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New member restoration question

Discussion in 'Wood and Canvas' started by sander63*, Jul 12, 2019.

  1. sander63*

    sander63* Curious about Wooden Canoes

    I am starting on my 1938 17 HW Old Town Sponson and while getting ready to strip and removing the thwarts, and noticed the center had bowed out about an inch. Will I be able to pull it back together with out damage? Also here is a picture of a little tool I made from a 7/16 hex socket to remove the diamond head bolts after pushing them back. Thanks to the WCHA members for all the help/encouragement!
    Tom 127468-17cc.jpg
     
  2. mccloud

    mccloud Wooden Canoe Maniac

    Welcome. You say bowed out? You mean the thwart is crooked, or the gunwales sprung out when you removed the thwart, or there is crookedness in the gunwale? I assume the outwale is already off? What I can tell you is that the center thwart on my 1939 OT, CS, HW is 32 inches - sig on the left. There is a chance these two canoes were built over the same mold. If the gunwales have sprung out when you removed the thwart, yes they can be pulled in again. Most of us install temporary thwarts, maybe just 1"x3/4" pine board, while stripping, etc. which helps the hull hold its shape. We like pictures here. Continue to post as you begin your restoration. Tom McCloud
     
  3. monkitoucher

    monkitoucher Canoe Curious

    I've used cargo straps at the thwart locations to keep it all together. Also, bar clamps in a pinch.
     
  4. dtdcanoes

    dtdcanoes LOVES Wooden Canoes

    Well, I cannot prove it but I have always sensed that when the hull is soaked up ( and I use hot water to flush the GOO ) a strap around the hull would want to round it it out...a cockle shell, if you will. A temporary thwart will tend to pressure the bilge more or less depending upon the character of the ribs at that point....I think. In any event, I wouldn't want to have made a mistake of this sort if it could be avoided.
     
  5. MGC

    MGC Paddlephile

    Yes.
    You will not have any trouble pulling it back into shape once you are already to. I've worked on boats that had been left without decks and thwarts for years that pulled back just fine. As long as you don't let the decks pull apart you should not run into any trouble. If the decks are pulling you should plan to remove them and plug the screw holes before replacing them.
    When you eventually replace the thwarts make sure that the thwart holes are not elongated or misshapen.... if they are, plug them and re-drill them so that they control the correct location of the rails when you re-install them. The same is true for the drilled holes in the rails.
    If you were working on a PeterNut you might be wondering if the thwart is too short or what width the hull should really be. For some reason getting the lines right on those is a juggling act.
    As a precaution it is (as has been suggested) a good idea to hold the hull from spreading.
    Interesting tool idea.
     
  6. OP
    OP
    sander63*

    sander63* Curious about Wooden Canoes

    It does not appear that the thwarts or seats have ever been out before, holes are not elongated all original hardware . I did remove the outwale and sponson rub rail on the starboard side to have a look underneath but thinking about putting them back on until done stripping etc. to avoid accidental damage. The family history indicates that it was stored indoors for decades and the wood while solid, seems pretty dry. Maybe oil after stripping? As suggested I made up a temporary pine thwart just to hold things in place for now. Thanks for the help!



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  7. Greg Nolan

    Greg Nolan enthusiast

    "Dry" is an ambiguous term with respect to wood. When green wood is seasoned by air or kiln drying, water is lost. Over time, the moisture of wood will seek equilibrium with the moisture (humidity) of the atmosphere. The average atmosphere indoors in most places is drier than out-doors -- because of heating and air conditioning. So canoes stored indoors for extended periods of time will generally be drier than those stored outside and paddled regularly. As wood loses moisture, it shrinks a bit and becomes less flexible.

    Putting your canoe in a pond, or leaving it out in the rain, will rapidly increase the moisture (water) content and flexibility of the wood of your canoe; leaving it out doors will more slowly accomplish much the same thing.

    Putting any oil on wood will do little, if anything, to change the moisture content of wood. except, perhaps to slow any change in the moisture content of wood as it adapts to reflect the humidity of ambient air.

    However, wood can have natural oils -- real turpentine is obtained from pine; teak and some other tropical woods are very oily and so they resist water intrusion and moisture-induced rot, and cedar, like most conifers, has some amount of sap which has, I believe, oily components which, over long periods of time, can diminish, and this can contribute to the wood seeming to be "dry."

    Some folks apply a drying oil to the outside of the hull of old cedar canoes to counter this. Some folks prefer to use a coat of thinned varnish (which traditionally is based on a drying oil). Some folks don't apply anything. Drying oils such as linseed or tung oil do not really "dry" -- they chemically cure and become more-or-less dry to the touch. Using linseed oil (boiled or otherwise) can lead to the wood turning very dark. Tung oil will not likely turn dark, but it is more costly than linseed oil. Using a drying oil will make the wood seem less dry and will add a slight bit of weight to the canoe. And it will slow the absorption of water and the resultant increase in weight that occurs when the canoe is put in water and used; so will applying a coat of (thinned) varnish to the hull exterior. Some folks think this is unnecessary, noting that most canoe builders did not, and still today generally do not, oil the outside of a hull.
     
    1905Gerrish likes this.
  8. mccloud

    mccloud Wooden Canoe Maniac

    What Greg said, with one addition: if you decide to oil the hull, don't do it until all the wood repair and fairing is done. Although oiled wood can be sanded, your sandpaper will fill very quickly. You might be surprised at how readily the old wood will suck up a turpentine/linseed oil mix slathered liberally onto it. Tom McCloud
     
  9. dtdcanoes

    dtdcanoes LOVES Wooden Canoes

    Lots of ways to skin a cat....oil when restoring ? For me the last chore before canvas goes on is the oiling of the interior and exterior surfaces. I take the time to carefully review the outside hull for all those things that cannot be done after the canvas is on. The interior is reviewed similarly. I oil the interior first with a VERY liberal coat RAW linseed cut with turp some 20-30 percent. Where it soaks in completely, add more. I check in a few hours for excess and wipe away. The hull is overturned after a couple days and coated not so liberally with BOILED linseed also cut with turp. Excess is attended to sooner than with RAW oil as it will begin to cure and not fun to wipe away and depending on plank gaps you may get some excess moving into the interior . ...the hull is righted and it is easy enough to wipe away any of the darker intruded boiled linseed. This Raw linseed will add a beautiful tone immediately and will not darken over time. The material will be absorbed completely in a few days and I have found the surface ready to accept the 1st thinned coat of varnish in 10 das. to 2 weeks. ( you will know with this test...hold and push down on your thumb nail to a rib surface midway on the hull. Drag your nail across the surface toward you a few inches and check your nail for a ridge of oil . You will get some early on and less as the days pass until there will be none. The surface will later feel and look dry, but it has simply been fully absorbed. ) This RAW material will not really cure as the boiled material does and remains green, though now incorporated in the wood structure.

    The plank and rib surfaces will now be ready for final staining efforts to match the original ribs. You should have treated some scrap rib and plank stock this way as well, to do trial stain work before applying to the new wood. And you would be able as well to put a first coat on an old rib that would represent the real new finish. I have never had an adhesion problem with new varnish properly applied and have never experienced the undesirable darkening some have had to accept. If the stripping was done well this new finish will have beautiful color and tone that will only improve over time.
    I may have to start another canoe....have fun
     
    1905Gerrish likes this.
  10. OP
    OP
    sander63*

    sander63* Curious about Wooden Canoes

    Thanks everyone for your thoughtful, detailed and very informative comments regarding my wood question. I remember years ago seeing people with the garden hose soaking their hulls before Spring launch time. It will be interesting to see what things look like when I get the varnish and house paint(?) removed from the interior.
     

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