hull bottom protection

Has anyone tried fairing (or even glassing 1st) and painting the bottoms of their fiberglass hulls with awlgrip or similar for added protection from rocks/dings/etc? My NACRA 20 lives at the beach in CT and it's quite rocky. While I don't ever intentionally run it up the beach, it's still getting scratched up from "incidents." I don't ever leave it out of the water except on beach wheels and stern supports.
Yes. It didnt stop scratches and white scratches in gray paint stood out. Save your time, money, and the weight
I wholly agree with MN3.
If it is strength you are worried about, use a better epoxy resin to build your bottoms back up.
Epoxy resin adheres well to polyester resin with proper prep, unless you apply it in the cold, but whatever you use to cover it - gelcoat/paint - will still scratch and show the resin/cloth below.

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Sheet In!
Bob
_/)_____/)_/)____/)____/)_____/)/)__________/)__
Prindle 18-2 #244 "Wakizashi"
Prindle 16 #3690 "Pegasus" Sold (sigh)
AZ Multihull Fleet 42 member
(Way) Past Commodore of Prindle Fleet 14
Arizona, USA
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QuoteMy NACRA 20 lives at the beach in CT and it's quite rocky. While I don't ever intentionally run it up the beach, it's still getting scratched up from "incidents." I don't ever leave it out of the water except on beach wheels and stern supports.

When I bought the G-Cat I'm currently sailing I noticed that the previous owner had done a "Bottom Job" that leaved a lot to be desired. I don't know what kind of cloth and resin was used and it's held up fine, but it was used in great excess and was far from smooth. So, I started sanding and sanding and sanding. It appeared smooth, but after I applied gelcoat, I could see many flaws made visible by the glossiness of the gelcoat. I came to the conclusion that fairing is a real skill, much harder than I thought.

Another point I wanted to make is that you want to keep your hulls off rocky beaches in the first place. I know you're probably saying "duh", but I have the same issues, so I anchor in about 2 feet or less and finish rigging the boat there. If your boat wants to move around too much use a bow and stern anchor to position it how you want it relative to the wind. If you don't want to sail with an anchor, just leave it there with a bleach bottle for a marker. This all depends on how calm it is where you're launching and if there's any kind of shore break what I suggested is moot and you'll have to live with scratches.

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Bill Townsend
G-Cat 5.0
Sarasota
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White Marine Tex works well for a quick fill on scratches and gouges. I have one boat that is heavily invested in Marine Tex and another "pretty" one that the hulls don't touch grass or fine sand. I agree with Shortyfox on anchoring out. When I race at Canyon Lake singlehanded, I use a mushroom anchor and Ultralight line (floats) to anchor the boat out while I move beach wheels around. It's pretty flat there, so if you have waves a more substantial Danforth, CQR, or Mantis anchor would work better.

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Scott

Prindle Fleet 2
TCDYC

Prindle 18-2 Mod "FrankenKitty"
Tornado Classic "Fast Furniture"
Prindle 19 "Mr. Wiggly"
Nacra 5.8 "De ja vu"
Nacra 5.0
Nacra 5.8
Tornadoes (Reg White)
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Quoteust leave it there with a bleach bottle for a marker


I hate this practice. (usually the float is not near the actual anchor)

it creates underwater hazards for people and boats. nothing like a punctured foot or boat to start out a fun weekend on the water
3M tape works well on our cat. It's expensive but easier than epoxy work.

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John

Nacra 5.0
CT
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it is not that hard to keep a small container of gelcoat and a small bottle of catalyst and do spot repairs.
Topcat sells "keel shoes" for their boats. My understanding is that it is a strip of rubberized plastic but I could be wrong. I don't have them on my boat. https://youtu.be/GRGrl9ycXVc
danielt1263Topcat sells "keel shoes" for their boats. My understanding is that it is a strip of rubberized plastic but I could be wrong. I don't have them on my boat. https://youtu.be/GRGrl9ycXVc

Nice! those look like they are the right solution if you like hobie beaching your brand new boat! :)

It is a lot of extra work to keep your boat 100% off the ground/sand and almost impossible for solo sailors.

At our beach several long time cat sailors have put alum stips into the keels on their hulls - works to a degree but like everything has trade offs (holes in your hulls = new leak spots, a lot of work to embed and fair into the hull, limited use before maintenence gelcoat is needed (depending on how often you fly up a beach), etc)

in the long run the metal was removed in favor of saving a few pounds per hull as those same sailors were also racers



Edited by MN3 on Aug 13, 2023 - 12:19 PM.
I've been very happy with taping off an area, similar to the above video, sanding the gel coat down a tad (not as much as the dude in the video), wipe with acetone and paint on a mix of West system slow set epoxy with graphite mixed in pretty thick. Way tougher than polyester gel coat and real easy to touch up. Two years in and I've jut noticed a very small area near one stern that's starting to wear through. I'll do a winter maintenance, flip the hulls, sand and re-coat all in a Saturday morning. Well, taking it apart will take WAY longer.

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Chuck C
NACRA 500 Mk2
Hobie 21se (sold)
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I purchase High-Strength Vinyl Ester Resin from Fiber Glast and plan on buy 10 yards of 4" wide Kevlar Tape to add some material to my buddies Hobie 18 hulls.....many years of beach rash,we all seem this before....my fiberglass buddy wants me to spread heavy visqueen on a table top, pour a resin mix down , lay a 5' piece of 6" wide fabric tape in that resin, squeeze to the resin, pour more resin on top of this tape, squeeze this top resin throughout the fabric tape and roll this mess on a piece of PVC pipe and now unroll this mess to a hulls.....squeeze again and a repeat with two more 5' pieces to finish one hull......with three people working together , this sound fairly simply.....what am I missing? We plan on leaving this bottum job without painting..... icon_smile .....any advice here.....

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Bill 404 21SE
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I refinished the skeg hulls on my Nacra 5.7 with Kevlar, but found I needed to finish with fiberglass and thickened microfiber to be able to properly fair it. Kevlar gets incredibly fuzzy when sanded and is a good subsurface structure to withstand impacts, but it sucks to finish. Paint it. Epoxy has poor UV resistance.

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Tom
NACRA 5.7 (1984 Sail 181)
Pennsylvania
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When repairing my rudders and centerboards, I use Solarez Extreme. It is a gel that goes on easily and can be hardened in the sun in 5 minutes. You can expose it for a minute and get it hard enough to shape with a razor blade, then expose it fully and sand it to final shape. You can gelcote over it if you like. It will be stronger than your original material. Watch the video to see how to use mylar to shape the repair.
https://solarez.com/vinyl…ter-solarez-extreme.html
On your hulls, to fix punctures, use the Solarez that is in the blue tube, as it will not melt the foam under the fiberglas.
https://solarez.com/epoxy-ding-repair.html
I have been using these products for a long time now, and once had a guy on the beach pay me twice the cost of a new tube for a half full remnant.
You can permanently make a strong repair on the beach, working in the shade and then exposing it to the sun to harden. Amazing stuff.
This is not a paid advert.

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Sheet In!
Bob
_/)_____/)_/)____/)____/)_____/)/)__________/)__
Prindle 18-2 #244 "Wakizashi"
Prindle 16 #3690 "Pegasus" Sold (sigh)
AZ Multihull Fleet 42 member
(Way) Past Commodore of Prindle Fleet 14
Arizona, USA
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