That's an important aspect! A friend of mine had some shafts hanging on a small rack, that was fixed with its backside to the wall. The wall itself was partly in the level of the cellar, and the opposite side of that wall was the stairway area. He did this for presentation in his billard equipment shop.
All these shafts hanging like this on the wall vertically of course! And all these shafts were warped!! The convex side of warpage was at each shaft the same side: --> the wall side!!
What happened? It was in the end of our winter period, the stairway area was not heated unlike the room that was heated of course. By this reason the temperature of the air between shafts and wall side was a few degrees below the temperature of the room side. There wasn't any air circulation at the shafts' wall side and thus the climate of the wall side was different to the room side. Lower temperature and thereby a little higher relative humidity of the air. This situation caused a little higher humidity of the wood at the wall side than at the room side!!
An unequal inner tension in the shaft's wood caused by an inner gradient of wood humidity forced the shafts in the warped shape!
Knowing such a curiuos circumstance and how sensitive wood can react on humidity changes I also think that temperature and humidity effects are much more important when it goes about appropriate storing methods than anything else.
By the way: From these shafts were 2 of them predator 314/2, 2 predator Z2 and 1 solid wood peachauer, all shafts brandnew. I only want to mention this beeing sure that no laminated shaft construction can prevent such a warpage caused by a wrong storage. Only the level of moisture based warpage may vary under different constructions and wood qualities.
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