Graphite paint questions

See our FAQ and tutorials before posting.
terrulian
* Bateau Builder *
* Bateau Builder *
Posts: 2863
Joined: Sat Dec 07, 2013 11:29 am
Location: Marin County, CA
Contact:

Re: Graphite paint questions

Post by terrulian » Fri Jan 17, 2020 10:08 pm

Yes, green on green but wait until the coats are tacky. Can't you tape off sections if you are worried about runs?
Also, you don't want to leave yourself with too much sanding of the cured epoxy/graphite, as it creates dust that gets everywhere and is a pain.


Tony
Image

fallguy1000
Very Active Poster
Very Active Poster
Posts: 5091
Joined: Tue Jan 12, 2010 12:25 am

Re: Graphite paint questions

Post by fallguy1000 » Fri Jan 17, 2020 10:35 pm

terrulian wrote:
Fri Jan 17, 2020 10:08 pm
Yes, green on green but wait until the coats are tacky. Can't you tape off sections if you are worried about runs?
Also, you don't want to leave yourself with too much sanding of the cured epoxy/graphite, as it creates dust that gets everywhere and is a pain.
Oh, it'll be taped off. Just that CL seemed to say the graphite flows down, so it might flow to the outside is all.
My boat build is here -------->

viewtopic.php?f=12&t=62495

User avatar
BarraMan
* Bateau Builder - Expert *
* Bateau Builder - Expert *
Posts: 1475
Joined: Tue Dec 11, 2012 3:44 pm
Location: Australia

Re: Graphite paint questions

Post by BarraMan » Sat Jan 18, 2020 4:06 am

I put graphite/epoxy on the bottom of my boat following Cracker Larry method. Can’t say I would bother doing it on another boat - don’t think it’s worth the bother.

Aripeka Angler
* Bateau Builder - Expert *
* Bateau Builder - Expert *
Posts: 6314
Joined: Thu Sep 13, 2007 9:13 pm
Location: Dade City, Florida

Re: Graphite paint questions

Post by Aripeka Angler » Sat Jan 18, 2020 6:49 am

BarraMan wrote:
Sat Jan 18, 2020 4:06 am
I put graphite/epoxy on the bottom of my boat following Cracker Larry method. Can’t say I would bother doing it on another boat - don’t think it’s worth the bother.
I 100% agree it’s not worth the effort and I’ve done it on two of three boats.
It’s more of a feel good rather than does much good process.
Richard
Completed boats...XF20 "Red Alert", Aripeka Angler's Strip Canoe, FS18 “Bare Bones”, GF12
Currently building...PY12 Kayak
If there is magic on this planet, it is contained in water. - Loren Eiseley
Bare Bones build thread...
viewtopic.php?f=12&t=62146

fallguy1000
Very Active Poster
Very Active Poster
Posts: 5091
Joined: Tue Jan 12, 2010 12:25 am

Re: Graphite paint questions

Post by fallguy1000 » Sat Jan 18, 2020 6:58 am

Aripeka Angler wrote:
Sat Jan 18, 2020 6:49 am
BarraMan wrote:
Sat Jan 18, 2020 4:06 am
I put graphite/epoxy on the bottom of my boat following Cracker Larry method. Can’t say I would bother doing it on another boat - don’t think it’s worth the bother.
I 100% agree it’s not worth the effort and I’ve done it on two of three boats.
It’s more of a feel good rather than does much good process.
Richard,

Do you see the vee section of hull forward of the beaching keel? I am worried about hitting the beach there and taking off all the ablative. It has epoxy primer there in the pic now.

So, graphite/epoxy not that hard?
My boat build is here -------->

viewtopic.php?f=12&t=62495

Aripeka Angler
* Bateau Builder - Expert *
* Bateau Builder - Expert *
Posts: 6314
Joined: Thu Sep 13, 2007 9:13 pm
Location: Dade City, Florida

Re: Graphite paint questions

Post by Aripeka Angler » Sun Jan 19, 2020 8:50 am

I’ve got no way making any claims about the actual hardness of 3 coats graphite/epoxy vs. 3 coats of post fairing neat epoxy. I’m skeptical though, I doubt there’s really that profound of a difference. Cured epoxy is pretty damn hard in its own right.
UV protection was mentioned, but its not very much. Paint a board with the stuff and throw it out in the summertime sun for awhile.
We flipped the GF12 over on the dock uncovered for a couple of months and the black color almost disappeared. It also began to blister like a bad clear job looks when it’s about to fall off. Builders get away with using the stuff unprotected because it’s mostly facing down.
I’d say based on my experience with the GF12 and the XF20, the main advantage is that minor scratches stay black. If you are going with black bottom paint anyway, I’d do the graphite under the paint for this reason. I’d personally never put the stuff on another one of my boats without painting over it.
You’ll get good protection from sand scratches but bigger strikes on rocks and oysters will blow through the stuff as they do on a boat with gelcoat or paint. A 1/16” thick magic force field it isn’t.
We didn’t use the black stuff on the FS18, instead opting for the before mentioned neat epoxy and paint.
So far, no regrets. And real paint also it looks way better IMHO, especially on a small boat. 8)
Richard
Completed boats...XF20 "Red Alert", Aripeka Angler's Strip Canoe, FS18 “Bare Bones”, GF12
Currently building...PY12 Kayak
If there is magic on this planet, it is contained in water. - Loren Eiseley
Bare Bones build thread...
viewtopic.php?f=12&t=62146

fallguy1000
Very Active Poster
Very Active Poster
Posts: 5091
Joined: Tue Jan 12, 2010 12:25 am

Re: Graphite paint questions

Post by fallguy1000 » Sun Jan 19, 2020 10:19 am

Bottom is vivid white which is the color of egg nog.

I will just epoxy prime it Monday a few coats more up there.

Thanks all.

I gotta call Jeff and cancel the graphite.

You know a paint additive that is mean hard?

Cabosil
Last edited by fallguy1000 on Sun Jan 19, 2020 10:32 am, edited 1 time in total.
My boat build is here -------->

viewtopic.php?f=12&t=62495

terrulian
* Bateau Builder *
* Bateau Builder *
Posts: 2863
Joined: Sat Dec 07, 2013 11:29 am
Location: Marin County, CA
Contact:

Re: Graphite paint questions

Post by terrulian » Sun Jan 19, 2020 10:21 am

AA,
I drag my rowboat often on rocks to get it to the water or out. I agree that it certainly is not like a magic shield but my strong impression is that it is more durable than paint as a top layer. Rocks can cut through paint and S3 primer to glass/fairing relatively easily but not so much with the graphite bottom. I can't speak to the UV issue as I don't store my boat upside down in the sun but mine is still black. It looks like crap compared to paint but most boats that are kept in the water have much worse looking hulls under the waterline anyway, even with anti-fouling, just because of growth, and he says he's keeping the boat in a berth. If I were to have fretted over the looks of my big boat under the waterline, I would have had to have a diver clean it every week.
I wonder if the difference in experience is because your boats are heavier, and so the hull is exposed to more pressure from abrasives than mine?
Tony
Image

Aripeka Angler
* Bateau Builder - Expert *
* Bateau Builder - Expert *
Posts: 6314
Joined: Thu Sep 13, 2007 9:13 pm
Location: Dade City, Florida

Re: Graphite paint questions

Post by Aripeka Angler » Sun Jan 19, 2020 1:20 pm

Tony, I’m sure weight is a factor with abrasion results. Good point.
Here’s an old but good read on the subject.

http://forum.woodenboat.com/showthread. ... -questions

Fallguy- since you are going with a white bottom, did you know there’s a white version of graphite?
Richard
Completed boats...XF20 "Red Alert", Aripeka Angler's Strip Canoe, FS18 “Bare Bones”, GF12
Currently building...PY12 Kayak
If there is magic on this planet, it is contained in water. - Loren Eiseley
Bare Bones build thread...
viewtopic.php?f=12&t=62146

terrulian
* Bateau Builder *
* Bateau Builder *
Posts: 2863
Joined: Sat Dec 07, 2013 11:29 am
Location: Marin County, CA
Contact:

Re: Graphite paint questions

Post by terrulian » Sun Jan 19, 2020 5:33 pm

Thanks, AA.
I checked out the string and apparently Gougeon Brothers agree that it increases "scuff resistance and durability." Not sure what durability refers to. But it seems to me that if there is a question between epoxy/graphite as the final coat and paint as a final coat, it's hard for me to believe the former wouldn't be harder. On the other hand, just neat epoxy is also harder than paint, and thicker. So maybe the graphite does little or nothing, I don't know. I had never heard of using it before I got on this forum, and Cracker was a fan, and since I was an admirer of his, I took the bait. It didn't cost didly and it wasn't that much of a pain. People on the wooden boat forum complain that it's a hassle, but, come on, I built a boat. Hassle? My specialty or as the British say, speciality. You can always just buy a boat. :? :lol:

As for drag through the water, I don't give a groat about that as I'm not participating in the Olympics. 8O

As to Fall Guy's suggestion of Cabosil, then why not just use milled glass fibers? You still have to have a topcoat, and since he's using anti-fouling, which will scratch easily, I see some bottom jobs in his future no matter what he chooses.
Tony
Image

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests