Help - Search - Members - Calendar
Full Version: WOT: Dad's kevlar canoe major repair/rebuild
914World.com > The 914 Forums > 914World Garage
Mark Henry
Over the winter I'd like to repair my dad's canoe. I know it looks bad, but the main skin is kevlar, the woodwork is cedar and fairly simple, plus there is enough bits to copy. I have the tools, my trade is cabinetmaking. Only thing missing to copy is the yoke, but the old one sucked anyways

The kevlar repairs will be the only thing hard-ish to do and this is where the question comes in....
Can I cut this in half and add 3 feet to the center?

It's a 15-1/2' canoe and it's looking like I need a 3 person canoe. If the wife was into it I'd get another canoe, but if it's just me and the 2 kids I'd rather have just one canoe. Most 3 person canoes are 18-19 feet.

Any tips would be welcome smile.gif
Mike Bellis
Kevlar is almost like fiberglass and uses the same techniques. I would be a little concerned with the structural integrity after adding 3 feet..

That is probably a vacuum molded product. Very hard to duplicate in the garage. You could build a buck and layer it on old school style. It will not be as smooth or as thin but should work.

How concerned with looks are you?
914forme
QUOTE(kg6dxn @ Sep 20 2013, 05:10 PM) *

Kevlar is almost like fiberglass and uses the same techniques. I would be a little concerned with the structural integrity after adding 3 feet..

That is probably a vacuum molded product. Very hard to duplicate in the garage. You could build a buck and layer it on old school style. It will not be as smooth or as thin but should work.

How concerned with looks are you?


You can vacuum mold in your garage, and it is recommended with Kevlar to get the epoxy resin into the weave. BTW, Epoxy is nasty stuff. It will take a large bag, and a good pump.

I would lay it up on the inside then bridge the gap. Add structure to tie it all together, then spray new gel coat on the outside. Then spray wax on the outsdie of the gel coat. The wax will actually protect it and allow it to cure properly. You can then buff it out.

If you skip the wax, it will not cure for almost the entire season. Did a jetski once, and learned th hard way. headbang.gif Once it has cure you can buff it to a super gloss shine.

Option #2 is use the existing shell as a form, wax the shell and make it your plug. You could then make it out of carbon fiber use a clear gel coat, and have a ricer canoe. Just need a few stickers, and a fart can.
warpig
By the looks of that thing you might be better off getting one of the beach assualt landing crafts that the Marines use. idea.gif Seriously that thing is done.
Mark Henry


QUOTE(warpig @ Sep 20 2013, 09:30 PM) *

By the looks of that thing you might be better off getting one of the beach assualt landing crafts that the Marines use. idea.gif Seriously that thing is done.

I know it looks bad but the woodwork is the easy part, all pretty simple stuff. I would have to make forms for the ribs and a steam box for the bending, but it's not as hard as one may think. The material cost to repair the holes and wood (without the extension) would be only be a couple hundred dollars and 4-5 Sundays. I have most of the wood needed, just what ever the epoxy costs.

QUOTE(kg6dxn @ Sep 20 2013, 05:10 PM) *

Kevlar is almost like fiberglass and uses the same techniques. I would be a little concerned with the structural integrity after adding 3 feet..

That is probably a vacuum molded product. Very hard to duplicate in the garage. You could build a buck and layer it on old school style. It will not be as smooth or as thin but should work.

How concerned with looks are you?


I only care about function and that it's light. This canoe weighed 48 lbs. when new. The ribs give it the structure, the broken ribs why it looks so warped.
JRust
Only a 914 guy would rebuild that evilgrin.gif . Most sensible people would just buy another Canoe lol-2.gif

No insult meant. Always cool to learn new tricks. I just have a hard enough time working on my 914's. Let alone doing a project unrelated to them. Good luck I'll be watching to see how it turns out pray.gif
Mark Henry
QUOTE(JRust @ Sep 21 2013, 01:09 AM) *

Only a 914 guy would rebuild that evilgrin.gif . Most sensible people would just buy another Canoe lol-2.gif

No insult meant. Always cool to learn new tricks. I just have a hard enough time working on my 914's. Let alone doing a project unrelated to them. Good luck I'll be watching to see how it turns out pray.gif


Cheaper than a 914, Kevlar doesn't rust shades.gif

Something like this is plan B on the 3 man canoe, but I think I'd still rebuild dad's as well if I did this.
http://www.canoe-suwannee.com/cedar_strip_canoe.htm
balljoint
Rebuild it. Don't Frankenstein it and add to the middle. I don't think that would be safe.

This boat will be carrying everything you need to survive as well as your family.

Eastern cedar over western for strength and fibre length on your ribs.

PVC tubing can make a quick steam box.

I have done lots of fiberglass repairs. Never Kevlar.

I have plans to build a strip kayak and a Jon boat. Just no time at this point.
barefoot
Disagree with prior post. Epoxy is easy to work with, just make sure you use correct resin/hardener ratio, easy to do using WEST system pumps as they give correct mix.
Epoxy is stronger than polyesther and makes a stronger bond.
Kevlar is very hard to cut, I went thru several pairs of shears before finding one that would cut the stuff. Using kevlar is not necessary, you could use fiberglass or carbon cloth for the extension, just have to use a bit more thickness with the glass. It might be a good idea to incorporate a foam or balsa core in the new area, this will make the structure much stiffer than a single skin of either kevlar or glass. hardest part will be to make a form to get the proper shape. Suggest laying visiqueen plastic sheet over a good section of present hull and then lay-up new outer skin over this. it won't stick to the plastic and will be a good match to the form needed. then support it somehow and add more glass, carbon, or kevlar to the inside to get the thickness you want. Fair it into the old hull in at least a 12:1 ratio.
Forget gelcoat as it doesn't adhere well to epoxy, To get a smooth outer surface, using WEST lightweight 410 filler mixed into epoxy and trowel thin layer over skin using wide drywall spreader. This stuff will sand easily to get finish you want.
here's sample of epoxy/glass over foam core engine box i did for sailboat project
Click to view attachment
barefoot
r_towle
We built them high school with a mold, but no vacuum.

You will need to make a mold to get the middle shape correct, but it should work.

You will need to make a female mold, then lay the canoe right side up into the mold.

So the mold might be 5 or 6 feet long to help you line it up.
Use plywood bucks, and 1/4 inch plywood screwed into the bucks.
Then sand that, and lay two coats of fiberglass on the inside of that mold.
Sand, fill, paint with epoxy paint, but and wax that mold.

Then you lay everything together and mold you fiberglass on the inside while overlapping into both halves.

Let it set, and put your new gunnels in place, then relapse from the mold.
Then flip it over and finish the other side with new Kevlar to make the bottom smooth.

Rich
Mark Henry
QUOTE(barefoot @ Sep 21 2013, 09:48 AM) *

Disagree with prior post. Epoxy is easy to work with, just make sure you use correct resin/hardener ratio, easy to do using WEST system pumps as they give correct mix.
Epoxy is stronger than polyesther and makes a stronger bond.
Kevlar is very hard to cut, I went thru several pairs of shears before finding one that would cut the stuff. Using kevlar is not necessary, you could use fiberglass or carbon cloth for the extension, just have to use a bit more thickness with the glass. It might be a good idea to incorporate a foam or balsa core in the new area, this will make the structure much stiffer than a single skin of either kevlar or glass. hardest part will be to make a form to get the proper shape. Suggest laying visiqueen plastic sheet over a good section of present hull and then lay-up new outer skin over this. it won't stick to the plastic and will be a good match to the form needed. then support it somehow and add more glass, carbon, or kevlar to the inside to get the thickness you want. Fair it into the old hull in at least a 12:1 ratio.
Forget gelcoat as it doesn't adhere well to epoxy, To get a smooth outer surface, using WEST lightweight 410 filler mixed into epoxy and trowel thin layer over skin using wide drywall spreader. This stuff will sand easily to get finish you want.
here's sample of epoxy/glass over foam core engine box i did for sailboat project
Click to view attachment
barefoot


Excellent info barefoot

I have a local source for kevlar and west system products. Price doesn't seem too bad.
QUOTE
Forget gelcoat as it doesn't adhere well to epoxy

The finish on the canoe is not regular mold and gelcoat smooth, in fact I think it's just painted. If I power wash it hard (3000psi from 2-3 inches) I can blow off the paint/gelcoat...whatever it is, down to the gold colour kevlar. The kevlar may be just a single ply, it's only .055 thick.
Mark Henry
QUOTE(balljoint @ Sep 21 2013, 09:42 AM) *



Eastern cedar over western for strength and fibre length on your ribs.

PVC tubing can make a quick steam box.




I have lots of local cedar. The PVC pipe steam box is a good idea! And I just need a kettle for the steam.
r_towle
Wallpaper steamer rented does a great job.
Mark Henry
Man.....I should buy and finish this and just repair dads canoe confused24.gif idea.gif

I know that would mean I'd be solo in one canoe and it doubles all portages.....but most of the work is done.

http://peterborough.kijiji.ca/c-cars-vehic...QAdIdZ524952614
Mike Bellis
QUOTE(Mark Henry @ Sep 22 2013, 06:20 AM) *

Man.....I should buy and finish this and just repair dads canoe confused24.gif idea.gif

I know that would mean I'd be solo in one canoe and it doubles all portages.....but most of the work is done.

http://peterborough.kijiji.ca/c-cars-vehic...QAdIdZ524952614

Yes. Just repair it and buy another.

Although I'm not sure what a portage is exactly. Not a term used in California. I assume is the cost to put your boat in the water.
Mark Henry
QUOTE(kg6dxn @ Sep 22 2013, 12:24 PM) *

QUOTE(Mark Henry @ Sep 22 2013, 06:20 AM) *

Man.....I should buy and finish this and just repair dads canoe confused24.gif idea.gif

I know that would mean I'd be solo in one canoe and it doubles all portages.....but most of the work is done.

http://peterborough.kijiji.ca/c-cars-vehic...QAdIdZ524952614

Yes. Just repair it and buy another.

Although I'm not sure what a portage is exactly. Not a term used in California. I assume is the cost to put your boat in the water.


A portage is carrying your canoe and all your gear from one lake/river to another or around waterfalls, etc.
This is why you want a very light canoe, one person carries the canoe, the other person both backpacks. With a light canoe I'd rather carry the canoe.
Having to make two trips is a drag if the portage is a couple of km's.

If I had a 3 person I carry the canoe and the two kids carry all the gear. One trip.
r_towle
Part of training them for canoe camping is portage.
Two of them can carry a fiberglass canoe.

Get the cross bars for this task.
Mark Henry
QUOTE(r_towle @ Sep 22 2013, 08:06 PM) *

Part of training them for canoe camping is portage.
Two of them can carry a fiberglass canoe.

Get the cross bars for this task.


With a light canoe and a one man carry it is so much easier.
I could lift and carry dad's canoe since we got it, when I was about a 14yr/old.
You couldn't pay me to take a heavy (<80lbs) fiberglass canoe, even if it was new.

Why do you think I would go to the bother to rebuild this one????....
Ummm.... because it's kevlar and weighs >50 lbs
balljoint
You have your less than and greater than signs reversed.

My fibreglass canoe is an easy carry and will hold 1000 lbs. It only has two seats but...
JoeSharp
Mike: The Kern River requires portage.
Mark Henry
QUOTE(balljoint @ Sep 22 2013, 09:43 PM) *

You have your less than and greater than signs reversed.

My fibreglass canoe is an easy carry and will hold 1000 lbs. It only has two seats but...

Nope, new this canoe weighed in at 48lbs, I remember the builder saying it and we weighed it on bathroom scales.

I'm just going to repair it. You cut out the bad area and make several patches, each increases in size a bit. Sandblasting the patch area is the best prep for the Kevlar then I'll use West system epoxy. When totally done I'll epoxy paint it.
The forms for steam bending the ribs could be used for a cedar strip if I ever decide to make a 18 foot.

A new kevlar canoe is about $3K and I'm figuring >$300 (that's less than, right?), so definitely worth it.

As far as weight goes, Dave you've met me, my daughter is 14 and almost 6 foot and the boy is 12yrs, 130 lbs, 5'-6" and has grown an inch this summer alone. In a couple more years I bet people alone will be <600lbs in that canoe.
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.