Wood thickness for loom

[Tom Dunn]

I need to build a triangle loom for a friend.

I want something pretty nice, so I'm thinking ash, cherry, or whatever hardwood I can get easily, locally.
8' on the hypotenuse, half-lap joints on the corners, two different colored nails alternating.

If I'm looking for stock about 3 inches wide, in the interest of having the triangle remain flat over time, would you go with 3/4 stock or with 5/4?

 

[Mike Davis]

A little bit depends on the tension involved, but in the tradition of over engineering go at least 5/4.