Wooden gunwale replacement..dimensions?

so i picked up a neglected kevlar mad river winooski canoe at an estate sale for 20 bucks. what can go wrong for that price right? plus my wife cant complain about another canoe if i only paid 20 dollars. the hull looks to be in pretty good shape, although its pretty dirty. The gunwales are completely gone. nothing but the screws where left. the seats are still usable along with the thwart and yoke. i looked at northwest canoe and eds canoe for the replacement gunwale. naturally i really dont want to spend that much on them. i have seen some stuff online for sizes - inner gunwale at 1 inch by 3/4 inch and the outer at 5/8 inch and 3/4 inch wide. i am in the metro atlanta area. so if you know any wood working shops or better yet dimensions for a homemade gunwale please let me know. I would prefer to use ash. the hull i am going to really get at clean this weekend. if the gel coat is in good enough shape i may just use a few coats of bristols amber to get it to shine. any suggestions are greatly appreciated. Thanks Rick

gunwale dimensions
I think the dimensions you listed are good. I have seen rails on boats with dimensions as large as 1" X 1", usually whitewater boats. You can get by with a little smaller.

If you are going to drill holes in the inwales for the thwarts and seats (the usual method) you really don’t want to go with inwales less than 3/4" wide IMO, so as to avoid weakening the wood too much with the #10 size holes.

I agree that ash is probably the best wood to use, but unless you are very fortunate, I doubt you will beat the price of Ed’s knock down system, at the end of the day.

You will need to find a source that is within a radius you are willing to drive to and back as shipping gunwales is just prohibitively expensive. Used to be, if you bought replacement gunwales from the manufacturer, they would ship them to a dealer if and when that dealer was receiving a canoe order. Don’t know if that still applies but you would have to buy from Mad River and find a nearby dealer and then wait.

To redo your boat you will need sticks 14 1/2 feet long, or you will need to join shorter lengths together with scarf joints, or the modified shiplap joints Ed uses. You need to decide on a few other things as well.

Most composite canoes have 2 piece gunwales (inwale and outwale) in which either the inwale or outwale is rabbeted so that a thin kerf extends over the top of the hull and hides it. It is better to rabbet the outwale IMO to preserve the full width of the inwale for your mounting holes. It is not necessary to rabbet the rails, you can simply sandwich the rails and hull top together so that all three are flush, but you might find you need to smooth up the hull top with a sander first.

You might also choose to have the outwales radiused which saves a little weight. Some folks like having slotted or scuppered inwales. If you want the wood radiused, rabbeted, or scuppered make sure you find a mill that will do this for you, or find a woodworking friend with a shaping table.

What about the deck plates? Mad River used pretty nice inset deck plates on most of their composite boats. My guess is if the gunwales are toast, so are the deck plates but sometimes it is possible to salvage a pair of deck plates and reuse them but it involves considerable work. You could make so onset deck plates out of some relatively thin wood, or you could simply go without.

This pdf from Mad River gives instructions for rerailing a canoe including how to fit inset deck plates and is probably worth reading:


In addition to the cost of your wood remember you will have to budget for deck plates (if necessary and if you choose), finish for the wood, and 55-60 stainless steel screws (unless the existing screws are usable) as well as clamps, sandpaper and sundries.

If you are looking for a low cost alternative you could look into using pine. A recent thread discussed this:


Yes the deck plates are shot too. I was thinking of using some red oak that i have laying around and instead of mounting them flush i would just overlap and screw them from the top down to the gunwale.

“Most composite canoes have 2 piece gunwales (inwale and outwale) in which either the inwale or outwale is rabbeted so that a thin kerf extends over the top of the hull and hides it.” are ed’s rabbeted, i was wondering how they do that? i was thinking i could rabbet the outer on the router. thankfully my coworker does waterfowl decoys and has a table saw, planner, and router. could you sandwich the composite but leave maybe a 1/4 or 1/8 and use a marine wood filler? I found Peach State lumber near my house and they have ash so i am going to by tomorrow and see what they got.


– Last Updated: Oct-03-14 9:40 AM EST –

For your gunwales you will want to look for wood with the straightest possible grain to minimize grain "runout" which weakens the gunwales, increases the likelihood of splitting, and presents open end grain for water to penetrate and rot the wood. You also want wood with no knots, or as few as possible.

You want fairly thin kerfs on your rabbeted outwales. Too thin a kerf is likely to break off. But too thick is not good either. If you used outwales which were 3/4" tall (a common dimension) and rabbeted a kerf that was 1/4" thick you would leave only 1/2 inch of the top of the hull covered by your rails. That is a small target to hit when drilling pilot holes for your wood screws, and leaves the holes very close to the hull top, if not through the hull top. So you don't want the lip or kerf any thicker than 1/8".

You will probably find that the thickness of the composite hull varies a bit. They are often thicker at the stems and often in the center or where seats are mounted, and thinner elsewhere. You want your rabbet deep enough so that the lip or kerf covers the thickest parts of the hull. The kerf might be a bit too long in some areas, but the wood will squeeze down a bit as you clamp and screw it so it won't be a problem.

The wood can be rabbeted using a table saw with a dado blade, or even a regular blade by making multiple passes. Or a router mounted on a good quality table. Because of the length of the wood pieces, it is often good to have 2, or even three people available to handle the ends to minimize the chance of breakage. Your friend can probably offer you better advice than I can. You can find a ton of tutorial videos on how to cut rabbets on a table saw or shaper table if you want to check it out further.

If you don't want to go to the trouble of rabbeting the rails I would just sandwich them. This is how wood rails are mounted on nearly all Royalex boats and it looks fine as long as the hull top is sanded flush. It is also stronger because for the same height of inwale and outwale, more of the hull top is covered and the screw holes wind up being further from the hull edge.

Using capped decks will simplify things quite a bit. With inset decks you have to carefully shape the ends of the inwales to fit flush inside the curvature of the hull stem, and so they join with each other flush down the center line of the canoe. Then you have to shape the deck plate blank so that it fits flush into the inwales. With capped decks the ends of the inwales are covered so they can stop a bit short of the end of the hull and need not join together. Make your deck caps wide enough so that they just cover over the joint between the inwales and the outwales, and screw them down onto the inwales with stainless or brass hardware. Wait till you have your rails, thwarts, and seats reinstalled and you can cut out a deck plate template from stiff cardboard.

Some composite hulls will collapse inward a bit, or sometimes the other way, when the rails and thwarts are removed. When you go to mount your rails, check the beam of the canoe. You may need to use a spacer stick to bring the boat out to its correct beam (39" at the molded hull) as you start to mount your rails.

Before you mount your rails make sure that the hidden surfaces of the inwales and outwales that will be against the hull are well-treated. You might just use penetrating oil, but I like to use epoxy or varnish or both on these surfaces, even if I am going to oil the visible surfaces. You will probably find it easier to drill all the pilot holes for your screws through the inwales, and counter sink them, before mounting the rails. The last three or four screws on each side at each stem will have to come in from the outwales to the inwales since there won't be room enough to get a screwdriver inside the hull.

I don't know if Ed's gunwales are rabbeted. He or his wife usually answer the phone, or return a call promptly if you leave a message so you can easily ask. If they are not, and you want the outwales rabbeted he may have the facility to do that for you. I have not used Ed's knockdown gunwale system. I have heard that quite a few like it, but I know of a couple that said that the modified shiplap joints resulted in "flat" areas along the sheer line of the canoe.

I would say that if you can find decent ash locally and have a friend with woodworking expertise you might be able to do better going that route.

With Ed’s, is the entire gunwale glued
together before installation? My old Moore needs gunwales, but most of the sheer line is fairly level, followed by strong upward bends near the 18.5 foot length.

If the ship joints create flats, would they resist the upward bend? Could I take advantage of the nature of the joints and slightly tweak in a bit of bend?

Might depend in part on how far the last (bowmost, sternmost) joints are relative to the ends of the boat.

new wood rails
lengths can be hard to get. When I can not, this is what I do. A good scarf joint ratio is 8:1. I make up a sled that rides the miter slot groove in my table saw. This sled has a fence at the 8:1 angle. I clamp my stock to that fence and slide both pieces through the blade. (Please don’t saw any clamps.) Then I make a clamping jig, 2 waxed surfaces at 90 degrees, to register the joint. I use type III glue, clamp in the jig over night with waxed cauls, clean up in the am. strong, long, and straight.

1:8 is about the minimum scarf to get two screws through the scarf and hull into the outwale using 6" centers. In a perfect world we would prefer to offset the scarfs on the hull, say, inwale scarfs 9" forward of center, outwale scarfs 9" aft for those who enjoy symmetry.