# arnishmg is a simple craft. Anyone can learn to do it ^^ / well. The objective is no more complicated than transferring a liquid varnish from a can to the wood.
Natural-bristle brushes are made from animal hair. They are the best brushes for use with all stains and finishes except those that contain water. Water softens natural bristles just as it softens human hair, causing the bristles to lose their stiffness and their shape. The best commonly available natural-bristle brushes are made from Chinese hog hairs. These hairs are thick enough to provide good stiffness, but can hold a lot of
More often than not, a brush is used to apply varnish. Brushing takes a little practice, but the techniques are relatively easy to learn.
There are three basic types of brushes (Photo 1). Each can be used to transfer stain or finish from the can to the wood. Brushes are often taken for granted and that should not be the case. Cheap, disposable brushes are great for applying stains, but it pays to spend some money on a high quality brush for applying varnish, shellac or lacquer.
High quality brushes are efficient tools for applying a finish. They are designed to hold a load of finish and distribute it evenly on the project surface. Quality bristle brushes require time and solvents to clean after use.
finish bccausc thcii ends are split or "flagged" (Photo 2). Finishing with a flagged brush is faster than with a non-flagged brush since the bristles can earn more finish. Also, because there are more bristles in contact with the surface, a flagged brush leaves a smoother coat. Though China bristle brushes are a little more expensive, the improved results are well worth it.
Superior even to China bristle in producing a level surface is an ox hair brush, or a badger brush. Ox hair brushes usually combine ox hair and China bristle. Badger brushes usually combine badger and skunk bristle. They are two to three times as expensive as good China bristle brushes, l he bristles on these high end brushes are so numerous and line, they often don't require flagging. If you clean them well after each use, they will last a long time, so the additional cost per use will be minimal.
Synthetic-bristle brushes are made from polyester and nylon. These brushes became popular for use with water-based products because natural bristles become soft and swollen in water. Synthetic bristle brushes are the best choice for all water-based products. Again, buy a high quality synthetic brush for applying lilm finishes.
Sponge Brushes and Paint Pads
Sponge brushes are cheap and are usually considered throw-away items. They are best used for making finish samples or applying stain.
Paint pads are llat sponge material to which many tiny fibers are attached. Paint pads are best at applying waterbased poly on a large flat surface such as a table top.
Varnish requires only minimal wood preparation. Start by sanding the wood smooth. Sand most woods to 180-grit. Finer grit sandpaper will yield better results on very hard woods, such as ebony and rock maple, which show sanding scratches more easily. When you are finished sanding, use compressed air to blow oil the sawdust. As an alternative, you can wipe down the wood with a tack rag. Tack rags ran be purchased at any hardware store or home center.
Remove any hardware and disassemble the furniture before finishing. To prevent runs and sags, it is best to coat surfaces horizontally. When surfaces must be coated vertically, turn them upside down.
3 A nail board suspends a piece for brushing and drying when both sides get varnished. Put the less visible side on the nails.The tiny imprints left by the nails are almost invisible.
IOf the common types of brushes, the most popular and versatile are those with bristles, whether the bristles are natural or synthetic. Sponge brushes are popular because they are cheap. Most people throw them away after each use. Pad applicators are limited to use on flat surfaces.They are excellent for floors.
Flagged or split bristles allow the brush to hold more finish and lay down a smoother coat. To check your brush, separate out a single bristle. If the brush is China bristle or a good-quality synthetic bristle, the end should be split into two or more strands.
I hat way, any missed runs or sags will be less visible il ihe light source comes from above, which it usually does. If you need to coat both sides of a piece, such as a cabinet door, have a nail board ready so you can flip the piece wet (Photo 3).
It is better by far to apply varnish in a clean room. If that is difficult to achieve, apply it at the end of die day when you can keep movement and thus dust to a minimum. Some woodworkers create a temporary dust-free finish room in their shop by draping pol\-ethylene film on a frame (Photo 4). But remember, while you don't want dust blowing around, you do need good ventilation, so allow for a healthy amount of clean air flow.
Temperature is not critical as varnish will cure in a room as cold as 50-degrees. However, colder temperatures or high humidity will slow the curing process significantly. And that means more time for dust to settle on the surface. Whenever possible, choose a warm, dry area to work in.
When you are ready to start applying the varnish, prime the bristles of your brush by soaking them all the way up to the ferrule in mineral spirits (Photo 5). Squeeze out the excess mineral spirits, but don't shake or spin the solvent out. The bristles should be wet and the brush should be loaded with solvent. This will help the varnish flow better and make clean up easier when you are done.
Use a clean container to mix and apply finish from and another for cleaning brushes. Protect vour skin by usinj^ a pair of thin vinyl gloves.
Stir the varnish gently until any sheen-flattening agents are thoroughly dispersed. Shaking isn't necessary or recommended (Photo 6). Then pour sonic varnish into a clean wide-mouth can or jar I.eave several inches of wall above the level of the varnish. You will need this area to properly load the brush.
The viscosity ol varnishes varies considerably, but virtually all are too thick as they come from the can. You will usually want to cut them with 10-15% naphtha or mineral spirits (Photo 7). Thin is better than thick. Several thin coats will lay down smoother and dry faster than a few thick ones.
Stir the solvent into the varnish gently. Try it on a scrap to see if it flows out well. Then make necessary adjustments by adding either more varnish or more solvent. The finish should flow smoothly off the end of the brush with very little drag.
6Gently stir the varnish to disperse flattening agents evenly throughout. Shaking the can is not necessary or recommended.
4Can't seem to beat the dust devil?
Erect a temporary dust free zone with painter's drop clothes to really protect your freshly varnished piece from renegade dust particles. Don't forget a fan for ventilation.
t Soak natural ^bristles in mineral spirits for a few minutes before varnishing. This charges the fibers with solvent so they more readily release the varnish from the brush.
Apply The Varnish
The application technique is the same no mattei how main coats you are applying. Dip the brush into the varnish so that only the lower third of the bristles contain finish (Photo 8). Gently squeeze out enough excess varnish to prevent ch ips as you move the brush to the wood (Photo 9). Hold the brush near or by the ferrule and touch the bristles to the wood at about 15 degrees (Photo 10).
The surface of the bristles should be shiny, with varnish Mowing gentlv oil the brush. \s you continue to move the brush along the wood, the top bristles will start to dry. Increase downward pressure to keep the varnish flowing out of the brush (Photo 11). A good long-bristle brush will allow you to coat a two-foot strip before reloading. When you come to the end of .i stroke, lilt the brush oft' the wood while still moving forward (Photo 12).
With flat surfaces, start from one end and coat in only one direction with the grain. On raised panel doors, do the recesses first with a sash brush, and then switch to a two-inc h brush for the panel and finally, the frame. On oddly shaped pieces (spindles, legs, mils) go whichever wax is most convenient, but work with ;i drier brush to prevent drips. Be careful not to oxerlap near sharp edges and corners where runs are most likelx to occur.
When you've covered a manageable area and the varnish is still very wet, unload your brush by slowly scraping on the edge of the container. Then "tip-oft" the fresh varnish with the brush at 90 degrees to the wood (Photo 13). If you're working a small area, like the top ol .in end table, you'll be able to tip off the entire surface at once. II you're doing a conference table, tip off the first few passes, then go back and coat the adjacent section.
Dealing with drips and runs is inevitable. It's always best to pick up a drip while the xarnish is still wet. Unload your brush by slowly scraping it along the edge of the container to avoid bubbles. Cio back over the drip or run with your brush, letting the tip of the bristles smooth it out as you pick up the excess. II you find a drip only after the finish has started to cure, level it bx slicing off the bulb of the drip with a razor blade. Slic e it at a loxv angle. Wait until the freshly exposed area fully cures, then sand lightly before applying the next coat.
Drying times van' from brand to brand, but all varnishes cure rather slowly. So to stay on the safe side, applx only one coat per day. Building the finish too fast can leave the inside coats partially cured, which can result in a soft finish.
Varnish's molecular structure changes as it cures.
7To enhance leveling and minimize brush marks, thin varnish 10-15% before use with mineral spirits or naphtha. This works best when you can varnish on a horizontal surface where drips or sags are not a factor.
8 Load the brush with varnish by dipping the first 1/3 of the bristles in the varnish.
9 Lightly squeeze out the excess varnish from brush on side of the container. There's no need to scrape the brush on the side as this removes too much varnish.
1 A Apply the JL \J varnish with the brush held at a 45-degree angle to the wood. Press down enough to deflect the tip so that the ends of the bristles start to splay out on the wood. Drag the brush slowly, about two inches per second, with the grain.
Its solvents can no longer dissolve the cured coating. Each coat must adhere mechanically to the previous one. To help this adhesion, each coat should he lightly sanded before recoaung. Use 220-grit stcaratcd paper between coats and move to a finer grit before the last coat. In areas that are difficult to sand, try 0000 steel wool or a synthetic abrasive pad.
Apply at least three coats of varnish. This builds enough of a finish to look good and wear well. For a deeper look or a gloss finish, add more coats as needed. If you want a very thick satin finish. stick with gloss until the last one or two coats, or rub down the gloss to produce a satin sheen.
It's almost impossible to keep a varnish finish dust free, so you should plan to rub the finish out to smooth it (see "Super Smooth Poly-Finish, p.66).
nAs the varnish drains from the brush, keep the brush angle the same, but increase downward pressure to deflect the bristles and squeeze more varnish out of the brush and onto the surface.
II you use a good-quality brush, vou will want to clean it and wrap it up after each use. This will keep your brush working at its best for a long time. It is wise, in fact, to clean it before you use it the first time in order to remove any loose bristles or dirt.
Woodworkers often don't clean their brushes well because they consider the job a nuisance at best. You will find that you get better results if you make brush cleaning an important part of die finishing process. It's much the same as the time you spend getting a chisel or hand plane tuned and sharp.
1 OLift JL A the brush off at the end of the wood. This keeps the varnish from getting pushed over the edge and leaving heavy drips.
Tip off the fresh varnish with an unloaded brush held perpendicular to the surface. Run just the bristle tips lightly through the wet varnish with the grain. Tipping-off helps eliminate brush strokes.
Here's the best way to clean a brush after using oil based finishes:
STEP 1 Clean by rinsing the brush several times in paint thinner. Squeeze the bristles against the bottom of a container (jar or coffee can) that contains an inch or two of paint thinner. Wring out the bristles with your fingers, (»loves keep voui skin from diving out or having an allergic reaction.
STEP 2 Change the paint thinner frequently, as it becomes saturated with .stain or finish. Keep two or three old containers for brush cleaning. Label them "First Rinse," "Second Rinse/etc. Cycle your brushes through from one can to the next. As the thinner in each can gets dirty, pour it into the previous rinse. When the thinner in the first can is too dirty to use. let it sit for a while. F.ventually the solids will settle to the bottom and you can pour off die clean thinner to reuse.
STEP 3 The final step before washing with soap and water is to rinse the brush in lacquer thinner. Lacquer thinner removes the oiliness left by the paint thinner. The oiliness makes it hard to get the soap and water to suds up and do its job in the next step.
STEP 4 Wash the brush in soap and warm water. You can use any mild soap. A convenient one is dish soap. The idea is to wash the brush until it is clean enough to make suds.
STEP 5 Store the clean brush in the cardboard holder it came in or wrap it in heavy brown paper such as grocery bag paper. The purpose of wrapping is to make sure the bristles dry straight.
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