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I have found various guides and plans for building a box or chest with a curved (coopered) lid that involve gluing the sides of the lid to the slats forming the top, which are themselves glued together. Here are some examples: one, two

Does this method allow for enough seasonal movement to prevent the lid from coming apart, deforming, or otherwise getting messed up? If not, is there a better way to build this type of lid that does?

I imagine that one possibility is to keep the slats separate and leave gaps between them, but I prefer to avoid this since I want a smooth continuous surface on the lid.

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  • There's no inherent allowance for movement in the basic design of these with the joint with the end caps being a classic cross-grain situation (which is generally something to avoid with any sort of rigid fixing, very much including glueing them in place) so it is entirely possible for movement to cause an issue especially if there may be extremes of temperature and humidity where the box will be housed. What wood were you thinking of building yours from? Hopefully not pine!
    – Graphus
    Commented Dec 6, 2018 at 8:23

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As Graphus stated in comment, the wood members in the arched top will expand and contract while cross grain ends will not. The differences in expansion can easily cause failure in the top. I can think of two ways to reduce this problem.

The first is to fabricate the end panels using the same wood with the grain oriented vertically so that the top and the ends are expanding at nearly the same rates. I say 'nearly' because there could be some difference in expansion/contraction due to the curve of the top vs the side panels. For a small box this should be relatively small and could be successful. The larger the box, the more pronounced the difference mighty be.

The second option would be to secure the individual wood slats only to the end panels and join each slat to the others using and tongue and groove connection similar to the approach used for wood flooring. That way the individual movement in each slat is absorbed in the joint between them. This approach has the advantage of absorbing a much larger wood movement making larger boxes much more stable.

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    +1, I think the way these were typically done originally was the slats were nailed on individually and no glue was used. Nailed construction allows for some movement, although slim gaps might open up between individual slats (air-dried wood exclusively in this period, so I don't know if it would ever dry out enough under normal circumstances for this to occur). Plus, as we're all aware from pirate movies, chests could have had iron bands applied too which could help maintain the dimensions by force. But obviously neither of these are particularly popular in these days LOL
    – Graphus
    Commented Dec 8, 2018 at 7:57
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    @Graphus Of course the iron band were also used to ring the barrels containing the pirate's rum! The barrels are not so popular these days although the rum remains so.
    – Ashlar ♦
    Commented Dec 8, 2018 at 21:31

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