Solo expedition build

[stripperguy]

Alan,
I like those trapezoidal section gunnels for their water shedding ability. Water, and lots of it, can get trapped inside the hull by the gunnels. If you think you'll be carrying a lot, you'll appreciate a profile that lets the trapped water flow out, instead of onto your arms and into your armpits!!
But, those rounded and oval sections are much easier on the eyes...and provide more grip when handling the boat.

Now, how about that CF, do you plan to wrap around the entire gunnel section and onto the hull? Or will you only CF wrap the gunnel section itself?
Overlapping to the hull will improve the strength, but you may not need that extra strength. Sticking to the gunnel only could make for a very clean line...maybe you'll trim any excess CF from the gunnel while still semi cured.

 

[wgiles]

From an engineering perspective, the deep slot in the gunwale that fits over the strips is a stress riser and could cause the gunwale to split. If you plan to cover the entire shape with carbon fiber, particularly if you wrap the fiber into the slot, and fill the gap between the gunwale and body with resin, this may not matter. If everything is bonded to everything else, it will act as one solid shape. I have not yet built a canoe, but find these discussions fascinating and very informative. Thanks.

 

[Jim Dodd]

I'm betting by now you've made the choice on your gunnel profile, but I'm wondering how you will fasten thwarts ?
Also a consideration, is my legs always rub against the gunnels while paddling, might not want too sharp of a edge.

Lastly the gunnels riding on a roof rack, might be a consideration as far as wear. An unpadded truck rack can be hard on them.

Great Stuff Alan !

You might want to test that canoe on Lizard Creek, West of Ft Dodge ! I'd be glad to guide !

Jim

 

[Alan Gage]

Alan,

Now, how about that CF, do you plan to wrap around the entire gunnel section and onto the hull? Or will you only CF wrap the gunnel section itself?
Overlapping to the hull will improve the strength, but you may not need that extra strength. Sticking to the gunnel only could make for a very clean line...maybe you'll trim any excess CF from the gunnel while still semi cured.

Trimming it while green is a thought that hadn't occurred to me, good idea. I've got 4" tape so depending on the profile I choose it doesn't leave much to overlap the hull. My thought was to try and keep the edge of the tape in line with the gunwale/hull seam on the outside and leave all the overlap on the inside, where it would be less visible. My kevlar tape, if I decide to use it, is only 3" wide to ensure it remains buried by carbon and fiberglass.

From an engineering perspective, the deep slot in the gunwale that fits over the strips is a stress riser and could cause the gunwale to split. If you plan to cover the entire shape with carbon fiber, particularly if you wrap the fiber into the slot, and fill the gap between the gunwale and body with resin, this may not matter. If everything is bonded to everything else, it will act as one solid shape.

I've been wondering about that too. The gunwale will be attached with thickened epoxy and then completely wrapped in carbon and fiberglass, so I'm hoping that will sufficiently bond everything together so that thin bit doesn't matter. On the final gunwale I don't think the kerf will be quite as deep, I worry a little about breaking it during install as I force it to the shape of the hull.

I hadn't thought of putting cloth into the kerf, not a bad idea. It would have to be a separate piece of piece of cloth since if the cloth used to wrap the gunwales was pinched in that kerf I'm afraid I'd never get the wrinkles out.

I'm betting by now you've made the choice on your gunnel profile, but I'm wondering how you will fasten thwarts ?
Also a consideration, is my legs always rub against the gunnels while paddling, might not want too sharp of a edge.

Lastly the gunnels riding on a roof rack, might be a consideration as far as wear. An unpadded truck rack can be hard on them.

Good thought. My Bell aluminum gunnels are hard on the knees for that reason. I keep meaning to add a little foam padding but never do. I always have some foam between my gunwales and rack when car topping but I think the outer layer of fiberglass would prove pretty tough.

Thwarts will be composite as well and joined to the gunwales with more carbon/fiberglass.

And no, I have not come to a decision on the gunwale profile yet. I've got another day or so to ponder it before I do the actual cutting.

Alan

 

[Alan Gage]

You might want to test that canoe on Lizard Creek, West of Ft Dodge ! I'd be glad to guide !

Jim

Looks like a nice spot, I might take you up on that.

Alan

 

[wysedav]

One other thing to be concerned with is the gap from gunwale to deck. I think you're going to have a structurally stiff gunwale and deck with a springy section in between. The gunwale is going to transfer the load s to the springy section and you might have problems. Might want to reconsider and run them into the deck.

 

[Alan Gage]

One other thing to be concerned with is the gap from gunwale to deck. I think you're going to have a structurally stiff gunwale and deck with a springy section in between. The gunwale is going to transfer the load s to the springy section and you might have problems. Might want to reconsider and run them into the deck.

I figured that the gunwale would die into the deck, so they'll be butted together. Are you thinking that butt joint might cause a problem? I wouldn't think that section of the the hull would see a lot of stress and that having them butted together with carbon would be plenty strong. But I don't think with an engineer's mind either.

Alan

 

[wysedav]

No I think you'll be ok. I was worried you were stopping before the deck. Just make sure the joint is strong enough to transfer any gunwale loads to the deck. If your doing a simple butt joint I'd add some fiberglass.

 

[wysedav]

Ohh carbon works too.

 

[Alan Gage]

Lots and lots and lots of sanding to go from this:


20150311_002 by Alan Gage, on Flickr

To this:


20150320_001 by Alan Gage, on Flickr

From this:


20150311_003 by Alan Gage, on Flickr

To this:


20150320_002 by Alan Gage, on Flickr

From this:


20150309_004 by Alan Gage, on Flickr

To this:


20150320_003 by Alan Gage, on Flickr

I think I'm going to go back to squeegeeing my fill coats. I get in too big of a hurry to get it filled so I roll them on thick to get a better build. That results in a less than perfect finish that just gets worse with every coat and lots of sanding to flatten it all back out in the end. I'll still apply the fill coats with either roller or brush but I'll use the squeegee to help spread it around and remove any excess.

I should have put peel ply on the edges of those S-glass layers that top everything else. That stuff sands a lot harder than regular e-glass and tapering that edge is where the vast majority of my time was spent.

Only sanding left to do on the outside is the knuckle once I flip it upright again and that should go pretty quick. I'll probably give the whole exterior one more skim coat of epoxy to cover the glass that was cut into when tapering the edges.

Scarf gunwales and more sanding tomorrow.

Alan

 

[Canotrouge]

Wow you must love sending.... Good for you it looks great!!

 

[memaquay]

Looks really nice! Will you be varnishing the hull as well? Does the pigment provide any enhanced UV protection?

 

[Alan Gage]

Wow you must love sanding.... Good for you it looks great!!

You know, now that I have my new Mirka sander and a big supply of sandpaper with multiple pads I almost do enjoy it. I certainly don't dread it like I used to.

Will you be varnishing the hull as well? Does the pigment provide any enhanced UV protection?

Good questions and I don't know the answer to either of them! I've always heard that tinted epoxy will provide some UV protection but not a lot. How much truth to that there is I don't know since it's just what I've read on internet forums.

I'm reluctant to varnish because I kind of like the color as-is and I know the varnish will add a brownish tint. Water based spar varnish would be clear but probably less UV protection as a result. What I'm really leaning towards is giving it a coat or two of paint that match the pigmented resin. That would give ecxellent UV protection and while it will certainly scratch and chip they'll be nearly invisible since the hull underneath is the same color.

But what to paint with? Spray on a fancy water based two part paint from system 3? Brush on a fancy oil based paint like Interlux? A less fancy oil base like Sikkens Cetol? Or just go to the hardware store and get some oil based enamel?

Right now I'm inclined to go the hardware store enamel route knowing no matter what I put on it's going to get beat up pretty bad.

Alan

 

[Mihun09]

Get one of those epoxy concrete floor paints tinted to match your pigment on the boat so scratches really don't show at all and the epoxy would be a harder finish to take the punishment the Bloodvein will provide.

 

[Alan Gage]

Thanks for the concrete floor epoxy idea. Looked locally and all I could find was a Rustoleum product called "Epoxyshield." It's single part, water based, and described as a "self priming acrylic paint". Doesn't sound too epoxyish to me, think I'll keep looking.

Spent more time walking than working on the boat today. A little chillier but still nice with sun and very little wind. Found a nice protected hillside on the prairie and took a 1/2 hour nap in the sun, very pleasant. But I did get the knuckle sanded, ripped and scarfed the gunwales, and started playing around with some carbon tonight. I've got a 1/4" foam deck and foam thwart in the vacuum bag. Anxious to see how they turned out in the morning. That carbon sleeving is some pretty neat stuff, too bad it's so expensive.


20150321_001 by Alan Gage, on Flickr

Alan

 

[Holmes375]

Lookin' good, Alan. That vacuum bag process is very interesting.

 

[Mihun09]

I honestly don't know how they can have a water based epoxy, doesn't quite go together in my mind. Anyway, HD has it, tint-able to whatever you wish I have been told in the past. A tad pricey for the 2 part system, the single part epoxy is less money.

- Available in pre-mixed and custom colours.

http://www.homedepot.ca/product/behr...er-grey/939032

http://www.homedepot.ca/product/1-pa...ay-379l/938962

Canadian pricing so much less in the USA I would surmise.

 

[memaquay]

I just use an oil based marine paint. Good luck finding any of that now, as the VOC nazis are trying to get rid of all oil based paints and varnishes.

 

[Jim Dodd]

Vacuum bagging ! I've pondered this for many years ! Saves big time, on resin, but the money put into bagging supplies, more than makes up for it.
The weight savings is the real issue !

What did you use for a vacuum pump ?

I've heard of guys using old refrigerator compressors.

Lovin it !

Jim

 

[stripperguy]

Alan,
Do you have a Keystone distributor near you? They provide aftermarket LKQ autobody paints and body work supplies.
A base coat/clear coat sounds like it could work for you, or maybe just the clear coat.
Actually, any autobody supply could provide you with a low cost (relatively) solution.

My daughter and SIL moved into their new home yesterday, taking with them all of SIL's vacuum bagging supplies...I guess I have to commit and get my own stuff now.
Where did you get your peel ply and bagging supplies?