Woodworker's Journal 1993-17-2, страница 27

edges of the pads enable you to get into tight comers, such as when finishing the inside of a drawer or cabinet. The next best tool for applying water-based finishes is a good quality synthetic bristle brush (polyester, nylon, or a blend of the two) with soft, well-flagged bristles.

How To Spot Quality

Whether you go with a natural or synthetic bristle brush, it pays to buy the best you can afford—within reason. As I mentioned earlier, most woodworkers won't notice much difference between a SIO brush and $30 brush of the same size. Here are some general quality features to look for:

Fill: This term refers to the amount or number of bristles contained in the brush. Varnish brushes usually have less fill than wall brushes of the same width, although an expensive varnish brush will usually have more fill than a cheaper one. In a good varnish brush, you'll notice that the fill is nearly as thick near the brush tip as it is at the base.

Bristle Mixture: A quality varnish brush also contains a good mixture of bristle lengths to form a smooth, even taper toward the tip of the brush. (On cheaper brushes, the shorter bristles look chopped off in layers, like a cheap haircut). Ideally, the shortest bristles should extend at least 1 in. out from the base, or ferrule. Also. 70-80 percent of the bristles should be full length. They should feel nearly as full near the tip as they do at the base when you wrap your hand around the brush.

Hristle length and thickness: Cheaper brushes usually have shorter bristles than more expensive brushes. When viewed sideways, cheaper brushes are also thinner (because they contain fewer bristles). Use the following guidelines for choosing a flat varnish brush: Brush width and bristle thickness is measured at the ferrule; overall bristle length is measured from end of ferrule to tip of brush.

Splitting hairs: While we don't want to have split ends in our ow n hair, this condition is desirable in a brush because it helps eliminate brush marks: Natural bristle brushes have naturally split or flagged ends, which continue to split as the brush is used. On higher quality synthetic brushes, the bristle ends are flagged during the manufacturing process. On a good varnish brush, about 80 percent of the bristles are flagged, and the flagging extends from 'A in. to '/i in. back from the tip of the brush. You can tell good flagging by rubbing your hand across the working end of the brush—it should feel smooth and soft, not stiff and prickly. While you're at it. fan the brush briskly a few times; if more than one or two bristles fall out, don't buy the brush. Maivh/April 1993

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Handles: As far as I'm concerned, plastic handles are just as durahlc as wood ones, if not more so. But. for some reason (probably esthetics) the more expensive natural-bristle brushes usually have wood handles. If you're buying a consumer brush, go with a plastic handle, rather than a wood one. I've found that the wood handles on chcaper brushes are a varnished or painted softwood: on these, the handle tends to swell when exposed to water (such as when washing the brush), eventually loosening the ferrule. Professional brushes usually have sanded, un-painted hardwood handles. Some finishers prefer long, rounded handles; others prefer shorter beavertail handles. When I shop for a brush. I pick it up and pretend to paint with it to see how it feels in my hand.

Ferrules: Better brushes have durable nickel, brass plated, or stainless steel ferrules; cheaper brushes have thin steel or tin ferrules, w hich arc sometimes painted. On cheaper brushes, the ferrules start to rust after several cleanings.

A Few Tips On Brush Care

Never allow a brush to sit in a can of water or solvent for any lenglh of time—this is the quickest way to turn even the most expensive brush into junk. If you need to walk away from the project for a few hours and don't want to clean the brush, w rap it neatly in aluminum foil to keep the finish from evaporating, or suspend it in a coffee can partially filled with solvent, as shown in the drawing.

After use. w ash the brush thoroughly in solvent and/or warm, soupy water and rinse it out thoroughly. Next, remove excess water w ith a brush spinner or by shaking it gently. Never slap or bang the bristles, or w ring them out with your hands—this will delorm or break the bristles.

When the brush is nearly dry, gently comb out any tangles in the bristles with a brush comb, and wrap the brush in new spaper or the original plastic or cardboard cover that camc with the brush, being careful not to deform the original shape of the bristles. Hang the brush vertically on a nail or hook, bristles down, to store. jTCJ]

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