Stain: Colour Goes In Unevenly Unless You Make It Behave

A DYE dissolves completely and colours the fibres themselves. The colour is transparent, the figure of the wood shows through beautifully, and it fades in sunlight faster. A PIGMENT is solid particles suspended in a binder. They cannot enter the fibres, so they lodge in the pores and in any scratch — which is why pigment stain makes open-grained timber like oak look dramatic, and why it drags cross-grain sanding scratches out into dark lines. Many commercial stains are both. The practical consequence: pigment settles, so a tin that has not been stirred properly gives a different colour from the top than from the bottom. Stir thoroughly, and stir again during the job.

On pine, cherry, birch and maple, stain goes on in patches — dark where the wood is soft and porous, light where it is dense. That is BLOTCHING, and it is a property of the timber rather than a mistake in application. The fix is to partly seal the surface first so everywhere absorbs about the same amount. A thin coat of dewaxed shellac (a 1-pound cut) is the most controllable conditioner, and a commercial pre-stain conditioner does the same job. Sealing reduces how much colour is taken overall, so the result is lighter. That is the trade, and it is why the sample board matters: you are choosing between even-and-lighter and blotchy-and-darker, and you want to see both before deciding.

Apply generously, leave it the stated time, then wipe the surface dry. Depth of colour is controlled by how long you leave it before wiping, not by how much you leave on. Stain left lying on the surface never dries properly and stops the finish above it from bonding. That is the classic failure: a surface that stays tacky for weeks, or a varnish that peels off in a sheet months later carrying the colour with it. Work in manageable areas and keep a wet edge. A stain that dries where two applications overlap leaves a dark lap mark, and on a large tabletop that is the most likely way to spoil it.

There is a safer way to get colour: add it to a coat of finish rather than putting it into the wood. A TONER — dye mixed into shellac or varnish — sits between coats where it can be adjusted, and if it is wrong it comes off with the coat. That converts an irreversible decision into a reversible one, which is why it is standard practice in furniture work. It also lets you sneak up on a colour across several thin coats rather than committing in one. Seal the bare wood first, then tone, then finish over the top. Keep a note of the recipe — proportions, number of coats — because an unrecorded toner is impossible to reproduce when you come to make the matching piece.