had some problems with lamming, left some bubbles. and had a few dry spots, which i cut out, reglassed, etc. i think the main problem was the foam absorbing the epoxy. I sealed with spackle, but i must have sanded it off in some spots. Next time i know to seal better, and i will use a cheater coat to speed things up.
first hotcoat was bubbly, and in some small areas, weave still came through.
in the process of sanding, filling dry spots, sanding again, cleaning, and “gloss coating” (more like 2nd HC).
Any inputs on 10.5" FU fin boxes in 2 lb eps (marko) blanks???
I have Q-cel but am not sure if i should use it as a filler. Shoould i cap my boxes with glass??? in addition to lining the hole in blank??\
Love the ironing board-stand idea! Nice work & thanks for the photos.
Questions: Is that a small Sears/Craftsman compressor I see on the floor? Looks like the oil-lube cast iron 3 gal/125 kit they’ve had on sale recently. How is noise level from that in your garage when it kicks in?
Well Brah-----------The ironing board is a classic! Something we will all remember the next time we are staying at a friends or a hotel at Waikiki and are trying to finish off a board before “Dawn Patrol”. Seriously though------------Dry spots are a result of the fact that you cannot contain enough resin in the small container you are using to thourghly saturate even a short board. Get a bigger container and catalyze more resin. The plastic yellow squeeges are good for the rails and a finish pass to dry(if necessary). Get yourself a blue or white resin squeege for a good even saturation.
mcding… i used more then enough epoxy, and left a little too much on the floor. I dont know if you are just jerkin my leg our wwhatev. the buckets are perfect for boards.
anyone have advice on the 10.5" box???
im kinda sweating that part. Im taking it to baja with me this winter, so i gotta make it solid. i plan on a through-stringer leash hole. figured thats my safest bet.
If you want some insurance, put in a balsa insert (make the insert with rounded edges with radius same as your favorite templating bit and then make a template so that you can rout the hole for it in the board). Install the balsa block with epoxy , pigment and milled glass/cabosil/microspheres. Sand the block flush, then put a glass patch over the balsa. Make another template for the finbox, and install it.
I have included balsa blocks for finboxes when I glue up blanks.
Let us know what you do, and I hope your gloss coat goes well after your finbox is done. Remember to heat your resin and/or thin it to get it to flow well. It can be horribly frustrating at first to get a good epoxy hot/gloss coat.
Let it soak. It will soak in in it’s own good time, and nothing short of heating it up before lamming will change that. Also, wash your hands before handling your board. Dirt and oil showed up on the rails. Soap and water are our allies.
as for the dry bits… all the tips already mentioned plus I would add that using a roller rather than a squegee will help against airbubbles in your resin. Epoxies generally like to soak into cloth so you don’t need to rub it in with a squegee, just roll it out and lightly roll excess to the rails. Long potlife means you can take your time to sort crinkles and bubbles under the cloth. I put the finbox in after the glassing before the final coat, rout the slot based on a template half a mm bigger than the box and fill the base of the cavity with glass bubble and chopped fiber filled resin, oh and i scar the foam deeply inside the box walls the get a good fill with the chopped strand. I then fasten the box with small ammount of the filled resin, about halfway, toavoid heating and melting the foam. The beauty of epoxy is that you can bond chemically to freshly gelled epoxy (when it is still a bit tacky) this means you can slowly fill the cavitty around the box and finish it by sanding it flush and then laying a final layer offiber over it to get a real flush finish.The filled resin will bond strongly to rough scarred foam and should be enough fora surfboard, I did this on two single fin logs and I have got some big fins (9 and 10 inchers). In the event you want an even stronger box, wood is a good liner but so is high density foam. Thats what used to be done on windsurfers and they take much more force on the fin than any surfboard does.
finished up the fin box install last night. It went pretty well, for a first. Had to cut out hole with razors/Gerber/exacto/dremel/snips(stringer) which took a while . I mixed up way to much epoxy, and ended up throwing more then half of it away. So that sucked.
I used RR epoxy w/ fast hardener. Mixed it up with chopped 6oz and q-cel. Made a pretty good slurry, and filled the hole up. Set the box in tape it down and waited. Not to much exotherm at all , (one thing i was worried about).
Im in the process of sanding it down… sooo ill get back to you guys
i mixed up with chopped fibers, so that is all the strength i should need. the epoxy is pretty strong, and i plan on capping the box with 2 layers of 6oz after i sand it flush. any one have 1st hand experience with this???
"I sealed with spackle, but i must have sanded it off in some spots. Next time i know to seal better, and i will use a cheater coat to speed things up. "
I was under the impression that you did not need to spackle the 1.9lb marko foam. Thats what they say. Anyone have any experience against that. Nice job by the way.
Basically some pretty horrible hearsay tales about guys blowing out a poorly installed boxes on bottom turns (and then loosing the fin, because it happened in deep water) scared me into a protocol of a minimum of two layers.
Even capping the box with one layer will be enough. 2 layers will look a little green.
When you grind off the finbox, don’t be afriad to lean on the grinder around the box a bit so you get through 99% of the hotcoat. That way, your cap lam will be fiber to fiber and the hotcoat over that will smooth it all out. Remember that sanding or grinding can re-melt epoxy, so keep the disc moving. I kind of take swipes at it, reaching away from me to put it down, pulling it towards me, and lifting at the end of the stroke. You see your progress with every pass and the epoxy never gets too hot.
I meant two extra layers in the hole in the foam the fin box goes in (see my little diagram.)
Things sound like they’re different with an epoxy build. But capping a box with a single layer, at least for a resin build would be sort of a band-aid.
But opinions differ.
Kevin
(Edit. 10/10/06. Added the picture and a bit of grammar. KC)
No, Kevin, I also would have put a couple layers under the box instead of the chopped glass. But its a little late for that now, and a cap will help.
Styropoxy boards will only very rarely have a single layer anywhere. So the patch under the lam is unnecessary, in most cases. But I usually put 2 pieces of cloth under the box and then a single cap over it as well. The cap will help stop it from ripping out, if an impact hits the front edge of the fin & the board is loose or the rider is not weighting it - that’s when you see boxes lifted out of the front of the hole. The cap will help against that. But plenty of other finbox failures are where the rider was heavy on the board & hit something…the back end of the box can easily be mashed up into the foam of the tail & separated from the glass. The layers underneath help prevent that kind of damage…
