In reading many post I have come across the mention of this material often. Best I can figure is that it is added to paint or epoxy. Is this for durability or is it for a slicker surface for easier paddling??. Could someone educate me on this process and its usage. :?:
Graphite Usage
- Thread starter olecajun
- Start date
Different builders apply it differently, but it basically does two things. It hardens the epoxy, and seems to make it slicker too. I mix it at 20% of powdered graphite by volume. Three coats provides a full coverage.
On my boats, where they encountered sharp rocks (broken granite, quarts, gneiss, etc.) scratches that traveled from the graphite surface up onto plain epoxy, became deeper digs in the plain epoxy. And, when paddling through lilly pads, weeds, and such, the boat definitely has less resistance. I have not tested with a fixed load and a spring scale, but have paddled the same boat with and without graphite, and can tell a difference.
On my boats, where they encountered sharp rocks (broken granite, quarts, gneiss, etc.) scratches that traveled from the graphite surface up onto plain epoxy, became deeper digs in the plain epoxy. And, when paddling through lilly pads, weeds, and such, the boat definitely has less resistance. I have not tested with a fixed load and a spring scale, but have paddled the same boat with and without graphite, and can tell a difference.
I mix my first 2 coats at 20% graphite and add silica (silica makes it even harder) to thicken it even more so the graphite does not run down, especially on a boat with a vee. The 3rd coat gets mixed at 40% graphite only. Mix enough silica to make it thicker, but not to much so that it will be hard to roll on.
(Only use a foam roller to apply it) Regular paint roller leave too much lent and you will end up with a really rough finish.
(Only use a foam roller to apply it) Regular paint roller leave too much lent and you will end up with a really rough finish.
I've applied mine with a foam brush - but beware. Not all foam brushes are created equally. The best ones I've found had wooden handles, but - not all foam brushes with wooden handles are as good. I've not had good luck with the ones sold locally (Lansing MI) that have plastic handles.
On each, successive coat, I move the masking tape back about an 1/8" so the edge is staggered and not a sharp angle. )Probably good for another 10-15 mph paddling speed. :wink
On each, successive coat, I move the masking tape back about an 1/8" so the edge is staggered and not a sharp angle. )Probably good for another 10-15 mph paddling speed. :wink
I am not going to get in a conflab on this again, this is my take on it and the other folks and builder and racers in my neck of the woods .
Graphite impregnated in epoxy is a sacrificial coat that is used to protect the bottom of the boat and wear off as it is used ,it can be easily seen where your wear is taking place.It isn't harder but it is slicker, as you wear the epoxy of the top of the graphite particles, they don't dissolve , you leave a film of graphite on the outside of your boat and it works great,if you want it slicker we found that a light sanding with a scotch bright pad opens up more of the pores and works well, a lot of racers do this prier to a race.
Silica alum powder work the same way but they are much harder than the graphite so they wear better.
Ron
Graphite impregnated in epoxy is a sacrificial coat that is used to protect the bottom of the boat and wear off as it is used ,it can be easily seen where your wear is taking place.It isn't harder but it is slicker, as you wear the epoxy of the top of the graphite particles, they don't dissolve , you leave a film of graphite on the outside of your boat and it works great,if you want it slicker we found that a light sanding with a scotch bright pad opens up more of the pores and works well, a lot of racers do this prier to a race.
Silica alum powder work the same way but they are much harder than the graphite so they wear better.
Ron
olecajun said:
OK..I am the cause of it on here. I was reading about it making the bottom of the boat slicker ( Racing Sail Boats ) and figured it would work on a boat I paddle threw the weeds and swamps around here. The weeds wanted to stick to the glass and epoxy as I paddled threw them. So I Tried it on one pirogue.
:shock: It made it act like it had 4 wheel drive when going threw the weeds , they did not stick to the bottom but just slide off. Actually a friend was there and also tried the pirogue threw the weeds he came back all smiles and said I have a 4 wheel drive boat with that mix on the bottom.
So I posted my results and before long others were doing the same. The graphite makes the bottom slicker then just plain epoxy which means you have less damage to the bottom when you hit something. I guess you might say it offers more protection because it lets you slide off of something and the extra coats of epoxy , with it in it , does not hurt anything and does offer more protection.
Sanding it does make it slicker since you are removing that outer skin of epoxy covering it with a little graphite in it and getting down to the real mix of it.
I like to do three light coats of the mix and I use a foam roller to apply it...... There will be some bubbles but they vanish as the mix cures. If you are worried about it then a lite brushing with a dry foam brush breaks them up.
Chuck.
Dang, I don't think I ever received such a well answered question as this one. All the info is well appreciated and a great learning experience. Will probably be asking more about this process in the future once I start building a plank pirogue meant for duck hunting.
The dugout which will be the first build will be a natural finish with varnish and is meant for exhibit now and then pasted to my grandson.
FYI: Temp 78, fishing are biting and all honey do's are done. Time to start chopping on a log.
Thanks again for the info.
The dugout which will be the first build will be a natural finish with varnish and is meant for exhibit now and then pasted to my grandson.
FYI: Temp 78, fishing are biting and all honey do's are done. Time to start chopping on a log.
Thanks again for the info.
I have built a racing boat (Touring pirogue TV 19-32) for the 6th running of the MR340 Missouri river ultra marathon. I want it to be as easy paddling as possible, but....
I just have some reservations about the color black. The boat will still spend most of it's life upside down in the sun because I don't have a place to store it under cover.
I worry about UV damage and the heat the black will generate sitting in the sun. Just don't know if the benefit out weighs the perceived dangers.
I am planning on a gloss white finish on the bottom, wax able and slick as I can get it. Don't know if I like the look of the black bottom for this boat either.
Could probably throw a tarp over it when stored if there is a significant benefit in speed. I guess the other benefit is scratch protection. I have made this boat with 1.4oz glass on the bottom and inside to reduce weight so it is quite vulnerable to bottom damage and the graphite would give me a great weight / protection ratio.
I am in a quandary on the graphite issue.
Tom (training in Missouri)
I just have some reservations about the color black. The boat will still spend most of it's life upside down in the sun because I don't have a place to store it under cover.
I worry about UV damage and the heat the black will generate sitting in the sun. Just don't know if the benefit out weighs the perceived dangers.
I am planning on a gloss white finish on the bottom, wax able and slick as I can get it. Don't know if I like the look of the black bottom for this boat either.
Could probably throw a tarp over it when stored if there is a significant benefit in speed. I guess the other benefit is scratch protection. I have made this boat with 1.4oz glass on the bottom and inside to reduce weight so it is quite vulnerable to bottom damage and the graphite would give me a great weight / protection ratio.
I am in a quandary on the graphite issue.
Tom (training in Missouri)
I'm not sure where you do or could store the boat, but if you could have it in the shade then graphite would provide you some benefits. It will generate some heat upside down in the sun. If you lay a tarp on it, raise the tarp with slats of some kind so it doesn't touch the boat. Air circulation will keep the boat dry, and a tarp may get glued to the boat in high sun?
Mine is and has been stored out in the sun with no damage for the last 3 years. It is upside down on a trailer. Only one coat of 20% graphite/80% epoxy over the glassed bottom. The grain of the plywood is still visible through the finish.
The Brightsides ( Interlux ) epoxy ( Marine Polyurethanes) paint from Chesapeake Light Craft has Teflon in it and offers a slippery mix for the bottom and it comes in all sort of colors , I use the Hatteras White on the bottom of some of my boats. Actually on the 14 x 30.. JEM Watercraft Sasquatch and the Pygmy , Coho , kayak while I used the green on the Uncle Johns Bayou Skiff.
Only reason I have not mentioned it on this thread is that it does cost quite a lot.
The primer ( pre-coat) is $26.25 for a quart and the paint is $35.95 a quart plus postage.
Compared to the graphite on cost per boat....I can do two boats with the Interlux , four or more boats with $7.00 worth of graphite.
When done as the instructions tell you and with three coats it does offer bottom protection and is slippery. I ran over a lot of rocks in the Brazos and all that was on the bottom were some scuff marks. Even got hung up on the rocks a couple of times.
Chuck.
Only reason I have not mentioned it on this thread is that it does cost quite a lot.
The primer ( pre-coat) is $26.25 for a quart and the paint is $35.95 a quart plus postage.
Compared to the graphite on cost per boat....I can do two boats with the Interlux , four or more boats with $7.00 worth of graphite.
When done as the instructions tell you and with three coats it does offer bottom protection and is slippery. I ran over a lot of rocks in the Brazos and all that was on the bottom were some scuff marks. Even got hung up on the rocks a couple of times.
Chuck.
Chuck,
Is that put on with a roller or do you spray it? The paint I mean.
I am really looking for a spray can that will work so I can go back and touch up scratches if I need to. I have found Rustoleum to have an etching primer made for glass and aluminum (on their web site not on a shelf locally) but have not found a top coat I am happy with yet in a spray can. Although I have found some appliance epoxy and another gloss white that has epoxy in its name from Ace hardware these seem to have a good hard durable finish (claims anyway).
I wrote to Krylon interested in their paint for plastics and they do not recommend any of their paints for boats (immersion) I wrote them back and complained about too many lawyers it this country and that the boat was not going to be immersed for more than a couple days at a time. The plastic paint seems to make sense to me.
Tom (training in Missouri)http://www.facebook.com/?ref=home#!...&set=a.1534598649512.67478.1371187600&theater
Is that put on with a roller or do you spray it? The paint I mean.
I am really looking for a spray can that will work so I can go back and touch up scratches if I need to. I have found Rustoleum to have an etching primer made for glass and aluminum (on their web site not on a shelf locally) but have not found a top coat I am happy with yet in a spray can. Although I have found some appliance epoxy and another gloss white that has epoxy in its name from Ace hardware these seem to have a good hard durable finish (claims anyway).
I wrote to Krylon interested in their paint for plastics and they do not recommend any of their paints for boats (immersion) I wrote them back and complained about too many lawyers it this country and that the boat was not going to be immersed for more than a couple days at a time. The plastic paint seems to make sense to me.
Tom (training in Missouri)http://www.facebook.com/?ref=home#!...&set=a.1534598649512.67478.1371187600&theater
There is a white graphite powder listed on one of the suppliers web pages.
Here in Texas the black bottom gets hottttttttttttttttttttttttttttttt , so you need to acount for that
Ron
Here in Texas the black bottom gets hottttttttttttttttttttttttttttttt , so you need to acount for that
Ron
Another high-temperature lubricant, hexagonal boron nitride, has the same molecular structure as graphite. It is sometimes called white graphite, due to its similar properties.
That sounds closer to my needs and wants. I am sure it would be a flat finish though. I am having a hard time getting a glossy Gelcoat like finish out of my mind. But after 200 miles of river I might be wishing I had a magic carpet.
Tom
Tom
mosportsmen said:
The closest thing to that gel-coat finish for a wood boat ( That I have found ) is the Interlux Poly paint. Like I said , it is expensive and to top that off it has one bad aroma when using it , it plain stinks , I make sure there is a lot of ventilation in the shop when working with it.
