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  #1  
Old 09-29-2007, 09:07 PM
canoe42 canoe42 is offline
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Major overhaul of fiberglass canoe

Looking for advice on repairing a fiberglass canoe. This is not a simple repair but a major overhaul.

A neighbor gave me an old 15' fiberglass canoe made by Moise Cadorette Inc. of St. Jean Des Piles, Canada. The gelcoat is cracked all over. The cracks are deep enough to catch the blade on my jacknife but the gelcoat is not loose. I can not pry pieces off with my jacknife. The canoe handles well. It tracks straight as there are 3 keels, one in the center and one on either side. It is a great solo canoe as it is only 15 feet long and 36" wide.

If I can sand down the old gelcoat enough to make a new coat of either spray-on or brush-on gelcoat adhere and fill in the cracks, finish smooth and maybe paint, I'm up for it. If I need to completely remove all the old gelcoat and start over, I''ll most likely use it as is.

Thanks for your help,

Tom
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  #2  
Old 09-29-2007, 09:20 PM
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the1much the1much is offline
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all you gotta do is fill in all those cracks,sand them out before applying your filler, then sand it till all "shiny" is gone and re- gel-coat. the new gel-coat will come out with "orange peeling" if you want a smooth glass like finish start finish sanding then wet sanding, but if you can live with how it is now, then i would skip the final sanding.
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  #3  
Old 09-30-2007, 07:55 AM
canoe42 canoe42 is offline
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Thanks for the advice. It sounds like refinishing the cracked gelcoat will not be as difficult as I thought. I am a little unclear about what you said though.

Sounds like I need to sand down the cracks in the existing gelcoat (the cracks have a raised edge) to the level of the rest of the gelcoat, apply "filler" (gelcoat? or fiberglass?) sand smooth, apply more gelcoat and sand to as smooth as I want.

Can I get a decent finish if I paint on the gelcoat or do I have to spray it on? Have a painting compressor but would need to get a sprayer. Painting it on would be easier because I wouldn't have to worry about paint dust covering everything in my garage.

Thanks,

Tom
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  #4  
Old 09-30-2007, 09:21 AM
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the1much the1much is offline
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where to in maine are ya? im from maine, i came down to texas 5 years ago, but if your near a boat yard i probably worked for them, boat yards hired me to do their "hard stuff". ,,what ya need to do is sand the cracks first, so the filler will stick in them,small cracks(3 hairs deep) dont worry about the filler should stay, but deeper then 3 hairs and you need to make the crack a V shape. the filler should be a light weight filler. they make so many different kinds, go to the local boat yard and ask them for a small cup full, im pretty sure almost all boat yards in maine will sell ya a small cup so you wont have to buy the whole can. after filler, you need to sand the whole boat with 320 grit till everything is smooth. the painting on of gel coat i've never tried, im slow so painting on a paint that "kicks off" in 5 mins sounds like too much running, and not enough time to do it right, and will cause WAY more sanding after.ive painted on small unseen areas before, but thats it. for headache reasons i would spray it on even though it does put overspray out there. but if ya put your air pressure down it should'nt get to bad. that and go to salvation army and get a bunch of sheets to put over everything in the garage. and for a gun ya need a cup gun , because of the gel kicking off you throw the cup away, fill another and keep going. with your canoe you might go through 3 cups. if your close enough to one of my friends they might have a gun you can use.
the biggest thing to remember is the final paint job just shows your prep work. so prep is most important if you want a good finish
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  #5  
Old 10-02-2007, 01:45 AM
ondarvr ondarvr is offline
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Re-gel coating is probably more work than you want to do, so might want to use paint, it will cost less, look better, and be much faster. Use a filler that is designed to at least be used around water, then use either a 1 part, or 2 part marine paint. 1 part paints are easier to use and cost less, but are not as durable as 2 part types.

You can use a roller and brush with the paints and get a very good surface, smooth and glossy, just follow the directions.

You don't actually need to use a marine paint though, canoe's don't normally spend enough time in the water to do any damage to most good exterior grade high gloss brands you may find at a hardware store. You just won't get all of the online instruction and help you will get with a name brand marine product.
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  #6  
Old 10-02-2007, 05:13 AM
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rwatson rwatson is offline
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My observation is that the cracks in old canoes are usually caused by compression from impact and hard use, and gelcoat is a bit more brittle than the underlying composite. Even so, some of the cracks may extend into the glass itself.
I would conside doing all the preparation as has been described before, but brushing in epoxy resin to the cracks, then sanding back and painting.
The epoxy may bind the gelcoat together a bit better than fillers, and is certainly as waterprooff as you could want.
I would be inclined to brush the level decks first, then after that is cured, roll it over and do the bottom,, epoxy that, then lay it on its side etc. This is because you would want to use a very 'runny' epoxy to completely fill the cracks, and it would run out on vertical surfaces. You can always do extra coats if required.
The advice about 2 part paints is good - usually it goes on really well, dries before too much dust and insects get involved, and takes a lot of wear.
Certainly beats building the craft from scratch, good luck.
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  #7  
Old 10-02-2007, 07:58 AM
canoe42 canoe42 is offline
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Thanks for all the good replys. Although it will be alot of sanding, it sounds like I can do this.

I gather the best thing to do is sand out the cracks as much as possible, fill with filler or epoxy and sand and paint with 2 part marine paint. Re-coating with gelcoat might proove to be too difficult and add more weight than paint. The intended use for this canoe is for solo morning and evening fishing on a flat river we live on, no white water or camping trips.

The canoe does not look like it has seen hard use. No signs of cracks in the fiberglass from the inside of the canoe, although there might be cracks where I can't see them. The neighbor who gave me the canoe got rid of it because it is too tippy to take her kids out in it. The canoe looks like it was left in the water summer after summer. Lots of staining from marine growth from the waterline down.

I gather I can do this outside as someone mentioned the 2 part paint drys fast enough so dust and bugs will not be a problem. Am not going to to this project until next summer. A little cold in Maine right now and my garage is unheated. I also need to replace the thwarts and wood seats. One seat is gone and the other is not far behind it. Will post some pictures when I get a chance.

Thanks for all the help,

Tom
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  #8  
Old 10-02-2007, 08:09 AM
canoe42 canoe42 is offline
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the1much - We live in Litchfield, a little south of Augusta. There is a boat yard in Manchester called Clark's. Have never been there but my neighbor trades there. They sound like they are a full service boat yard and may be able to give me some advice on repairing fiberglass.

Thanks for the loan of a paint gun. I think I will buy one anyway as I plan to do some body work on my car. I also have a 16' Jonboat I plan to convert to a Bassboat some time, but that's another project.

Thanks,

Tom
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  #9  
Old 12-30-2009, 12:56 PM
canoeaholic canoeaholic is offline
 
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Fiberglass Canoe Restoration

I have a similar restoration project.


I have a 14' fiberglass canoe. It is just the hull and mahogany gunwales. It has no thwarts, yokes or ribs. The previous owner was in the process of restoring it when he sold it. It has no leaks.

I am thinking about putting Kevlar in the bottom and up the sides about 3" to 4" inches. Then install 5 wooden ribs with fiberglass cloth and resin over them. I am looking to give the canoe strength and a more ridge shape. Will the ribs be enough and give me what I am looking for? Or is the Kevlar needed? I will be installing Kevlar skids.

I am concerned because I have read that fiberglass is one of the weaker materials that canoes are made of. I don't plan on white water canoeing, just lakes, rivers and camping trips.

Any advice that you can give is appreciated. Thank you.
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  #10  
Old 12-30-2009, 02:08 PM
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Fanie Fanie is offline
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Canoea,

Fiberglass is stronger than you think. I had a 4m200 canoe once, it was 1m wide and very nice to fish from in small dams. Had a trolling motor fitted to it too which worked quite well.

I would make some L brackets and rivit them to the side of the canoe. The seats gets screwed on top of them and will add some structure.

What will also work well is to buy a length of PVC pipe, split it down the middle and fit it over the canoe sides. Four layers of 450g woven overlapping the PVC on the canoe sides about 50mm would stiffen it up enough. A 38mm OD PVC pipe should be ok. It would also make a nice rounding to hold on to. Put peel ply over the last layup, you tear it off after the glass cured. It leaves a surface that is easier to finish off (instant sandpaper).

I would also suggest you put rivits through the length of the new layup where it overlaps the old. Alu rivits works very easy, you support them on the inside with an anvil of sorts and tap them on the outside. It looks like a flat button inside and outside. The idea is to prevent delamination.

If you box the ends it also makes a big difference to stiffen the canoe. I had holes in mine and all the loose stuff goes in there.

With the seats fitted, the gunnel strengthened and the ends boxed I'm sure it should be ok.

Sand down and lastly paint. Choose a light colour or the sun will bake you like an egg on it.

Lastly, could I suggest you get some closed cell PE foam sheeting of about 30kg/sq m, 10 to 15mm thick and glue this to the inside. It will make the interior soft to the touch, non skid, add floatation. Always a nice thing if your boat is unsinkable, so you may really consider it.

Do post some pics, will you ?

Sorry, afterthought - keep the seats down low, it will improve your center of gravity and make for a safer canoe !
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  #11  
Old 12-30-2009, 10:34 PM
SamSam SamSam is offline
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Well, canoeaholic, my advice is don't get carried away. The original poster had a canoe with 3 keels and the gelcoat cracked all over. Nobody in their right mind designs a canoe with 3 keels. Gelcoat cracked all over is an indication of crappiness. The canoe was a POS to begin with, that's why someone gave the thing to him. What he wanted to do was way more work and expense than the thing warranted.

Here's the rest of that story....
Looking for advice on decent spray gun

Post some pictures. You already have gunnels so you won't need the pvc pipe and 1800 grm woven.

A 14' canoe is hardly big enough to be weak. Why do you think it needs to be strengthened? What brand is it? Do you know what it looked like before? Did it have ribs to begin with? If you start glassing stuff in, you might add a lot of unneeded weight.

You can clamp a few temporary thwarts to the gunnels and take it out to see if it needs reinforcement and where you might want to locate the seat, odds are at 14' it's a solo canoe. Looking at other canoes might give you some ideas.
http://www.wenonah.com/products/temp...f782c4587e7933

.
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  #12  
Old 12-31-2009, 12:18 PM
canoeaholic canoeaholic is offline
 
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Photos of my canoe

In the photos, you will see the cracks in the gelcoat. There are a good number of them. Is it like painting a house? Scrap off the flaking paint, sand and then paint over it.
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Major overhaul of fiberglass canoe-hull-cracks.jpg  Major overhaul of fiberglass canoe-keel-crack.jpg  Major overhaul of fiberglass canoe-canoe.jpg  

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  #13  
Old 12-31-2009, 02:23 PM
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Fanie Fanie is offline
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Picture one shows paint peeling, that doesn't look like gell coat to me.

Picture 2 shows damage to the keel, and more like it has been broken, probably by standing in it with a rock under it. You will have to fix this. This keel is part of the backbone of the canoe.
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  #14  
Old 12-31-2009, 06:41 PM
SamSam SamSam is offline
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Well, it's a homemade canoe of some sort, so it might be gelcoat but it looks more like paint. I wouldn't get too involved with it other than to make it good enough. It's got a nice slim shape to it with tumblehome to make it easier to paddle, but pretty crude looking construction.

Do you think the bottom is too flimsy, is that why you want to strengthen it?

Grind the cracks and breaks a little and patch with glass, epoxy is best. Sand the outside, cutting into the glass as little as possible and then paint with a roller and tip with a brush. I just today saw at Home Depot 1 part Rustoleum Bottom Paint for boats, black or blue, for $11 a quart. When I made canoes, I always used latex porch and floor enamel on the inside, all kinds of colors were available, it was cheap and easy and weighed a lot less than gelcoat. If it was mine I think I'd put a kayak type seat in it, where your legs are stretched out and there is a backrest or seat back, and then use a kayak double paddle. Or you can put a regular canoe seat in it like how fanie suggested, with angles and rivets, or you can just kneel in it with your butt resting against a thwart, like an Indian.
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  #15  
Old 01-09-2010, 10:24 AM
canoeaholic canoeaholic is offline
 
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The guy I got the canoe from was in the process of restoring it. I don't know if originally had ribs or if he was going to put ribs in it. I have not yet put the canoe in the water. The canoe has a crease in the bottom and I will need to put a rib in that area to re-enforce it. So thought I would place evenly spaced ribs the length of the canoe. My father-in-law suggested wood ribs, 1/4" thick. I have been emailing a guy the does restoration for a living and he suggested one layer of carbon fiber then fiberglass over that. I am leaning towards the carbon fiber idea more because the profile will be smaller. I am thinking of placing about 3 to 5 of these ribs.

The canoe is actually 15' 6" I will be installing two seats.

For the outside coating, I would like not use paint. I would something that would be thicker. Did that Home Depot Rustoleum Bottom Paint give a thick coat? Or is it more like paint? I am looking for something that will leave a smooth glossy surface.


Thank you for your help.
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