Micro brushes are disposable sticks with a small fibre head on the end. They pick up a very small quantity of liquid and release it exactly where you aim, which makes them the tool of choice for spot-applying glue, accelerator, wash or decal setting solution, for lifting excess out of a panel line, and for cleaning a crevice an ordinary brush will never enter. Several head grades are offered, from the finest to a stiffer, more absorbent version. Keeping two or three grades on the bench costs very little and removes most of the reasons to risk a good sable brush.
You are handling liquids that would ruin a good brush: cyanoacrylate, accelerator, aggressive thinner, debonder. A micro brush is thrown away afterwards and nothing needs cleaning — and because it is new, it has the same shape and absorbency every time. The second advantage is size: the finest head measures under a millimetre, so it reaches into a seam, around a canopy frame and between interior details.
For a micro drop of glue, for placing a wash exactly in a groove, and for spots where a larger head would lift paint from the surrounding area. They come into their own in small scales, where every tenth of a millimetre counts.
The general-purpose grade for most work — applying decal setting solutions, blending a small effect, wiping excess back. If you are only going to keep one grade, keep this one.
These hold more liquid and carry it further. They are used for cleaning larger areas, for applying thinner when stripping paint and for working with pastes, where a fine fibre would not cope.
Never dip the whole head — the tip is enough, otherwise the liquid runs back down the stick and drips where it should not. Let the head draw the liquid up and wipe the excess on the rim of the pot. When wiping, draw the stick in one direction and change it the moment the head is dirty: a loaded brush puts colour straight back onto the surface. For work in one spot it helps to use two heads, one to apply and one dry to lift the excess immediately.
For actually painting a shade, reach for a proper tool from brushes — a micro brush is an applicator, not painting kit.
