Popular Woodworking 2008-11 № 172, страница 57

Flexner on Finishing

BY BOB FLEXNER

Applying Wiping Varnish

Practice makes perfect.

I've written several times in these pages about wiping varnish beingone of the best finishes for a woodworker not usinga spray gun - most recently in November 2005 (you can find thai article in the finishing section ai popular woodworking.com). Wipingvarnish issimply alkyd or polyurethane varnish thinned about half with mineral spirits (paint thinner). The thinning makes the varnish easy to wipe on the wood.

Ifyou remember. 1 pointed out that the big problem with wipingvarnish is manufacturers concealing what's in the can. Instead of calling the product what it is-thinned varnish-they commonly use uninformative names such as "lungoil," Seal-a-Cell. Waterlox, Profin or Salad Bowl Finish.

This user-unfriendly marketing practice has prevented the finish from being treated asa "category" in the manner of other finishes such as oil, shellac, lacquer and water-based finish.

The advantage of grouping all thinned varnishes as a category is that it allows us to discuss uniform application procedures that apply to every brand. For this article, we're goi ng to avoid con fusion by making our own wipingvarnish.

I've designed this article asastep-by-step instruction using scrap wood, similar, for example, to an exercise in learning to cut dovetails. Ifyou would like to follow along, you will need the followingsupplies, most of which are available at a home center.

■ A quart of gloss, oil-based polyurethane varnish (approximately $8).

■ A quart of mineral spirits, also known as paint thinner (approximately $5).

■ A clean, wide-mouth jar with a lid (.from your kitchen).

■ Latex or other type of protective gloves (approximately $2 for 10 pair).

A simple solution. Above is everything you need to make and apply wiping varnish, which is simply alkyd or polyurethane varnish thinned about in half with mineral spirits. By first practicing on scrap, you'll feel more comfortable when you tackle the real project.

m I .int-free ragssuch as old,clean T-shirts, cheesecloth or Scott Rags, which arc paper rags in a box or on a roll (approximately $2 for the roll).

■ Asheetof#400-grit sandpaper (approximately $4 for a packet of three).

■ A 2' x 2' or larger, sheet of V2" or -V4" veneered plywood or MDF. Any hardwood veneer is OK (from your scraps, a wood sup

plier or one of many cabinet shops that often t h row away pieces this size).

■ A brown paper bag (from the supermarket).

The procedure is detailed in the following pictures.

Bob is author of "Understanding Wcxxl f inishing "and a contributing editor lo Popular Woodworking.

90 ■ Popular Woodworking November 2008

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