core, foiled, and glassed with 2 layers of 10 oz with white tint. Then I glassed it on with rope & a 6 oz layer that went almost all the way up. The foil is good and the flex is what I want, but it might be (8.5") a little too much fin for the board.
The lam is from a graffitti at a spot I surf a lot. A friend took a digital photo, I printed it on rice paper (I got the roll kind from Michael’s and cut it to 8.5x11 to fit my printer) and lammed it in beetwen the 2 layers of 10 oz.
nice work looks fun. this should probably be another thread but I’ll try this. I completly butured my first atemt with a clark 9 8 and ay a 100 dls. a pop thought I should try a home blown eps for th next go round. can anyone expound on the hotwire cutter… sorry if this was the wrong thread. again the board looks killetr. reguards Greg
Faded, I don’t seal these blanks at all. They suck in just a little more resin that way, but they also bond much better and look cleaner. I tried lams on scrap pieces of foam, with both spackle & nothing. The spackle one, the glass & resin peeled off as easy as a banana. The unsealed one took off 1/4" of foam with the lam. I didn’t try mircoballoons.
I tried guitar string for my wire cutter, but it broke. Plain stainless steel wire works fine. I power it with a car battery charger, 6V/10A setting, no transformer needed.
