The skegs on the Nacra need some love. They are not terrible but the flat spot is about 1/4 inch wide at the deepest part of the skegs. I have read here about glass tape and epoxy repair. My question is, tape over a flat will make a flat face, does that matter or should i rebuild a sharp edge, an inverted vee? Thanks.

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John

Nacra 5.0
CT
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i wouldn't use glass or epoxy to repair small flat spots
when i did my bottom job last year the only epoxy i mixed was to add additional material to the bottoms 1" from the transom/sterns because this is the only spot that had the gelcoat worn down to epoxy. I then used thickened gelcoat and fill any voids and build up some shape to match the surrounding area and fair to perfection (or close)

Can you get some images so others can give you more detailed suggestions?



Edited by MN3 on Apr 13, 2020 - 11:31 AM.

Yes, once the monsoon over the state of CT leaves.

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John

Nacra 5.0
CT
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I put an image in my folder titled nacra trailer.

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John

Nacra 5.0
CT
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If you don't have a compressor and need to do a small project, get a Preval sprayer.

https://preval.com/diy-pr…products/preval-sprayer/

X



Edited by MN3 on Apr 14, 2020 - 11:38 AM.

Once your repair is complete, take your stimulus check and buy a set of Cattrax. Future problem solved.

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Master UniRig Sailor
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Sounds like just a layer of West is the way to go.

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John

Nacra 5.0
CT
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ctcataman

Sounds like just a layer of West is the way to go.

really? Sounds like epoxy? cause i was the only one to give advice and i said i wouldn't use epoxy here

Its worn through the gel coat, and appears small gaps are present.

I guess i need to read about what gelcoat can do. All this epoxy/polyesyer resin/ gelcoat in new territory.

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John

Nacra 5.0
CT
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Well, IMHO I would certainly repair the hull the right way with fiberglass. Gelcoat should only be used to provide a somewhat durable finish on the surface of a fiber glass. You never said what kind of Nacra you are repairing, but if you can, use a contour tool on your hull and make a template out of thin plywood. Tape around the repair the area to protect from resin drips. Remove any lose glass in the repair area. Any type of sander with 40 grit can be used to do this, but I use a die grinder with a round diamond bit. Remember prep is everything when you paint and repair stuff. Pre-cut several strips of 10 oz fiberglass to cover the repair area. I cut the first a strips bigger, to overlap the repair by 1” – 2”, then gradually smaller to fill the area. Usually three to five strips of fiberglass are sufficient. Occasionally, more layers are required. You want the glass to be higher than the actual shape of the hull.
With the fiberglass 10 oz. cloth precut and ready for application, the repair area should be wiped clean using acetone. Be sure to have a disposable chip brush and a bubble roller nearby. Use vinyl ester resin, and using Methyl Ethyl Ketone Peroxide, catalyst the resin with 4 – 6 drops per liquid ounce. Apply the catalyzed resin to the fiberglass by brush, then use the roller to remove any air bubbles. Only use enough resin to saturate the cloth, excess resin should be removed. Once the resin has started to dry, but not full cured, use a Stanley Surform to shave/ shape the hull using the template as a guide. With the resin fully cured, sand the area. Use is a pneumatic “in-line” or a jitterbug sander, this smooths the bottom curvature without any high or low spots. Once shaped, add 3 – 4 drops of surfacing agent (wax) to the final coat of resin and apply a thin coat. Sand the last coat of resin using 220 grit, then re-check your work with a template to see if it’s back to factory specs. Use Formula 27 or Total Boat fairing compound to fill in small pin holes and light scratches to prep the hull for gelcoat.

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Kenny Boudreaux
2010 C2 F18 USA 323
Goodall Design "Southern Area Rep"
Owner of Sailboxes.com
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Kenny i certainly defer to your experience but may i ask why use glass?

if he has no damage and is worn down to the glass but not any further, is more or new glass needed?

Did you see the damage?
it looks very minimal





Edited by MN3 on Apr 20, 2020 - 01:56 PM.

I was thinking what was worn off is less than the size of a pencil.

MN3 thanks for getting the picture put here.

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John

Nacra 5.0
CT
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ctcataman

I was thinking what was worn off is less than the size of a pencil.

What does that mean?
width of a pencil?
depth?
lenght?

all that matters in my world is how much epoxy has been sanded off or damaged
it doesnt look like anything more than some very minor surface scratches on the exposed epoxy and that is why i say no new epoxy is needed

again i strongly defer to Kenny's knowledge. but unless he said he saw the picture and still suggest the use of glass - i stand by my statement that I would not add more glass/epoxy

I'm in the middle of a bottom job right now. The glass repair went great and its smooth as can be. Now the gel coat I'm struggling with, as the fiberglass repair is basically flat. Unsure if I should sand the fresh fiberglass down to create a depression or spray the gelcoat to try and form a bigger flat layer of gel coat then i could more easily blend that in. Right now I'm brushing it on. Its also very opaque, so any thin layers the dark fiberglass shows through.

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Nacra 6.0 NA
Ogden Dunes, IN
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After the fiberglass is applied it needs to be faired. During the reapair prep, I removed most of the gelcoat (the hulls will not be any heavier after the repair). You must decide if you are fairing/sanding the fiberglass down to match the surrounding surface, or if you are bringing up the surrounding surface up to match the fiberglass? You
also need to fill the weave or chop pattern in the glass so it doesn't texture through to the gelcoat finish. I fair with West 410 fairing compound and epoxy. Then you are ready for gelcoat. If you skip fairing, you cannot hide/blend the repair. Fairing sanding looks best when a longboard sander is used. After spraying gelcoat (rolling can also be done, but is more work) I sand it and polish to remove the texture. Included are photos (pardon the order, the album got shuffled).

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David
Inter 20
Southern Maine
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Kevin219

I'm in the middle of a bottom job right now. The glass repair went great and its smooth as can be. Now the gel coat I'm struggling with, as the fiberglass repair is basically flat. Unsure if I should sand the fresh fiberglass down to create a depression or spray the gelcoat to try and form a bigger flat layer of gel coat then i could more easily blend that in. Right now I'm brushing it on. Its also very opaque, so any thin layers the dark fiberglass shows through.

Spraying will give you the best results. Buy a cheap $15 CENTRAL PNEUMATIC 20 Oz. HVLP Gravity Feed Air Spray Gun from Harbor Freight. Thoroughly sand the area to be repaired with 220 grit sandpaper (no gloss showing. Blend and mix completely equal parts of Duratec Polyester Clear Hi-Gloss Additive and the gel coat required for the repair. Only catalyze the amount of gelcoat with 2% with MEKP catalyst. Spray pressures should be 35 to 50 psi. Wipe down the area with acetone. Spray the entire surface to be repaired with a fine mist coat and wait 2 minutes for the solvents to flash off. Follow with light wet coats, overlapping the surrounding area to ensure complete coverage. Lightly sand the repair area with 320 to 800 grit sandpaper, either wet or dry, then use Polishing Compound and buff to the desired finish ensuring that the newly gel-coated area is blended with the surrounding gel coat surface. Wax repair area with wax of your choice.

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Kenny Boudreaux
2010 C2 F18 USA 323
Goodall Design "Southern Area Rep"
Owner of Sailboxes.com
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MN3

Kenny i certainly defer to your experience but may i ask why use glass?

if he has no damage and is worn down to the glass but not any further, is more or new glass needed?
Did you see the damage?
it looks very minimal

Edited by MN3 on Apr 20, 2020 - 01:56 PM.

Just now seeing this. If cosmetic build up is required, you need a filler, then gelcoat. Gelcoat has no significant strength, at least compared to epoxy. I would sand the area and apply an epoxy filler. Allow the epoxy to cure to the point where sanding produces a fine powder. Wash away amine blush with water and an abrasive scotch brite pad. Dry the surface with paper towels, or rinse well and allow it to air dry. Apply gelcoat as needed.

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Kenny Boudreaux
2010 C2 F18 USA 323
Goodall Design "Southern Area Rep"
Owner of Sailboxes.com
--

KennyB

MN3

Kenny i certainly defer to your experience but may i ask why use glass?

if he has no damage and is worn down to the glass but not any further, is more or new glass needed?
Did you see the damage?
it looks very minimal

Edited by MN3 on Apr 20, 2020 - 01:56 PM.

Just now seeing this. If cosmetic build up is required, you need a filler, then gelcoat. Gelcoat has no significant strength, at least compared to epoxy. I would sand the area and apply an epoxy filler. Allow the epoxy to cure to the point where sanding produces a fine powder. Wash away amine blush with water and an abrasive scotch brite pad. Dry the surface with paper towels, or rinse well and allow it to air dry. Apply gelcoat as needed.

Kenny, quick one for you. Assuming you're sanding the laid epoxy first in prep for gel adhesion, why is it critical to wash the amine blush? One would assume you're just sanding off that layer.

Quote

Just now seeing this. If cosmetic build up is required, you need a filler, then gelcoat. Gelcoat has no significant strength, at least compared to epoxy. I would sand the area and apply an epoxy filler

+1

thanks for all your input - it is some of the most complete and simplified (and trusted) versions i have seen



Edited by MN3 on Apr 23, 2020 - 12:38 PM.

Headhunter

why is it critical to wash the amine blush? One would assume you're just sanding off that layer

Jon, wash that blush off!

https://www.youtube.com/watch?v=I3E-ppNtfaU

Amine blush is like an oily surface from the epoxy cure (caused by humidity and atmospheric conditions during cure). You need to clean away the oily surface. Cleaning with water or solvent only may leave some amine blush in the nooks and crannys. Light sanding is the best way to remove all of the amine blush. You are not sanding all of the fiberglass and epoxy away, only slightly sanding into the surface for bond preparation so the next layer will stick. If you gel-coat over amine blush or fiberglass over amine blush you will get delamination down the road. Amine blush can also be prevented by putting peel ply over the fiberglass and epoxy before it cures and removing it after cure. This is what many production shops do, but this costs more in consumables.

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David
Inter 20
Southern Maine
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DEFINITELY wash out and wipe down the amine BEFORE sanding. Had a real bad experience doing it in the reverse and only embedded the amine, causing fish eyes.

You can get a fine polyester scrim-type cloth from Wally World that works pretty darned good for peel ply, BTW. And, cheap.

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Chuck C
NACRA 500 Mk2
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Quote

Had a real bad experience doing it in the reverse and only embedded the amine, causing fish eyes.