Grain direction

Grain direction is the one constraint in sheet work that has nothing to do with arithmetic. A layout can be perfect on material and still be wrong, because a door has its figure running across instead of down and everybody who walks into the room will see it.

Which way it runs

On a veneered sheet the face grain runs along the long dimension. On a 2440 by 1220 sheet that means along the 2440. This holds for oak, ash, walnut and every other veneered board you are likely to buy, and it holds for the face veneer of most plywood too.

It is not a law. Cross grained veneered panels exist, some plywood is made with the face across, and if you buy short sheets you should look rather than assume. Look at the sheet in front of you, not the rule in your head.

What has no grain

Melamine faced chipboard has no grain worth respecting unless it is a wood effect print, in which case it has a very obvious one. Plain MDF has none. Acrylic, aluminium composite and solid surface have none. Anything with no grain should be left free to turn, because that is free material and there is no reason to refuse it.

The kitchen carcass job leaves everything free for this reason, and it is part of why it gets down to 13.9 per cent waste.

When it actually matters

It matters on anything a customer looks at directly, and on anything structural. In practice:

• Doors and drawer fronts, always, and they should all run the same way as each other
• Tops, sides and any exposed end panel
• Adjacent parts that are meant to read as one piece of timber
• Structural plywood, where the face veneer direction is a strength decision rather than a looks one, as in the marine ply job

It does not matter on carcass backs, drawer bottoms, hidden shelves, packers, jigs or anything that will be painted and is not structural.

What locking grain costs

Less than people expect, and sometimes nothing at all.

We ran the oak sideboard twice, once with all fourteen parts locked and once with the locks off. Both come back as 3 sheets, with the same waste figure to one decimal place. Respecting the grain on that job cost exactly nothing.

The reason is worth understanding, because it generalises. The parts that would gain most from turning are the long ones, and a 1764 mm shelf turned ninety degrees is 1764 mm tall, which does not fit on a 1220 mm sheet. It was never going to turn. The parts that could turn, doors and dividers, are close enough to square that turning them gains almost nothing.

So on cabinet work with long parts, grain locking is usually free. Where it does cost you is small square parts on a job with a lot of them, which is exactly where the grain usually does not matter anyway.

The real cost of grain

Not board. Remakes.

The sideboard was cut once before with the layout worked out on paper, and two parts came off the saw ninety degrees out: a door and an end. On oak veneer at 700 mm that is the first thing anyone sees. Both had to be recut and the offcuts were the wrong shape, so a fourth sheet was opened.

That is how grain takes money off you. Not a percentage on a layout, a sheet bought on a Friday afternoon to replace a door.

In Cut Solver

Grain is a column on the parts list with three states: along the part's length, across it, or free. Set it per part, not per job, because most jobs are a mix.

Then check the layout honoured it. Grain locked parts are drawn with their direction marked, and the check to make is that every door on the diagram is standing the same way up. That check is in reading a cutting diagram.