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Outline of planks showing through shellac

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I reapplied shellac to my White Guide last winter. I used what Jerry Stelmock recommended and it went well and looked great. It doesn’t seem to be holding up as well as the original but I’m assuming it is because this is the first season the boat was outside during the summer. Previous seasons I didn’t take the boat out until late September and the again in the spring so it wasn’t exposed to as much intense sun. Recently I noticed the shellac getting thin and chalky but wasn’t concerned because I can just reapply. What does concern me is that I can see the outline of the planks. This didn’t happen when the shellac was even thinner before I redid it last winter. Does anyone have any thoughts on why this is. The hull still seems fair with no noticeable cupping of the planks. 081EEA58-4B3C-460A-9EAE-E9F07EBA3A20.jpeg081EEA58-4B3C-460A-9EAE-E9F07EBA3A20.jpeg
 
Did you re-varnish the inside of the hull recently? Varnish can seep through the gaps in planking and show up like that.

Fitz
 
I was surprised how white and chalky the shellac has gotten. Did you use orange, waxed shellac? Typically, I re-shellac when the color is still brown/tan but thin. I have not noticed the planking showing through as in your picture. How many coats of shellac did you use? I also allow 8plus hours between coats after having some bubble issues from putting on too many coats too fast (on advice from the shellac guy at shellac.com) My canoes are stored under cover between uses and therefore I re-shellac about once every two years. Yours may be used more often than mine and be exposed to the sun more. Have you asked Jerry or Rollin?
Mark Z
 
Did you use orange, waxed shellac?

I was just reading the other day in the WCHA forums about the different types of shellac for canoe bottoms—orange, amber, clear, waxed, unwaxed, flakes. As I recall, the most expert advice seemed to be to use what Mark Z just mentioned, waxed orange shellac. Some other kind turned chalky white.
 
Thanks for the replies..
I think you just explained it Al. With the planks taking on some moisture they are stating to show their edges.
Jim
I did not know they did that, but it makes sense.

I was surprised how white and chalky the shellac has gotten. Did you use orange, waxed shellac? Typically, I re-shellac when the color is still brown/tan but thin. I have not noticed the planking showing through as in your picture. How many coats of shellac did you use? I also allow 8plus hours between coats after having some bubble issues from putting on too many coats too fast (on advice from the shellac guy at shellac.com) My canoes are stored under cover between uses and therefore I re-shellac about once every two years. Yours may be used more often than mine and be exposed to the sun more. Have you asked Jerry or Rollin?
Mark Z
Mark, I'm pretty sure I used what Jerry recommended, Bulls Eye Amber, I don't see where it says that it is waxed on the can. Jerry told me that it is the same stuff that they used to call orange. Do you use something different? I think I put on about 4 coats, I almost used the whole quart. I did let it dry a day between coats, except the last coat I waited a couple hours. Then the boat was stored indoors for a few months. It went on real smooth, not runs or other issues. I didn't talk to Jerry about the planks showing, I just noticed it yesterday, but I did get the scoop from him before I applied it.

I'll post a picture of the can, please let me know if you use something different.
 
Al, I think that is what they used to call Orange shellac and I think it is the waxed variety. For several years now I have been mixing my own shellac from flakes purchased from shellac.net as I could mix it up in any amount I needed and it would be fresh. Once shellac is mixed with denatured ethanol the clock starts ticking and it starts deteriorating. Just how fast I don't know but I want it to be as fresh as possible since old shellac is not supposed to work well. Since I only re-shellac every two years whatever I have left over will be old by the time I shellac again which is why I make it from flakes instead of buying it pre-mixed in the can. The cans used to have a date on them but I don't think they do anymore so one does not know just how old the can is. I am sure Jerry and Rollin go through cans of Bullseye shellac so it never has a chance to get old. Fresh flakes dissolve quickly in ethanol solvent. I can also control the "cut'. I make it a 2 or 3 lb. cut. I put on several coats with an 8 to 24 hour drying period between coats. Lately, I have been rolling it on instead of brushing to get a more even, less mottled look until it looks brown enough, 4 to 6 coats. I used the orange, waxed flakes because that is what Rollin and Jerry recommended. Also, I make sure the denatured ethanol is almost 100% ethanol, not 60 or 70% as is some hardware brands of "ethanol".

It sounds like you used the right stuff and did it correctly so I do not know why it turned white and chalky. When I had a problem I emailed the folks at shellac.net and asked them. You might try asking them about the white, chalky look. I was adding coat after coat since it seemed to dry by the time I got from one end of the canoe to the other. I was told to go to a 2 lb cut and wait 8 hours at least between coats so each coat would be really dry. That helped a lot and solved my bubble problem. I also shellac in the fall so the shellac can "harden" over the winter so I don't get rope marks from tying onto a car.

I would be very interested if you find out why it went white and chalky. I really have nothing to suggest except to re-shellac more often, ie., when it starts to look "thin". Good luck. If I can help further, let me know.

Mark Z.
 
Thanks Mark, I just spoke with customer service at Rustoleum and got the date of manufacture of the shellac I used. It was made on August 13 2021 and I applied it in Nov. or Dec. 2021. They said it has a three year shelf life. When I told them about putting it on a boat and it getting chalky, they were surprised to hear that I would use it for that as it is recommended for interior use.

I will probably mix my own next time, but will probably talk to Jerry first to see if he has any insight. Thanks for the offer for help, if I have any questions about purchasing or mixing I will take you up on it.
 
One possible explanation could have been high humidity level when I applied it. The can says it shouldn't be more than 80%. My basement gets pretty damp. In summer I run a dehumidifier but in cooler months I rely on the heat being on to keep things dry. I don't remember the weather at the time but if it was warm and humid and the heat wasn't running it could jump up quick.

At this point I think I will use the same stuff and apply the same way but manage the humidity. For about 25 bucks and not much work I think it's worth the risk. I really like the shellac for its' ease of application and it looked great when it first went on. Even though the results weren't what I had expected I still feel shellac is the way to go for me.
 
I took a closer look at the hull earlier today and expected the chalkiness to be more on the south facing side that gets the most sun when the boat is on the rack. What I did find was that the chalky pattern matched the waterline, right down to showing the bow light trim I prefer. This adds to my suspicion that high humidity may have been the problem, but I'm no chemist.
 
This adds to my suspicion that high humidity may have been the problem, but I'm no chemist.

This article says trapped water causes milky blushing in shellac and lacquer finishes, and explains some steps to solve(nt) the problem:


If the milky blushing follows the waterline, perhaps it makes sense to make REALLY sure the wood-canvas hull is completely dried-out in addition to doing the shellac application in low humidity conditions.
 
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