Been following for a couple years but never posted.I Ihave only shaped one board for myself from advice gained on this site.
My first board, a cortez minimal, has taken a battering travelling and I thought I’d repair it properly.
I’ve used solarez for my bodges previously but I have scraps of fibreglass left over from shaping and I’ll buy some Epoxy and spackle etc.
I’ve ripped the damaged ‘coating’ off the board back to fibreglass and foam and it is dry finally. First pic shows one ding, second is with damaged material removed and then another ding in the third pic (there’s more too.)
I plan to remove all broken/loose material and then sand, fill, glass, then hot coat. Does this sound reasonable?
I’ll attach images of the most concerning damage spots.
First, fill, then sand. Otherwise, you can wind up sanding into the undamaged foam to make an odd shape and making more work for yourself.
Rather than spackle, I’d use ‘clear’ gorilla glue. It’s a water-catalysed urethane, dampen (don’t soak) the area to be filled with a sponge or something, put a very thin layer of glue on, there you go. Then sand gently, taking care to bring it down flush with the original foam and no more. Spackle is weak stuff, it doesn’t like flexing. It shrinks as it dries. Lovely stuff for drywall, not so great for surfboards.
I would glass a patch over the missing cloth, then sand so it’s all flush and smooth, then a patch that laps well ( an inch or better all around) onto the existing/original cloth, sand the edges. . That third photo, sand flush and glass over one time only: it’s filled, you’re good.
As well, I’d add opaque white pigment to the laminating epoxy, nice thing about opaque white is it doesn’t look funny if you do several layers, unlike other colors. And white boards seem to last longer.
Wet sand, if you’re not seeing glass fibers when that’s done then I’d just give it a clear hotcoat/hloss and polish, if you do, white pigment in your hotcoat, give it a healthy coat and polish.
The trick is in getting it smooth and nearly invisible. Careful sanding and patience.
The very first thing you should have done was to clean all that wax off before doing anything else. Now, you will have to remove it without getting any into the open ding area. Any wax residue in the repair will cause adhesion issues. Hard to tell from your pics, but I assume it is epoxy/styro construction. Stick with epoxy for all repairs. Poly will melt the foam and make a mess.
The very first thing you should have done was to clean all that wax off before doing anything else. Now, you will have to remove it without getting any into the open ding area. Any wax residue in the repair will cause adhesion issues. Hard to tell from your pics, but I assume it is epoxy/styro construction. Stick with epoxy for all repairs. Poly will melt the foam and make a mess.
What you want to watch out for is things in the mix that are similar. Like the styrene monomer that’s used as a thinner in polyester resin which in turn makes styrene foam into marshmallow fluff by busting apart the polymers… Now, polyurethane foam when it’s going off, I think it gives off CO2 and such, but nothing that will eat styrene polymers. The MSDS is your friend here, as is the Handbook of Chemistry and Physics. Look for solubilities in the latter.
Interestingly, gasoline does a number on styrene foam, though it takes a while. Had a gas leak in a boat that used styrofoam, the blue stuff, as floatation. Anyhow-
I’m pretty sure the board was originally painted, again, compatibility, look and see what the ingredients are in your paint. Tha manufacturers website will have that. And epoxy is pretty inert. As long as it’s sanded smooth enough so the paint covers it up, all fine. Then, a decent clear coat over all and it doesn’t have to be epoxy, decent automotive stuff will be fine.
Have repaired 100’s of boards constructed in this manner. EPS/Epoxy. Make a filler out of Epoxy resin and Q-cell. Make it thick so that it can be spread and forced into the hole/divot with a plastic squeegee. Fill the hole, spread/squeege the filler. Let it harden and then sand flush. Put a piece of 6 oz or a couple of 4oz with epoxy resin over the ding. Do a filler coat of Epoxy resin with additive F. Sand the repair and fair it in to the surrounding surface. If there are any pinholes, use one part body filer and a hard plastic squeege to fill. Sand flush again. Prime with a white spray primer. I use “Painters Choice” which is purchased at ACE or Home Depot. Finish by painting with a white spray can of the same brand. After it is completely dry feather in with Wet N Dry sandpaper using water. If desired top with a coat of clear.
Thanks McDing! That’s the sort of repair I had in mind.
I’ve also got stringer cracking along the length of the stringer, I’ll post a photo once I remove the wax. Should I sand the cracking down, through the glass and repatch the stringer all the way along the cracked areas?
Board is probably stringerless, but would like to see a pic of what you are referring to. I sometimes grate or coarse sand some EPS foam granules to add to my Epoxy Resin/ Q-cel slurry. Cuts down on weight and creates more bulk for larger and deeper holes. For linear cracks; sand a 3 or 4 inch wide area the length of the crack. Cut a strip of 4oz and overlay the crack using Epoxy Resin. Fill coat and sand. Prime and paint. Feather it with Wet and dry using water. What you are calling a stringer may be a Veneer inlay(or overlay).
From an old alder product guide (Alder make the pop out boards under cortez name) it says:
“The surfboard is an epoxy construction with a composite stringer”
I’ll get the wax off and show you the cracking shortly.
It’s all the same on those boards. Sand and feather back the paint and glass, fill and sand. Put a piece of 4 oz over the sanded repair, filler coat and sand smooth to 220, prime with white primer, sand and paint. Wet sand if necessary to feather in the paint and smooth dust. Same basic process for any cracks down the stringer. Just don’t open ip the crack and put a piece of 4 oz over it minus the primer and paint. It’s all very basic stuff.
