What's up with my rails?

Howard Caplan

Wooden Canoe Maniac
I thought the darker color on my rails was from banging around but after sanding a few sections I am now wondering if it could be some kind of fungus or mold.
I built this canoe about 4 years ago.
It does seem to be on the sections of rail where hands and fingers tend to land - is this a clue.
The inwale is ash. The outwale which is where the splotches are is walnut.
What is the sealer you use on ash before varnish?

I am thinking my winter project may be to take the out wale off and give it a deep sanding and see what happens.

I'll try to take time this weekend to get a few pics and will post.

Thanks for the replies so far.

Perhaps trying a round of teak wash, oxalic acid, household bleach in that order of harshness? (maybe Oxalic acid and teak wash are equal I do not know). Might be easier and save more patina and material than deep sanding. Pictures?
A few pics of the discoloration on the walnut rails.

This is the first time I uploaded to this site in quite a while.



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My guess: It almost looks like residual left over varnish or oil that did not get stripped? Maybe try using a scraper to remove and then revarnish.
That's the result of water lifting the varnish, getting under it and inside of it and weathering the wood or growing some manner of fungus. Are you sure that's walnut? From what I see in the pictures, it looks a lot more like mahogany to me - and yes, it will weather like that in a situation where moisture is trapped against it.
Definitely walnut. Never been stripped, canoe built with new wood four years ago.
Water lifting the varnish sounds reasonable. And the worst if it is on the underside Where water could have settled under the cover all winter.
I would imagine cherry or mahogany would add some additional value to the canoe. OK it's very good quality mahogany.

Do you have any of the walnut left over that you could varnish and show us?

To my eye, (which admittedly hasn't seen much walnut) that looks very light to be walnut.
One of the guys in our crew uses it a lot on his canoes, and it's always very dark, and looks VERY nice.
If I didn't know better, I'd say that looks a lot like birch.

BTW, IMO ash should be avoided if possible on a canoe, at least one you don't want turning dark/black. :)

I have thought back four years and the out wales are black walnut. I have worked a bit with walnut and have seen a lot of variation. The decks on this canoe are also walnut but from a different plank and the decks are darker with a distinctive flow to the grain. The rails may have been edge wood which would be softer and lighter but still walnut.

I just returned from a camping trip on Rock Island, just off the Door County peninsula of NE Wisconsin. We take the ferry from the mainland to Washington Island, drive across Washington Island and then paddle the two miles to Rock Island. Friday morning we woke up to steady breeze that gathered force as the morning wore on and we packed up to go. Amy suggested we wait a bit to see if the wind dies down. This passage is NOT the infamous Deaths Door, there is a sand spit that separates Green Bay from Lake Michigan. The bay we paddle across is part of Green Bay and the water gets confused in a wind like we had. This modified Prospector has great stability especially when loaded and I never hesitated and told Amy I thought the wind would build all day and we would have to take the ferry which I didn't want to do. We were never in any danger even when we were going through 3 foot rollers but the wind was relentless and I found out later it was topping 30 - 35 MPH and we had to stay straight into it to maintain stability. The ranger who was watching us from shore, told us later he spotted us and 20 minutes later we were in the same spot. Took us 2 hours to make the 2 mile crossing but the canoe never wavered. Amy went through all the terror of the realization that if she relaxed in the bow for a moment we would lose ground or worse, lose our angle to the waves. She became convinced that I was just stirring tea in the stern - the classic bow/stern tension - and she was doing all the work. She didn't think she had the strength to complete the passage, but she did. Once we passed the first island, we gained a bit of relief from the wind and as we finally got closer to the harbor, the wind became a bit more controllable and the water began to flatten out. Then we saw the flash of lightening and heard the thunder too quick. Talk about motivation. She started powering like mad, while I stirred more tea in the stern.
She yelled back to me as the ferry passed that this was the 4th time we saw the hourly ferry cross. I said no it wasn't. She was correct, of course. Once landed and while unloading the ranger appeared to tell his side of the story. He said he was ready for the rescue as they have rescued 4 groups this year. He told me he got worried as I angled toward that first island as they can't get close to it because of the rocky shallows all around. I assured him I was just using the island to get some shelter and had no intention of getting too close in the shallows. Once the boat was unloaded and secure, I looked out at the passage and asked the ranger if it went flat. He said yes, the wind died down and it was perfectly flat now. I still say if we waited an hour it would have continued to build.
I also realize this is the only canoe I own that I would have attempted this. My royalex canoes would never have responded the way the w/c did and my choice will always be this canoe, no matter what the rails are made of.
Had the same problem with ash rails that had not fully dried before i fabricated them. After a few years i found this dark green to black fungus growing on the rails. I removed the varnish with a card scraper but the fugus left black stains on the wood. These did not respond to oxalic acid. I did not try Teak Nu but it might be worth a try. It's a two part product, the first being a weak lye solution and the second a weak phosphoric acid solution. Like oxalic acid it will not damage the wood. Household bleach would be a last resort and should be tried first on a small inconspicuous area as it will damage the wood fibers. Personally I gave up using the stuff for that reason. In my case I was never able to entirely eliminate the black stains as some had penetrated deep into the wood. The scraper did go a long way toward minimizing the problem. After cleaning the rails with the scraper I applied new varnish. That was this past Spring and so far so good. Good luck with your project.
Great story about the Rock Island crossing. I remember paddling to Rock Island with my then girlfriend for a weekend camp out back around 1984. We were like kings compared to the backpackers with our steaks and cooler. We too had the waves rolling in when it was time to go. I remember trying to launch into the teeth of it and having the surf throw us back. Kathy then had the inspired idea that if we carried our gear to the other side of the island and launched we'd be in the lee. Smart woman, glad I married her.
Glad to hear hear you've been there. You must of been on the L. Michigan side, camping.
Sounds like you made the right choice in marrying your girlfriend!