Coating a Front Wing and Stabilizer

[watercamper]

Nak: Thanks. I went over to the SolarEZ site. They had a couple of epoxy possibilities so I shot them an email to see what they would recommend. The one I liked was a bit pricey at $30 for 4 oz. Greenlight Surf Supply has another one that I like for $15 for 6 oz.

[OzBungy]

I use West resins for major repairs and PC epoxy pastes for chips and scratches.

All my foils are painted. I do repaints using Dulux Duramax spray cans. They're cheap, quick to dry and sands nicely. I think it's a urethane paint. Rustoleum does something similar.

For repairs I sand the paint off so it doesn't matter what the paint is. It's actually easier to see what you're sanding when you have coloured paint.

I can get a pristine white finish on my most used foil but lately I've gone for the mongrel look with black showing through. It's a lot less work and the end result is the same. From time to time I give the whole thing a scrub with Scotchbrite scourer.

[downunder]

Did that on Moses 633.

It was scratched like hell, with deep ones too.

The trick is to use a lot of masking tape. Or risk thick epoxy on TE or spillage everywhere on the other wing side. Top side, that is.

Then, because the epoxy surface tension is high, use a vaccum peel fabric. The fabric must be wet. After curing, the fabric goes off and even tiny dings are filled.

If not using a cloth, epoxy will just form to a surface, leaving it uneven. Small dings wont be filled. Bigger ones absolutely wont.

Thick epoxy wont go in tiny dings. Thin epoxy is a must.
After that, sprayed 2 part Ultrashine black marine type PU. Thinned with 30% thinner. Costly but great.

Good luck

[watercamper]

So I coated my wings with a coat of epoxy. It didn't turn out like I was expecting. I got a lot of fisheyes? Places where the coat seemed to pull apart a leave a gap. Also lots of pinholes? Small holes with not much resin. Here was my method. Let me know what I did wrong.

Prior to sanding, I used a wax remover recommended by SolarEZ, the company that I bought the resin from. This: https://www.solarez.com/product/solarez ... eaner-4oz/

I thought the wax remover left a film so I used Isopropyl alcohol to clean the surface of the oily feel.

I then sanded with 220 grit. Vacuumed and cleaned again with alcohol. Then a light swipe with a tack cloth. I was careful here to not press the cloth onto the surface so that none of the mixture in the cloth would get on the wings.

I mixed up the resin recommended by SolarEZ. This: https://www.solarez.com/product/wahoo-2-part-epoxy-kit/ (note; this is a 2 part epoxy, not a UV cure)

It did not spread like what I see on the Youtube videos. Easy to spread. Maybe I didn't use enough. I didn't have much extra. It wasn't dripping off. They said it was low viscosity but I wonder? It was fairly thick to brush on.

I've read about various things that maybe I did wrong. Surface prep was too fine using the 220. I didn't use enough epoxy. But to me, the epoxy was too thick for easy brushing. But maybe that's the norm with epoxy. I haven't glassed anything since the polyester days back in the early 90s.

I've used 120 grit wet to get the surface back to a uniform look. But I had to sand the new layer off in many places. My whole thought process was to get a nice barrier layer of epoxy on the wing to protect the underlying fabric.

[Nak]

I've had tack cloths cause these problems with other finishes. Also, alcohol can take a long time to actually dry, as in hours. If the surface is porous at all it can take longer. If you're re-purposing cloth from a household source, like sheets, there can be contaminants in the cloth that will cause issues. Dryer sheets are notorious for leaving residue behind that is difficult to impossible to fully remove. Get your rags from a good auto paint store. Sanding before using the wax remover can embed particles of wax in the surface. Always wax remove first, then sand, then wax remove again. Don't use cheap sandpaper. Use a quality sandpaper designed for automotive body work. Cheap sandpaper can leave residue behind. Make sure and remove all of the old finish.

Any time I'm trying a new finishing technique, I always try it on some test object first. Ideally, it's as close to what I'm finishing as possible. Get it right first on something you can throw away.

[Nelis]

Just last week I did a refurb on my wings.

I did not go the epoxy route because filling up scratches and imperfections is not a load bearing or sealing functionality. Dealing with epoxy is quite a bit harder, and high risk of imperfections (fish eyes etc) as you now have experienced.

I did a full spray with spraycan filler. This has a good contrasting colour too; so you're able to 'find' the exact shape of your wing again. Also, if you f*ck up, some paint thinner will strip it right off so no real harm done. It sand back nicely with 600 grit.

[watercamper]

Just last week I did a refurb on my wings.

I did not go the epoxy route because filling up scratches and imperfections is not a load bearing or sealing functionality. Dealing with epoxy is quite a bit harder, and high risk of imperfections (fish eyes etc) as you now have experienced.

I did a full spray with spraycan filler. This has a good contrasting colour too; so you're able to 'find' the exact shape of your wing again. Also, if you f*ck up, some paint thinner will strip it right off so no real harm done. It sand back nicely with 600 grit.

Wing tune2.JPGWing tune1.JPGWing tune3.JPG

Did you topcoat the wing afterwards? The spray putty, AFAIK, is basically a primer. Or maybe I'm wrong. Easy to apply. Dries fast. Easy to sand.

[watercamper]

Round Two: I decided to give the epoxy another try. Success! No Fisheye. No Orange Peel. No Pinholes. I also coated the stabilizers this time. Here's what worked and what didn't. YMMV

Didn't work: I had already sanded the surface with 220 prior to getting the Wax Remover that I mentioned earlier. I used this remover, then Isopropyl alcohol. Then a light wipe with a tack cloth. I didn't mix much resin and tried to stretch it along. Bad outcome.

Worked: After wet sanding the badly finished epoxy with 120, letting it dry completely (of course), I used a lint free cloth and denatured alcohol and applied the resin. I mixed extra resin so I could just push it along the surface. I thought that maybe I "overworked" the resin previously. It looked so good that I decided to quickly do the stabilizers.

Worked: I had previously wet sanded the stabilizers with 220. I didn't use wax remover nor Isopropyl alcohol nor tack cloth. I just wiped with denatured alcohol. I didn't have much resin left so I experimented with brushing it on thin. No problem!

So, I can also guess that something in the Wax Remover, the Isopropyl alcohol or the tack cloth caused my problems.

I now have a nice thick layer of epoxy to protect the CF and I'll be doing some wet sanding. This is a surf foil and not built for speed. I think 600 or maybe 800 would be the max needed. Any opinions?

[Nelis]

Just last week I did a refurb on my wings.

I did not go the epoxy route because filling up scratches and imperfections is not a load bearing or sealing functionality. Dealing with epoxy is quite a bit harder, and high risk of imperfections (fish eyes etc) as you now have experienced.

I did a full spray with spraycan filler. This has a good contrasting colour too; so you're able to 'find' the exact shape of your wing again. Also, if you f*ck up, some paint thinner will strip it right off so no real harm done. It sand back nicely with 600 grit.

Wing tune2.JPGWing tune1.JPGWing tune3.JPG

Did you topcoat the wing afterwards? The spray putty, AFAIK, is basically a primer. Or maybe I'm wrong. Easy to apply. Dries fast. Easy to sand.

Yes it is just a primer indeed. But I didn't see e reason why that wouldn't be enough for what it is supposed to do? It's not protecting anything or needs to have a visually pleasing finish. Also right after I was done sanding the wing, it was friday afternoon and the wind picked up... Priorities

@Watercamper; opinions in this topic: viewtopic.php?f=196&t=2412541

[Nelis]

Hi, just to report back on my findings after 3 sessions since the refurb;

The effect is very noticeable in a positive way to me. The way the setup rides is much smoother. I ride in sea chop and waves exclusively and the same conditions now feel much smoother and sure footed. I'm quite sure it's a bit faster too, while being easier to control. Coming on the foil and stalling is softer too, when it's on the verge of lift-off, and speed lacks, the 'rodeo' is much less abrupt.

I did not do anything to the mast yet, but I will treat that as well. There were some instances in sharp turns or going upwind while going over the crest of a wave where ventilation would 'tackle' me. My theory is that the yaw angle between the water flow and direction of the mast is too big and the flow detaches, allowing for ventilation. I noticed on the beach after my latest session the wings were still evenly covered in a fluid film, where the mast was almost completely dry with some larger droplets (the latter being undesirable).