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Two summers ago I visited a friend of mine at his cottage, and although the day was fabulous, the expression on his face as I pulled up was anything but sunny. It didn't take long to see why. He'd just spent the last three hours on his hands and knees making precious-little headway sanding his peeling deck back to bare wood in preparation for refinishing. Dozens of gucked-up, 1/4-sheet pieces of 120-grit sandpaper littered the disaster zone, and you could tell by the sweat on his brow and the wild look in his eyes that he wasn't feeling as polite as his conversation would lead you to believe. The fruit of his labour was a tiny 6 sq. ft. patch of bright cedar amid a sea of peeling, ugly, grey decktop. At the rate he was going, he had 6 days of sanding time ahead. The fact that the deck was only 3 years old, and was peeling because it had been finished improperly by a contractor in the first place, was something neither of us had the heart to discuss.
The problem was his sander -- a lightweight palm-model -- great for smoothing-out a furniture finish between coats, but definitely out of place for anything like deck patrol. That little sander was as useful that day as an ashtray on a motorcycle, though he didn't know how he could do better.
Frustrating experiences like these aren't unusual for beginners, and I wonder how many newcomers give up woodworking without ever really getting started, simply because of equipment that's ill-suited to their needs. It's easy to see why. Every machine on the market -- sanders included -- are routinely touted as the ultimate machine for everything, even though each one is actually only suited to a few specialized jobs. No wonder poor purchases happen all the time.
If You Can Only Buy One
Setting up a workshop is all about dealing with compromise. Everyone wants to get the most woodworking fun from the least investment of money and space. In the real world the best you can hope for is choosing the least compromising compromises.
Resigned to this truth, the first sander you should buy for general shop use is a handheld belt sander. You want a medium-size unit with a dust bag (though all brands still kick dust into the air), sporting a belt in the 3 x 21 to 3 x 24 range. This machine won't do everything, but it'll do the important, power-intensive jobs well, and that's all you can expect. I'd steer clear of 4 x 24 machines, unless you've got a good reason for the extra capacity. They're often heavier than their smaller cousins, a drawback that you'll notice about 5 minutes after firing-up for the first time.
A belt sander is THE machine for general-purpose smoothing and leveling of solid wood and veneered sheet goods. It's vital for preparing edge-glued solid panels after they come out of the clamps, and does a reasonable job sanding cabinet face frames. In situations where you need to remove lots of wood quickly, don't be afraid to use your belt sander across the grain. Just be sure to sand out all the ugly scratches before you apply any finish. |
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I keep 80, 120 and 150-grit belts in my shop; anything coarser seems unnecessary, and anything finer I prefer to tackle by hand or with my random orbit sander. A rubber crepe block cleans dust and resin from all sanding belts and multiplies their life many times.
When It's Time to Add Another
As useful as the belt sander is, it'll soon leave you wanting more. The problem is lack of finesse. Belt sanders are powerful, somewhat clumsy machines, and they can remove wood more quickly than you'd like sometimes. They also sand in only one direction, which inevitably leads to cross-grain scratching in applications where two or more pieces of wood meet from different angles, like at the corner of a cabinet door frame, for instance. The ideal compliment to the belt sander is relatively new on the market, and there are lots of great models to choose from.
Random orbit sanders comes in two versions -- the smaller palm-style models, and the larger angle-grinder machines. Both have round discs that move with two actions at once. First, they spin around a central axis, like a regular disc grinder. They also orbit randomly at the same time. The two motions come together to produce a sanding pattern that leaves behind very few cross-grain scratches, regardless of the fact that the abrasive moves along, across and diagonally to the wood grain.
Random orbit sanders have one drawback: they remove material too aggressively for optimum use by a beginner sanding lightly between finishing coats. That's why I recommend a similar-looking, though different, machine as the third sander you should buy. The only finishing application where a random orbit sander makes sense is buffing. By placing the sander's disc on top of a Scotch-Brite pad that's resting on a varnished work piece, you can buff-down a glossy surface, giving it an even, satin sheen.
Sanding Between Coats is Key
It's impossible to properly finish wood without sanding lightly between coats to level and smooth the wood grain. Even if you start out with smooth wood, it won't stay that way after the first coats of urethane, varnish or shellac dry. The wood fibers that had been lying down pop up as they absorb finishing liquid, then harden in the popped-up position. Sanding -- especially between the first and second coats -- is the only way to get the surface smooth again. Sandpaper with a 220 or 240-grit rating is ideal for this job.
Although it's quite possible to complete between-coat sanding by hand, a non-orbital, palm-style finishing sander makes the job faster, especially when you've got to cover a lot of ground on big furniture or wood floors. Considering the other kinds of sanders on the market, there's no need to use a finishing sander for anything else. An in the time before you get one, finish-sanding by hand is quite practical. In fact, sanding by hand around corners and rounded parts is the only way to go. Power sanding in these areas, even with a mild-mannered sander, will instantly chew through the finish and get you back to bare wood. Sometimes there's just no substitute for the human hand.
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