Canvas covered kayak restoration

Discussion in 'Wooden Boat Building and Restoration' started by buzzman, May 23, 2011.

  1. buzzman
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    buzzman Senior Member

    HI, all
    As a complete newby to boat restoration I am seeking advice as to the best method of providing additional abrasion resistance and waterproofing qualities to a cedar strip and canvas kayak I purchased recently.

    The kayak was built in the 1970's and has had little use. I have not dunked it but the seller affirmed it floats and is watertight - at present.

    But I will be paddling in water with drowned trees and occasional rocks and would like to iprove on the abrasion and waterproof qualities of the kayak.

    My research thus far indicates that epoxy resin may not be a good isea, as it is apparently quite inflexible, and the canvas skin of the kayak i quite flexible.

    Would poluerethane be an option, or is ther some better product I have not come across?

    I also want to change the colour (it's currently an off-white, with years of accumulated dirt on top of whatever coating is on the originally gree canvas -it's unpainted inside and canvas is green coloured).

    Would I be better off (provided it is already watertight) of just repainting it or recoating it with some kind of coloured paint-like coating, and if so, what?

    Sorry, there's a lot of questions there, but maybe the answer is simple. :)

    Cheers
     
  2. gonzo
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    gonzo Senior Member

    Considering its age, the paint is an alkyd. That is regular oil based paint.
     
  3. buzzman
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    buzzman Senior Member

    Which coating?

    Thanks, Gonzo, I had already guessed what the existing coating was.

    My question(s) were more to do with improving on what's there and I'm seeking advice as to particular type of brand of finsih that would act like paint (in that it could be coloured or tinted) yet provide greater avbrasion and water-proofing qualities.

    Or if it would be better to use two products, what do you recommend?
     
  4. Lurvio
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    Lurvio Mad scientist

    I think you'll be hard pressed to get a canvas skin more resistant against rocks and such. I would think that a canvas kayak is meant to stay on clear waters.

    Lurvio
     
  5. cthippo
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    cthippo Senior Member

    Not necessarily. I've seen video of people hitting SOF kayaks with either end of a claw hammers and not penetrating. Depending on the fabric they can be very durable.

     
  6. PAR
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    PAR Yacht Designer/Builder

    Epoxy is the logical choice, though not regular laminating formulations. Call up the West System tech support folks and ask about G-Flex for this application.
     
  7. buzzman
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    buzzman Senior Member

    Will do! And many thanks for the tip.
     
  8. rwatson
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    rwatson Senior Member

    Epoxy by itself, even Gflex, wouldnt be my choice. For a start, being applied to paint means it has little solid adhesion, combined with the inherant flex.

    I am sure you would see it separating and holding moisture in it quite quickly, and cracking and sloughing off in short course. You would get better results by using a lightweight FG cloth with the epoxy, but separation from the original fabric would make wet voids.

    That previous video shows the common use of Ballistic Nylon impregnated with a Poly ... something. I saw a few examples at the recent boatshow. It is indeed super tough.
     
  9. buzzman
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    buzzman Senior Member

    Yeah, sure Ballistixc nylon is super tuff. What I have is 50 year old canvas painted with ordinary house paint.

    What product can I use to A) provide a bit betteer water penetration protection, and B) a bit better abrasion resistance, and C) something that I can change the colour with or go over with a differnt 'paint' coating to change the colour.

    Sales people tell you what they have on the shelf is what you need. Bull ****.

    That's why I'm asking here. What is the best thing for me to use?
     
  10. rwatson
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    rwatson Senior Member

    Well, the real answer to get more tough physical protection is to replace the covering totally with something like a tough nylon.

    Other than that, to just waterproof the thing really well, you need a really flexible paint. I have seen rubberised grey paint that they use on RIB boats and foldable canoes. If you peel a bit of the dried stuff off your skin, it actually will bend and stretch like rubber. However, it did eventually peel off the canvas as well, and let in water.

    The only really effective stuff I have seen work on canvas are some of the manufactured 'tar' products. Here in Aus, we have 'Brushable Hydroseal'. Its very thick and waterproof, but unfortunately it comes in 'not very smooth' tarry black finish.Its mostly used to waterproof water containers, and stays flexible for years. It adheres to even wet surfaces, and is impossible to even scrape off.

    You can then paint it with one of the standard marine enamels for a better appearance. That top coat will eventually crack, but the underneath layer will keep the insides totally dry. You can just touch up any damage periodically.

    I havent tried it, but I bet if you got some tough nylon and applied it over something like the Hydroseal on say, the bottom of the boat, while it was still wet, it would form a really tough and durable rock/stick protection layer.
     
  11. buzzman
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    buzzman Senior Member

    Yeah, someone else suggested 'tar like' substance, but as a chippy I have horror memories of using Ormonoid products on roofs and as a waterproof sealer....

    Is it as horribly balck and sticky as Ormonoid? Because that you sure as heck could not pain over, nothing would stick to it for long.

    I'm in Oz too. NSW. So who makes this 'Brushable Hydroseal' and can I get it at the big green shed, or is is a specialist only product and priced accordingly?
     
  12. gonzo
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    gonzo Senior Member

    All the canvas on frame boats of that vintage I know of use regular alkyd paint or linseed oil base. Either one can be cover with hardware store gloss alkyd. It is really easy to touch up and will not add a huge amount of weight. You have a boat that has survived a long time as it is. Fixing and improving something that works so well is a bad idea.
     
  13. buzzman
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    buzzman Senior Member

    So what you're saying is I shouod just over-coat it with the same stuff that's on there? Ordinary oil-based house paint?
    That works for me, as it's way cheaper than marine paints!
    I'm all for KISS principle, I just wasn't sure if re-coating with the same stuff was appropriate. Seems it is, so that's cool by me. Thanks Gonzo, made my decisions WAY easier! :)
     
  14. rwatson
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    rwatson Senior Member

    Brushable (dont get the non-burshable) Hydroseal is available in most decent hardware shops. It might be worth buying a small pot to start with.

    It can be applied and used straight away even in water. If you hit a rock, you could sew the canvas on the spot with some fishing line, dab a bit of goo on, and keep paddling. I know we had to on one trip.
     
    Last edited: May 25, 2011

  15. buzzman
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    buzzman Senior Member

    Ok, cheers
    I'll go check it out.
     
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