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Fiberglass

Discussion in 'Wood and Canvas' started by dcarey101, Jul 22, 2018.

  1. openboater

    openboater Curious about Wooden Canoes

    Just to add a little to the conversation, there is currently an Old Town Wood canvas/fiberglass on eBay. S/n 184256
    The ebay listing has a copy of the build record with the wood canvas scratched out and fiberglass written in. Also a pic of the catalog showing it as a ‘Trapper’ model with factory plastic coating. As it’s a 1969 canoe, am I correct in assuming it would have been polyester resin ? They are asking considerably more than $200

    https://www.ebay.com/itm/1970-Old-T...town+50+lb&_from=R40&rt=nc&_trksid=m570.l1313
     
    dcarey101 likes this.
  2. OP
    OP
    dcarey101

    dcarey101 Curious about Wooden Canoes

    Interesting-anyone have any input on when they switched from canvas to fiberglass? Why/
     
  3. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Yes the Trappers were polyester resin. We found that the clear finished ones sold pretty well, despite the fact that the typical wood/canvas canoe's planking pattern is nothing like you would see on a normal wooden boat. It must have been about 1970 or so when the Trapper showed up in the line. The Lightweight was the wood/canvas version of the 15' canoe, the Trapper was the fiberglass covered version and the Featherweight the Dacron covered version. Delamination on impact was, and still is, always the biggest danger for any polyester resin fiberglassing job on wooden hulls. It can then lead to pockets of trapped water between the skin and planking where the delam was. Trappers were not immune to this possibility, but they were expensive enough compared to the fiberglass, polyethylene, and Royalex Old Towns that most got babied.
     
    dcarey101 likes this.
  4. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Why? As someone who was an Old Town dealer beck then, you got the feeling that Old Town felt that the glass covering was going to be the future for wooden canoes and eventually replace canvas as the stock covering. Advantages, like the fact that the production time would no longer require long periods of canvas filler drying was one benefit. At the time though, fiberglass technology, especially when blended with wood, simply wasn't up to the task. I remember at one point eavesdropping on a telephone conversation between Jim Smith, the owner of The Sportsman's Center in Champaign, Illinois and Dean Gray, the head honcho of Old Town at the time regarding a delamination bubble about 2" in diameter on the bottom of a brand new, clear finished Trapper. Mr. Gray was telling him that the bubble didn't exist, yet we were standing right there looking at it. The topic then became one of what would be done to remedy the situation, as it was not an easy fix. I eventually bought Smith's inventory and took over the dealership, but luckily that one had been taken care of, one way or another by then, so it wasn't my problem.
     
  5. Dutch

    Dutch New Member

    A question was asked earlier as to what color Todd's OT is. I too fell in lust with it the first time I saw a picture of it. I wanted to try rolling a paint job, as there are no decent brands of spray left, so thought I would give it a try on a 12' American Fiberlite I came up with. If it turned out bad it was no big deal. I trust Rustoleum's oil based paint so I bought a can of the only yellow they make (they use to make a lighter lemon yellow, but discontinued it). With the first roller full it was "Yeah, right. This would be fine if I was painting a school bus". Since I had already started I finished the first coat with it to have an even base. The search for a decent yellow was resumed with no luck. I finally mixed a can of gloss white with the 1/2 can of yellow I had left. It's not the exact same shade as Todd's, but it's close. New Fiber Lite 12 - 1.JPG
     
  6. Dan Lindberg

    Dan Lindberg Ex Wood Hoarder

    I wasn't thinking the leftover material,
    I was thinking where it is mixed wrong and "kicks off" and gets so hot you can't hold it any longer, and the whole batch is hard in minutes.


    "The leftover hardened resin disk in the mixing cup that pops out and often resembles a hockey puck is officially know as a "round to-it"."
     
  7. Todd Bradshaw

    Todd Bradshaw Sailmaker

    Since epoxy is mixed at a specific resin/hardener ratio which is the same for all applications, concentrated amounts of it will heat up, but usually not to the point of damaging anything - although you probably don't want to hold the cup through the hardening process. What can make a big difference though is the addition of certain fillers, like microballoons, which due to their hollow, air-filled nature tend to insulate, trapping heat. The cup containing a concentrated mass of these fillers can heat up to the point where it is smoking.

    Polyester resin is a different story. It will contain a promoter (often some sort of cobalt compound, which gives the resin a slightly blue tint, though there are a variety of other promoters). The MEKP liquid hardener oxidizes the promoter in the resin, generating heat and the heat hardens the resin. A thin layer, like you would apply when sticking down a layer of fiberglass might do well with maybe ten to twelve drops of hardener per ounce of resin - giving adequate working time and a fairly quick cure. Gelcoat might need nearly double that, as it will tend to peel as it hardens if it cures too slowly. A thick casting of the same resin could be done with much less hardener added (maybe four drops per ounce, although ambient temperature also figures into all of these). The reason is that the heat is concentrated in the thick casting's limited surface area. The thin layers, like the fiberglass, take more hardener because the resin is spread out over much more area and dissipating the heat the hardener and promoter are generating.

    If you have a fair amount of leftover polyester resin in the cup after applying a thin layer like fiberglass or a filler coat, and it was mixed with a lot of hardener, it will really heat up big time. It may smoke, it may crack the hockey puck as it hardens and it can even catch fire.

    The yellow color on my Guide is Ace Hardware polyurethane floor enamel, rolled and tipped. I just looked through the color cards until I found one that was kind of a soft shade and had them mix it for me. It has a bit more orange peel texture than some of the expensive marine enamels, but not bad and not very expensive. Another good and reasonably priced custom color offering is Home Depot's "One-Part Concrete and Garage Floor Enamel". I used it for the base color coats on my fur trade stripper canoe. The base was rolled and tipped and the shading was sprayed, the grain lines were applied with a grooved roller I made, and then the flat finish top coat was Enduro Pre-Cat conversion varnish which I sprayed. You can buy a custom mixed gallon of these sorts of enamels for about what a quart of the premium marine enamels cost.

    lau3.jpg
     
    monkitoucher likes this.
  8. Dan Lindberg

    Dan Lindberg Ex Wood Hoarder

    Well, I can attest to it getting very hot and kicking off and I can only assume it was mixed wrong. Meaning I must of forgot the number of strokes I put on the pump when filling the cups. I only mix 6 oz batches so not a lot was lost. This was with either MAS or System 3 Clear Coat.

    PS - I've never worked with polyester, only non-blushing epoxy

    "Since epoxy is mixed at a specific resin/hardener ratio which is the same for all applications, concentrated amounts of it will heat up, but usually not to the point of damaging anything"
     

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