Upended

For those of you who’ve been following along for a while, you might remember these boxes.

http://secondwindworkshop.blogspot.com/2011/06/form-over-function.html 

The handles on these two lids marked my first foray into bent lamination.  While I was very pleased with how the bent laminated handles came out, the lids themselves have given me a little, unpleasant surprise.  I’ve had them on display here in my office for the past several months and it looks like the humidity difference between the Twin Cities and Denver has put a little cup in the lids.

This first lid has cupped just a little, but it is noticeable.

The cup on the second lid is a bit more drastic.

 

The movement is pretty significant, given that these lids were originally dead flat and had a nice, snug slip fit onto the boxes.

I’m pretty disappointed because I specifically used quarter sawn Wenge to avoid any movement of the wood.  The lids were made by laminating two pieces of the quarter sawn Wenge with the grain directions rotated at 90 degrees to each other.  My hope was that this would have formed a very stable lid with no chance for movement or expansion/contraction.

So, my fellow woodworkers, what do you think may have gone wrong?  Was I wrong to assume the stability of the quarter sawn Wenge, or the offset laminations?  I hadn’t done a lot of work with Wenge, so did I underestimate the impact of the humidity differences between summertime in St. Paul and Denver in January?   What would you have done differently with lids like these? 

I’ll be interested to see how they look once summer rolls around again.   It’s only been over the last couple months that I noticed the movement, so here’s hoping they come back into shape again.

Pete