Graphite paint questions

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joe2700
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Re: Graphite paint questions

Post by joe2700 »

I've also never been sold on the graphite bottom. To my mind if you are going to add the weight of more epoxy to the hull then you might as well use it it to add another layer of glass, or even kevlar if you really plan to drag it over rocks. Seems like that would add more protection than neat epoxy with a bit of graphite. Also, neat epoxy over fairing compound undoes a lot of the nice fairing unless you do a bunch of sanding after applying, neat epoxy never goes on that smooth. All that said the graphite bottom is popular on the forum and I haven't tried it myself, so I normally keep my mouth shut about it. :D

I also think there's just regional differences. Almost all boats where I am use bottom paint, whether they are in the salt water all season or trailer launched into it. If you wear through the bottom paint you need to repaint anyway to prevent growth, so the graphite doesn't seem very useful. There's not nearly as much focus on shallow water performance so I imagine we are fishing places you hit the bottom a lot less, or it's sand when you do. I've never in my life seen a boat with a polling platform other that on this forum.

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Re: Graphite paint questions

Post by Capt UB »

joe2700 wrote: Mon Jan 20, 2020 2:00 am I've also never been sold on the graphite bottom. To my mind if you are going to add the weight of more epoxy to the hull then you might as well use it it to add another layer of glass, or even kevlar if you really plan to drag it over rocks. Seems like that would add more protection than neat epoxy with a bit of graphite. Also, neat epoxy over fairing compound undoes a lot of the nice fairing unless you do a bunch of sanding after applying, neat epoxy never goes on that smooth. All that said the graphite bottom is popular on the forum and I haven't tried it myself, so I normally keep my mouth shut about it. :D

I also think there's just regional differences. Almost all boats where I am use bottom paint, whether they are in the salt water all season or trailer launched into it. If you wear through the bottom paint you need to repaint anyway to prevent growth, so the graphite doesn't seem very useful. There's not nearly as much focus on shallow water performance so I imagine we are fishing places you hit the bottom a lot less, or it's sand when you do. I've never in my life seen a boat with a polling platform other that on this forum.

Joe I agree with you on covering the softer fairing bottom with graphite and epoxy, I did not fair the bottom of SandPiper other than filling with a neat coat of epoxy. I did do 3 layers of graphite/epoxy (it was not a little graphite) on the bottom, using it as fairing mix! After a week, I did sand carefully the bottom with wet/dry sanding block (wet). I only trailer her, so no bottom paint, the graphite is so smooth it's hard to hold on to the bottom!! I'm glad I used it, hit a few bad things.

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Jaysen
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Re: Graphite paint questions

Post by Jaysen »

Things graphite didn't stop (v12 sailing/rowing)
* One oyster very hard oyster shell that I got hung up going "full speed"
* Dropping the 150lb hull with 100lbs of gear right on the keel onto concrete from about 2 feet.
* Smashing into an oyster covered piling
The above all made it through as least one layer glass too...

What it has survived
* dragging up concrete ramps.
* several miles of dragging through mud, oysters, sand, gravel to get into marsh pools at low
* beaching on stand/shell at speed
* dragging through breaches/yard (sand) to launch
* dragging on asphalt because someone's trailer idea sucked.

I think the graphite is about abrasion more than impact. Tony is much nicer to his boat than I am so he is likely seeing better results than those of us that just smash into shit because it's in the way. And at a certain speed "rubbing" becomes impact. How i do that in a v12 is entirely explained with the phrase "dumb ass".

But that's just my opinion
My already completed 'Lil Bit'. A Martens Goosen V12 set up to sail me to the fishing holes.
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terrulian
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Re: Graphite paint questions

Post by terrulian »

I also have the bronze strip protecting the skeg, which is also first covered with two layers of glass. Without the bronze, I'd have gone through to bare wood by now.
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VT_Jeff
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Re: Graphite paint questions

Post by VT_Jeff »

terrulian wrote: Fri Jan 17, 2020 8:16 pm
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Tony, do you have a photo of the front of that bottom? I'm debating if I should graphite the waterline, which would leave part of the bottom white near the bow, or just go an inch or so up the side all the way around. Interested in what yours looks like, looks amazing btw, nice work!
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terrulian
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Re: Graphite paint questions

Post by terrulian »

A little hard to see since the hull is dark blue. The black epoxy coat goes about an inch or so above the chine, since I figured that the boat is sometime going to touch at the skeg and the edge of the bottom.
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Here's an earlier one with primer only.
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VT_Jeff
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Re: Graphite paint questions

Post by VT_Jeff »

terrulian wrote: Thu Feb 13, 2020 6:44 pm A little hard to see since the hull is dark blue. The black epoxy coat goes about an inch or so above the chine, since I figured that the boat is sometime going to touch at the skeg and the edge of the bottom.
Appreciate it. I think I'm leaning towards waterline but I change my mind every 5 minutes. I like the idea of the visible part of the bottom being white(or whatever I eventually paint the hull), but also think the "Rand" effect that you have is cool. Decisions decisions decisions!
There are only two seasons in Vermont: boating season, and boat-building season.

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BrianC
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Re: Graphite paint questions

Post by BrianC »

When putting on a graphite+epoxy coating, do you remove the tape and retape after each coat or just put down all three before removing the tape?

Sorry to add to an old thread but my question seems to fit here.
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terrulian
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Re: Graphite paint questions

Post by terrulian »

I put three coats of graphite/epoxy over System Three primer without removing the tape; then after it had completely cured, say 2 days, I re-taped to expose the topsides and cover the graphite, to apply the topcoat. The epoxy/graphite mix is thick enough that it would show if you just roughed it out, taped it up, and applied the topsides paint down to the tape. You'd see the roughness of the graphite beneath the paint.
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