Since each hair naturally tapers to a fine tip, single strays facing the wrong way are picked out with tweezers and discarded. It's a process known as de-blunting and one which requires the eyesight of a desert hawk.

The hair is then cut to length according to the brush size, and just the right amount is fed into a metal ferrule. Too much and the hairs will splay. Too little and they won't fit snugly.

The brushmaker feeds the hair into a small brass cylinder, taps it to bring each strand into line, then lifts and twists it out of the cannon with a diaphragm. This action pulls the outside hairs down, producing the candle-shaped knot. Brush heads to a size 9 are secured with a dab of glue. Larger sizes are hand-tied with cotton thread.

The knot of hair is then fed into its ferrule, measured precisely for length, and glued in place with a touch of epoxy resin.

The ferrule is heated briefly over a Bunsen burner before the birch wood handle is slipped into place. As the metal cools, it grips tight.

To make absolutely sure it's securely in place, the brush is fed by hand into a small vice, the only machine in the room. This hand-operated device crimps the metal and creates the distinctive decorative border at the top of the ferrule, called the knurl.

The handle is printed with the appropriate model name and size, using a small printing press - the only other machine in the workshop.

In its final stages, each brush head is worked with a metal rod against a leather strap to tease out any loose hairs, and checked again for blunts. Finally the brush is dipped in a weak solution of gum arabic and brought to a fine point.

Nothing beats a superior quality sable for pointing ability, and thanks to the microscopic filaments along each hair, it holds a wash better than any other brush.

But in the search for a more economical alternative, Daler-Rowney's experimental work with polyester fibres produced the pioneering Dalon series. In performance and handling the Dalon is considered by watercolour artists to be the first serious rival to the sable.

To meet the particular demands of working in acrylics, Daler-Rowney developed the Cryla range. A unique blend of six different synthetic fibres combine to create a brush with the durability and resilience required by both fine art painters and decorative craft artists.