Confused about laminating wood - Odd or even number of layer

[Tetsuaiga]

Just a quick question.

I've read before that when you laminate wood together it should be in odd numbers of layers.

With regard to using wood that isn't quartersawn wouldn't you be better using even numbers of layers, so as that you don't have more wood with a convex grain than concave or the opposite. Thereby you hopefully counteract the future cupping by having equal opposing warping.

I can see plywood is a different issue but i'm not interested in that.

 

[custard]

I wouldn't worry about it, use however many lamina are needed to achieve the finished workpiece thickness. By the way, you should be clear on a hierarchy of laminating problems. Things like spring back, applying sufficient clamping pressure, and ugly glue lines are all real issues to be actively considered, cupping is a theoretical possibility but for practical purposes comes way down the worry list.

Good luck!

 

[Tetsuaiga]

Thanks. It's just the odd number thing doesn't make sense to me, unless i remember wrong.

 

[Sgian Dubh]

Thanks. It's just the odd number thing doesn't make sense to me, unless i remember wrong.

The odd number guidance is a significant issue if your plan is to cross laminate, as if you were making something rather akin to plywood. It's not normally of great significance if the long grain direction of all the pieces are parallel, and each piece making up the lamination is equal in thickness. However, if you wish to make up something, say, 24 mm thick out of a piece 16 mm and another 8 mm thick, this might - but not necessarily - be less stable (unbalanced) than a lamination made of a 14 mm piece sandwiched between two 5 mm thick pieces. Slainte.

 

[Tetsuaiga]

That makes sense, I think I'm sure enough in my own understanding to not worry about this anymore.

Thank you Slainte.