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I’m making a pine wood box that will be used outdoors from time to time, not all year round but may be exposed to some rain/moisture. I've used simple butt joints for the corners as it’s getting painted so wasn’t too worried about anything too fancy. I've placed two screws in each joint and by mistake picked up the wrong glue and ended up using Evo stick interior wood glue. Do you guys think it’ll still hold up? It’s to carry a few tools in, I don’t want it breaking apart first use! Cheers!

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  • The climate is also important. Here in Finland you can get about 3 months of 100% RH in a row during the late autumn, early winter and any glue that cannot handle that will fail no matter if you get direct rain or not. Apr 6, 2022 at 14:26
  • Please link to your product's web page. I'm not familiar with Evo, and a search on your description apparently led me astray.
    – isherwood
    Apr 6, 2022 at 16:12

4 Answers 4

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I think it will hold up as long as the screws are holding for sure. The glue will fail if your paint allows moisture through, but should last plenty of time as long as you keep a decent coat of paint on it.

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  • This isn't an answer. Screws and glue perform different jobs, and paint isn't waterproof. If it rains, the wood will be damp.
    – isherwood
    Apr 6, 2022 at 13:29
  • Well, maybe it's an answer, but it's deceptive.
    – isherwood
    Apr 6, 2022 at 13:36
  • Well, he didn't really say what sort of paint he was applying, so I couldn't address that directly, but even if it was latex, that would be better than nothing to protect the glue. The glue kind of becomes irrelevant anyway because of the screws. A decent coat of paint on the entire thing also adds to the strength, but not as much as the screws or glue. So, unless they are using it to carry water like a bucket, I don't see a concern here. Apr 6, 2022 at 17:21
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I largely agree with you and UnhandledExcepSean, but... Make sure you paint the underside and entire inside as well. Even humidity or minor water intrusions can kill the glue's ability and longevity.

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  • Corner protection could be helpful too, either in the form of brass-ish metal plates that screw on, or some extra furring strips of wood that can act as sacrificial runners. White paint on the inside to help with visibility.
    – Criggie
    Apr 6, 2022 at 12:24
  • Agree with what? There's no assertion about the question in the question post. And the answer you reference is poor and speculative. Your answer should stand on its own.
    – isherwood
    Apr 6, 2022 at 13:31
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A note I see none of the other answers mention - while PVA glue is water soluble, it will also re-cure as it once again dries. If the joints are strong and tight, water intrusion is difficult (often in lutherie one must use steam because water just won't creep into the joints well if you've made your joinery perfect), couple that with a coat of paint, and the fact that you are probably strong enough with the screws alone, and I wouldn't be very concerned.

Also of note that if the box is a planter or something, you'll notice moisture creep through the paint from the constant exposure to moisture on the inside, and it will cause the sides to bow outwards, possibly destructively. Dovetails/joinery can help with this, but when wood wants to move, one way or another it will succeed in doing so.

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  • "when wood wants to move, one way or another it will succeed in doing so." +100! However, I'm not so sure that the glue would be where you want it if it softens in the rain. As a liquid, it will tend to flow downhill. I do agree that the screws are likely to be enough to hold it in place.
    – FreeMan
    Apr 6, 2022 at 16:00
  • @FreeMan A tight fitting joint should allow both the relatively high viscosity of wood glue, coupled with any capillary action (both in the wood, and in the joint) to hold it in place. That's an additional bonus for a tight fitting dovetail - you should be able to set/unset it ad infinitum and capillary action will keep the glue in the right spot Apr 6, 2022 at 16:56
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For it to last longer, joints using motrice and tenon or dovetail were invented.

Much better at dealing with odd bits of moisture etc Those joints rely on the strength of the wood, not just a few screw threads.

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    This doesn't answer the question.
    – isherwood
    Apr 6, 2022 at 13:31

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