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I'm making a picture frame... (3 8x10 side by side with simulated barn doors on either side. I'm using rough cut cypress wood that came from the sawmill and has a moisture content of 60%. I've planed a little of the rough cut off one side and planed the other side (back) smooth to a thickness of 7/8" I also live in Central Fl so the humidity is high in my wood shop where I'm putting the project together. All the joints are butt joints that have been glued and held together with a screw. I have the frame 90% complete and I'm now wondering if I should wait for the moisture content to come down before I start putting my finish coats of shellac or can I reasonably expect the finish to dry okay despite the high moisture content. I don't think even if I bring it inside for a couple of weeks that I'm going to see much improvement in the moisture content. Any input will be greatly appreciated.

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    Hi, welcome to StackExchange. Sorry for how this sounds but why would you even want to work with the wood this wet? You can't reliably glue wood with a high MC (way below 60%) with I think any common glue, although foaming poly may be more tolerant of it than most. And screw hold is going to be iffy. So I think the shellac is the least of your worries to be frank. But that said shellac is pretty famous for how well it sticks to just about anything, although I'd expect issues with clouding. Also realise that if it does work the shellac is going to significantly slow drying.
    – Graphus
    May 11, 2023 at 6:15
  • I agree with Graphus and don't understand why you would even begin to try and use wood that wet. Even in FL it will dry out a lot more than that if you keep it out of the rain. That is just asking for lots of problems.
    – bowlturner
    May 11, 2023 at 13:48
  • I sincerely don't mean to pile on, but how did you measure 60% emc? That's out of range of a handful of moisture meters that I glanced at. May 11, 2023 at 15:04
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    Kind of expected the comments I've gotten. In my haste to build this project out of wood that had that rustic barn wood feel is the reason I chose the rough cut cypress. Had no idea it was that wet, so I acquired a moisture meter to check and that's when I found out how bad it really was. I plan to bring it into the house and see if it dries out some without pulling itself apart. If it does I'll chalk it up to experience and learn from it and start over with different species of wood.. Making this for a co-worker and don't really want to be giving her something that is not going to last.
    – billa32778
    May 12, 2023 at 12:31
  • Well the wood will certainly air-dry from this point onwards. Be interesting to see how it fares as it does! The (very) rough rule of thumb for drying once wood in planked is a year per inch of thickness. So with a margin for error this would be worth revisiting May of next year; assuming it does dry acceptably flat and straight I'd expect having to take it all apart and putting it all back together again (probably using longer screws, if the design allows).
    – Graphus
    May 13, 2023 at 7:21

1 Answer 1

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Putting aside the concerns about working with wood this wet, I think there's a reasonable chance the shellac will bond to the wood OK.

For starters, shellac can bond to oily wood1, which is presumably much more challenging.

And the surface of the wood won't be as wet as the moisture meter measured, it never is. The surface of wood is always more dry than the interior wood on boards of any reasonable thickness2.

Regardless of the bond question, I'd expect issues with clouding however. Especially if attempting to build up a decent coating of shellac. Shellac is infamous for clouding, where literal cloud-like white staining can show up in the film, particularly when working in cold conditions, e.g. due to moisture condensing from the air onto the cooling surface. Here your shellac doesn't need to do that neat trick for water to show up!

An additional concern is that fully shellacking now will only slow drying and this wood has a lot of water to lose, which can already be expected to take a long time.

So my recommendation would be to just apply one coat, or two thinner coats now and if the project has held up OK as it dries to complete the finishing process, in a year to 18 months.


1 For maximum enhancement of figure or depth (AKA "grain pop") wood may be oiled just prior to the application of the first coats of shellac.

2 Hence one of the inherent problems with pin-type moisture meters, measuring at the surface or too close to it and possibly not compensating correctly for these drier readings.

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