I’ve been reading these forums for some time now - this is an awesome board. I moved to Hawaii recently, took up SUP and surfing as a hobby, and I am getting into board repair - also as a hobby. When I first got into this, I bought an old windsurf board (which as far as I can tell is a Hifly 300 CS) which had started to be converted to a SUP. I epoxied in some fin boxes on the underside and I can catch waves on it decently now. But I slip around on the top, so I am working on putting on a deck pad. I removed all the heavy toe strap screws, and I filled in the middle opening (for the middle skeg) with foam/gorilla glue (on top) and a thick layer of foam/qcell on the bottom. You can see the picture below. My question is – do I need to glass over the foam before putting on the pieces of 3M EWA deck pad to keep it watertight, or is that not necessary?
Note: I uploaded a few pics and going downstairs to take some more of the top and the deck pad pieces.
The last picture shows the EWA scraps I bought to make a deckpad. My intention is to cover everything that is foamed in with this material – just don’t know if I need to glass over the foam first to ensure it is water-tight - or if the EWA will do that. They are peel& stick 3M type EWA pad pieces.
ive done this conversion before with a windsurfing board as an extra paddleboard for my sailing school.
I did what you looked to have done. I took a long router bit and routed out the centerboard hole, foot strap mount holes, leash cups, all that. Made some foam plugs out of the same EPS foam the board was made of, put a 10oz filler piece in the hole with the plugs, sanded them all flat. Around the plugs i used a die-grinder with 80 grit and roughed up the surface. Weird stuff, it was like this non slip plastic amout 1/8" thick all over the board. Anyways, over each plug i put one patch the same size of the plug, a slightly larger patch, and then an even large patch, layed up in that order. Let em all dry and sand them flat, apply your deck pad however you want.
EDIT: re-read your OP. I added my patches for strength, and for watertight-ness. With that many pieces of exposed foam i would put patches over them 2-3 layers of maybe a 6oz E glass. Removing all that material i would imagine weakens the board, adding the foam fills the gaps and fiberlgass & resin make it strong again. Just my opinion though. Maybe those EVA mats by 3M are good and strong. test a piece under your faucet and see it its waterproof maybe. If all that fiberglass turns you off, just a light layer of 2oz over the top or even just plain epoxy brushed over the top will seal it really well.
Those repairs look good! But i have a question, why is the epoxy/poly all yellow?
Yes this thing is made of polypropeline plastic - quite thick. I have not yet gotten any leaks - but it is a pita to carry. I’ll probably cover it with one or 2 layers glass - but the good news is that even if the water gets into any of the areas that I’ve filled with foam - it still won’t get into the main body of the board - since each of the compartments I’m filling can also be exposed to water on their own (and have). But … the goal is to keep them dry.
Angus - to answer your question - everything is yellow because that is actually Gorilla Glue - dried. I was reading on this forum regarding the wonders of Gorilla Glue - and apparently the stuff that dries yellow (easily available in the store) – is the best for working on boards. There is another kind that dries white - and if this wouldn’t be covered up – I might have wanted to use white Gorilla Glue. I use Gorilla glue when I am just working gluing foam together and to the other parts of the board - that way I don’t have to mix up the epoxy resin and get all stressed setting it before it dries.
You mentioned polypropylene. I use polypropylene as a mold material for epoxy that does not require a release agent. You might want to test a patch to see if your resin will stick or release from the hull. I hope your project is a success, -J
In order to glass on Polypropylene you will need a specialized epoxy
West Systems has a product called g/flex that works on a variety of plastics. I have used it to repair a couple of Kayaks One had the bow broken off when a wind took it off a car rack before it was tied down. It dropped off an seawall hitting a concrete slab about 12 feet down right on the nose. I did that repair about 2 years ago and it is still holding up.
Hey guys - thanks!! You are right - when I was using epoxy and qcell to insert the fin boxes - it really did not stick to the surface. I had to rely on the fact that the finbox was also being epoxied (beneath the surface) to the foam below. I’ll check out those products.
Wow, I can’t believe it has been this long since I posted my questions earlier! So… in the meantime, I have finished filling all the holes with foam, and then glassed over any/all areas that had exposed foam with the only glass I had which is 6" (not 4") - i.e. the heavier glass. I also bought and glassed in a carrying handle. And… bought and glassed in a leash plug in the back. Then I spray painted the top everywhere with Rustoleum White paint + primer, which is what they recommended at West Marine. While at West Marine, I also picked up the g-flex. Since the glass on the top will be covered with EVA foam, I didn’t worry about using g-flex on the top - just did regular glassing with my Fiberglass Hawaii Epoxy 2:1 mix (and paint after that). I’ve cut the pieces of EVA foam out, but have not glued them on. I’ll need to use the G-flex on the bottom to re-glass (or glass over) what I had done before, since it really is not sticking well to the propelyne and it does indeed (slowly) start to come off in the water (did 2 test runs).
So in my test runs, here are my likes and dislikes:
love the handle. It is now only a 1-person job to carry this beast. Heavy, but do-able.
The board feels nice and firm in the center, where all the holes used to be and it is all solid and patched.
Having a real leash plug is awesome instead of what I used to do before - screw down the end of the leash to the last screw-in area for the former feet-hooks (which was too far foward from the end of the board anyway.
I love having a clean white board without holes / duck tape, plastic pieces everywhere.
It still has a flex-y feeling when on the water and a wave ( I was worried that would go away).
And here are the negatives:
I was hoping that even though my present repairs were not on the finbox (I had installed a new finbox a few months ago) - that somehow the board would no longer want to go right. Wrong - it still wants to go right. Its enough that for strong waves I have to keep my paddle in the water as the wave hits me, so that I don’t get thrown off as the board careens right. The finbox looks straight - people I have talked to say maybe there is a bend or kink in the board itself. I also need a bigger fin, although that may make it worse.
I still slip around on the deck (esp when not wearing water shoes) - so I need to put my eva padding down. I’m delaying that because I am too perfectionistic - I don’t want to just slap it on - but I need to do that soon. It may help on 1).
biggest issue - I could SWEAR that this board now sits in the water a little bit lower now. To the point where there seems to always be some water always flowing on / or around the board itself. Hmm. Now in the last few months I’ve gained 5 lbs unexpectedly, but I wonder if the board itself got heavier with that foam and glass. I put a combination of “beer cooler” foam (very light, eg from the foam my gas BBQ came in) and PU foam ( from a broken sufboard from Waimea Bay). It seems all that gorilla glue and epoxy (and glass) added some weight too - even though in the center I chiselled out two holes for the former mast plugs, which were filled with hard spray-foam crap - and put in light foam. When I went to the timed trial racing/upwind event locally the instructors said my old windsurfer was the right shape, length, and width, but if it just had more volume, that would be what I really need. Other people stood higher out of the water since their boards were thicker. But… can I add volume? I don’t think I can really “add” volume, right? If I created a raised nose/front area (because I’ll never walk the nose) and filled it with light foam, would that add volume and therefore float the board higher/better? Wow, what about when I add the EVA padding, that is going to add weight too!
I guess it’s great to be learning how all these things work… My friends tell me to just quit, call it a day, and buy a real board. But I don’t have the 1.5-3k to buy a real SUP board… and … I have 2 other SUPS I am repairing ( a 11" NSP and a 36" Surftech - those are both surf-sup boards - not good for flatwater or downwind). Any / all thoughts welcome on how I can make the most of this board stilll…
I’ll take some pictures of the current state of this board in the morning…
I don’t think the windsurfer (planing craft) is going to have enough volume to be a flatwater SUP (foam mini-rowboat). It would need extraordinary volume, which is contrary to your report of the board being low in the water. Maybe make a regular surfboard out of it? Sounds like you have some fun projects in the wings. All the best, J
After filling the middle with foam and glassing on the top and bottom, I put the EWA deck pad on, and yes it sits a little lower in the water, but works just fine still. Its fine for exploring, touring, getting from place to place, taking the dog for a SUP ride, and being stable in the middle of chop. I tried catching small waves on it but I slow down after getting on the wave - I think the drag from the 2nd read finbox is a problem, and I need to smoothen (sand) the board on the underside. But for now, I am considering this board “done”
