Maintenance of wood trim for canoeistsThe reason we have to oil or paint wood, is to prevent wood from getting wet. When wood is wet, it will not only rot away in time, but it is considerably weaker too. Since wood gunwales and thwarts can be seen as the backbone of the canoe, it is important that they are strong and rigid enough to preserve the shape of the canoe well.Painting versus oilingThe difference between painting and oiling is that paint creates a more protecting finish on the surface of the wood. Epoxy (paint) is perhaps the most waterproof in that respect. Oiling adds some water resistance in the wood but, especially on the surface, can wear of quite easily.Which woods to oilThe best use of oils is on so called hard woods. Hard woods like cherry, mahogany and walnut already have a high resistance to rot themselves and they do not absorb high amounts of oil like soft woods can do. The high absorbency of oil makes those soft woods heavy, thereby offsetting the advantage of using soft wood in the first place.Which protection for what kind of canoeFor a quite rigid boat like a wood stripper canoe, the gunwales can probably best be epoxied to the hull and totally covered in epoxy and then painted, along with the rest of the boat, with a two part polyurethane varnish containing a good UV filter.For a Wood & Canvas canoe you can either use oil or paint the gunwales with an oil based varnish. It all depends on your own maintenance preferences, that you really will have to establish when you own such a boat! If the inwales are made from soft woods (as sometimes is the case) you should preferably use varnish. For Fiber Reinforced Plastic and Royalex canoes, oiling the gunwales could be best, as the flexibility of these kind of boats may cause paint on gunwales crack too easily over time and let water in. And for many people oiling frequently is easier than painting regularly... The culpritThe problem with wood gunwales, especially when your canoe is stored outdoors, is not so much the outside of the rails, which can be easily maintained with oil, but it is the part of the gunwales against the hull, where water can collect gradually and cause rot from the inside out. A thorough oil treatment of the inside of the gunwales, how inconvenient that may be, is possibly the best prevention against rot. If that kind of maintenance is unpractical for you, the best thing to do is choose aluminum or vinyl/aluminum gunwales on your canoe.Linseed oilThe oil commonly used for wood preservation is boiled linseed oil. Boiled linseed oil is not really boiled, but has additives which makes it dry better than 'raw' linseed oil, acting like it was heat treated. Raw linseed oil will take a very long time to dry -- weeks in fact -- and still never fully cures. However, raw linseed oil impregnates better into bare wood than boiled linseed oil, and because raw linseed oil dries so slowly, you can leave it on for days for maximum impregnation.MildewBecause linseed oil is a vegetable oil, it may get black mildew spots when used in wet conditions. Especially when not fully cured, linseed oil is vulnerable for mildew. While that mildew may not be really harmful for the wood, it sure doesn't look nice. To prevent mildew and rot you can add wood preservative to the oil, but that can hamper the the impregnation and functionality. For that reason I do not add preservatives, but mix boiled linseed oil with about 24% tung oil, because tung oil is a little more waterproof and mildew resistant than linseed oil. Also I prefer to oil wood when temperatures are high and humidity is low. This allows the oil to impregnate and cure faster and better.Proprietary oilsMany people use proprietary oils for their wood maintenance, like those from Watco or Owatrol/Deks Olje or some kind of marine grade teak oil. These oils are often a mix of linseed oil, tung oil, resins, thinner, solvents, or whatever. They can work very well indeed, but I just happen to prefer to use the involved ingredients separately and judiciously.Modern VarnishTwo part polyurethane varnishes are very expensive, but should be more durable than oil based varnishes when used on quite rigid wood constructions, especially when these are treated with epoxy first. On my laminated wood paddles, two part polyurethane varnishes have been doing quite well. Also my own epoxy coats over paddle blade surfaces and/or edges do very well. I have even successfully used epoxy over oiled wood, after cleaning it very well with thinner. But I wouldn't recommend this as a usual practice, because I think the performance of epoxy in/on bare wood is much better.How I oil woodIf the wood has never been oiled before, I wet sand it first so that pores will be more open too. Then I clean and let the wood dry. When dry, I lightly sand the raised wood grain, clean it up and generously apply raw linseed oil and let it soak in for at least 24 ours in a as warm and dry a situation as possible. As long as the wood absorbs the oil, I add more raw linseed oil. When the wood doesn't absorb any more oil, I leave it for at least a day or two in a warm environment. Then I use #0000 grade (polish) steel or bronze wool to smooth the surface. After that, I wipe of all oil and debris from the surface and put on a light coat of a mix of boiled linseed oil and tung oil.Boiled linseed oil and tung oil will dry in a day or two, but it can take about 30 days for these oils to fully cure -- under good conditions. A working temperature of at least 20 degree Celsius is required for linseed and tung oil to 'cure' properly, with less than 60% air humidity and plenty of fresh air available, as linseed and tung oil cures with the intake of oxygen. The intake of oxygen is the main reason that these oils expand a little when curing, and therefore you should not leave a layer of drying oil left on the surface as it will only gum up when dry. Upkeep of oiled woodWhen used intensive and/or stored outside, the wood trim of a canoe, especially the gunwales, should be oiled a couple of times a year to preserve it well. Clean well and re-sand roughened spots and re-oil. Touch-up of worn spots can be treated with oil when they occur (preferably). Even damaged painted wood can be treated that way as a temporary measure against rot -- do clean it well before painting though!Oiling a wood paddleAn oil finish is relatively soft and not really waterproof, therefore oiled wood will absorb water in wet conditions and will wear of relatively easily too. So if you paddle a lot, you will have to re-oil an oiled paddle frequently, especially if you want to prevent warping or splitting of the paddle blade. Fortunately, oiling a paddle is easier to do than painting -- just sand the surface a bit if needed and apply oil.Because the warping of one piece wood paddle blades can be a serious problem, even when they are oiled well, there are many people who prefer to paint the blade and only oil the shaft and grip.
Cane seat maintenanceMost cane seats are painted, and should be maintained as such,but the underside of the cane can be best maintained with oil. |