Puzzle Box Wood Movement

[DavidRa]

I found some plans for a 5 movement puzzle box with the components made of 9mm hardwood , probably Walnut in my case. I will season the wood indoors for a couple of weeks then thickness to 9mm. The locking mechanism is 3mm .
My concern is that once made the wood, as it is so thin, will move/cup/bow and as it works by components sliding against each other in grooves/ dado’s it will cease to work as intended.

I could make it from 12mm but then the proportions may not look right.
Anyone made anything similar and/or thoughts on will it work long term?


thanks

 

[profchris]

I'd say the important thing is to select vertical grain boards (end on view like this: |||||||||||||||||||||||||||||).

These shrink/expand least across the grain, and shouldn't cup. Flat sawn boards are likely to give you problems.

This is the preferred cut for musical instruments, and I have boards thicknessed to under 2mm which stay flat. They still expand/contract in width by around 2-5% as humidity changes, depending on species, but you can allow for that when designing. I believe Walnut is pretty stable, but I haven't worked with it much.

 

[DavidRa]

Thanks , that’s useful info. I have tried my local wood supplier and he says that quarter sawn is not available and when it is it is expensive. Out of interest can you recommend a source?