On July 8, 2018 at 21:06, Ernie Gilman said...
I see here something that hints at how you and I disagree on some things: it's the point of view.
I say that a cabinetmaker calls the direction of the grain in a piece of wood its "length" while the same direction in particle board, which has no grain, is its "width."
You say "Doesn't need to be considered as having 'grain' since...."
The starting point here was that the cabinetmaker IS TALKING ABOUT WOOD WITH GRAIN. The ideas flow from that starting point. Grain is an obvious and necessary property of the material under discussion. Thus "grain" has to be taken into account if it matters. It matters to the cabinetmaker.
Frankly, then, I don't know what you're talking about.
The shelves are plywood, so my point about no direction stands. Those dimensions, which are close to square, would be 'width' and 'depth'. If the shelf is long and shallow, they would be referred to as 'length and depth', but some support wold be needed for a long shelf because it will sag if a heavy object is placed in the center.
Width and length refer to the shorter and longer dimensions, respectively, regardless of material but not to the place where it fits. If a cabinet has an opening 36" wide, the board will need to be about 36" long in order for the grain to do its job of supporting the load, which fits your use of 'length'. An amorphous material like MDF, Particle Board, OSB or solid surface is agnostic WRT which way it's oriented unless it proves to be somewhat less forgiving in one of them. You could have a scrap that's at 45 degrees to the original panel's dimensions and it will work as well as if you had cut it by using the edges as a guide. Some stone materials are less forgiving, so it needs to be reinforced in some way. The grain of some wood species make them better for wide shelves and tops without multiple points of support from below because the inter-cellular bond is stronger and the way it's sawed is less important- if you try using quarter-sawn pine boards to make a deep shelf, it will need some support in the middle of the span- simple shelf pins won't support a heavy object that's placed in the middle because the board will crack across the thickness but if you use flat-sawn (also called 'plain-cut', 'plain sawn', etc'), it will be fine.
BTW- I posted about the delay in delivery of the cabinet quite a while ago- the guy still hasn't been back to install the drawers and doors. I don't know where they found this payaso, but if I hear that they paid a lot for this POS, I'm going ballistic, especially if he says that he was waiting for some specific material. Maybe he was waiting for his trained beaver's teeth to grow back after hitting a nail.
