Hand Powered Sanding
Sanders are one of the most frequently and extensively used power tools in workshops. Given how much use they get, it makes sense to choose a sander that suits you ergonomically. If you do a variety of different types of sanding tasks in the shop – large flat panels, narrow edgework, molding and profiles – then you’ll want to consider purchasing task-specific sanders. Unless you work in a production environment and use a sander for hours every day, a power sander will likely last for many years, if not decades.
One of the most common problems with any sander is the presence of swirl marks and milling marks that haven’t been eliminated by thorough sanding. You can reduce both of these surface marks by using high-quality abrasives that have consistently uniform grain patterns, using a progressively finer array of sanding abrasives (typically 100, 120, 150, 180, and 220 grit), not hand-forcing the sander to work harder or more aggressively than it wants to and keeping the work surface clear of dust.
The best way to keep the surface you’re working on free of dust is with a dust extractor. You’ll also be glad not to have all that dust floating around when it comes time to apply a finish. And, of course, in the long run it’s a lot better for your lungs. A dust extractor will also prolong the life of your sanding discs or sheets. If you do a lot of sanding, then consider investing in an anti-static hose (which will only work with an anti-static dust extractor).
If you’re a hobbyist woodworker or DIYer who only does occasional sanding, then a consumer-grade sander is probably the better value-conscious choice. A premium-grade sander will give a finer finish faster, provide better dust extraction, vibrate less, last longer and ultimately provide a better return on investment.
In this article we look at the four most common types of power sanders. In the next article in this series we’ll look at benchtop sanders.
Because of the way their pads move in dual directions, random orbital sanders (right) are more aggressive than sheet sanders (left). They can both produce the same quality surface, but random orbital sanders do it much quicker. (Photo by Carl Duguay)
Random Orbital Sanders (ROS)
These are, by far, the most popular sanders, and for good reason. They’re as effective for aggressively sanding large surfaces as they are for delivering an ultra smooth finish. Unlike other sanders, the backing pad moves in an orbital motion while at the same time moving in an eccentric (off-center) orbit, leaving an irregular scratch pattern of swirl marks that can be quickly removed by hand sanding or scraping before applying a finish. Sanders with a larger stroke (5/16″) cut faster; those with a smaller stroke (5/64″) cut slower. Many models use a compromise stroke of around 3/16″. Increasing sanding speed (and/or downward pressure on the sander) will generally increase cutting power and help to decrease sanding time, but it will likely increase swirl marks. These sanders are available with both 5″ and 6″ backing pads, and have five or more holes in the pad through which dust is extracted. Pads take either PSA-backed or hook-and loop sanding discs that are quick and easy to mount and remove. Most include a dust bag or canister while some have a port for connecting to a dust extractor, which provides superior dust extraction.
From $35 to $850.
Festool ETS EC 125 EQ
A professional grade, general-purpose sander with a medium stroke of 3 mm (just under 1/8″), powered by a long-life 400- watt, 3.3-amp, brushless motor. Features soft-start (creates less motor stress and reduces start-up torque), a carbide brake stop (so you can quickly change discs or set the sander down the instant you’re done sanding), an electronically controlled vibration dampening system that makes for smoother sanding, as well as stepless variable speed control from 6,000 to 10,000 RPM, rocker-type power switch, constant speed underload, and thermal and overload protection. Includes Festool’s JetStream system, which reduces heat build-up on the sanding disc, reducing clogging and prolonging disc life. Has an extra long 13′ power cord and a low-profile design that is especially comfortable to use, particularly for long periods of time. Sound level ranges from 67 dB (minimum speed) to 81dB (max speed). Connected to any dust extractor you get almost 100% dust-free sanding. Also available in the ‘EC’ line are two 150-mm/6″ models with 3-mm or 5-mm strokes.
Also called orbital, finish or palm sanders, they generally have a pad that takes a 1/4, 1/3 or 1/2 sheet of sandpaper, with the 1/4 size being the most popular. The pad typically moves in one direction only, removing material more slowly than ROS sanders. The resulting scratch pattern is very consistent. I find it beneficial to orient and move these sanders in the direction of the grain for best results. Because they are smaller and sand less aggressively, they’re very easy to use. They’re also less expensive to purchase. Some sanders take PSA or hook-and-loop paper, but most use simple metal clamps for attaching standard sandpaper you can cut to size or buy pre-cut. The shape of the base enables them to sand close to inside corners, and their small size makes them easy to control and useful for sanding narrow stock such as table legs, aprons and drawer parts. From $20 to $600.
The 2.0-amp motor with a dust-sealed power switch produces a constant 12,000 oscillations per minute (OPM) and delivers a super-smooth surface reasonably quickly. In use, there is practically no vibration, and the recorded sound level was 76 dB. The sander uses a standard metal clamping system that is quick to adjust and holds paper securely. It also accepts PSA-backed paper. The microfilter dust canister is surprisingly effective, and you can also connect a 1-1/8″ I.D. hose for use with a dust extractor. An integrated paper filter in the canister traps particles as small as .5 micron. With the soft-grip handle directly over the motor the sander is very comfortable to use with one hand and has very good balance, making the sander easy to control. A good choice for fine sanding corners, edges, narrow stock and refinishing projects.
These come in a few styles. Those similar to sheet sanders but with triangular pads (sometimes called corner sanders) are typically geared to DIYers and hobby woodworkers. Those with an oscillating head and an elongated body (often called oscillating multi-tools) are geared to tradespeople, renovators and cabinetmakers. Both styles are ideal for reaching into tight spots inaccessible to conventional sanders, such as drawer and cabinet corners, for sanding small, narrow stock, and for sanding trimwork and molding. Some come with interchangeable heads for use on concave and convex surfaces. They use either PSA or hook-and-loop paper. From $35 to $525.
Detail Palm Sander
Weighs only 2 pounds, and the 1.2-amp motor develops a speed of 26,000 OPM. Low vibration and a comfortable rubberized grip. Doesn’t come with a dust canister, but has a dust port adapter for connection to a dust extractor. Comes with a two-year warranty.
Fein AFMT 12QSL
A cordless version of the world’s best-selling oscillating multi-tool, powered by a 12V 2.5Ah battery, weighing only 3.3 lbs. Delivers 11,000 to 18,000 OPM. Features the unique StarlockPlus tool mount with outstanding torque transfer. Precision sanding in the tightest of spaces. Its vibration decoupling system provides outstanding vibration and noise reduction. Has optional accessories for a wide range of cutting, grinding, scraping and polishing tasks.
Festool LS 130 EQ
A unique straight-line sander that has interchangeable pads for flat, concave and convex sanding. Powered by a 2.2-amp motor that delivers 4,000 to 6,000 OPM. Well balanced and weighs just under 4 pounds. Takes the common 80-mm × 133-mm Festool hook & loop abrasives. Takes an optional dust bag or connects to dust extractor with dust hose.
Contour Random Sander
This is an accessory that is particularly useful for turners and carvers. It fits onto any standard angle grinder, converting it into a random orbital sander. The 2-1/2″ shaft enables you to reach deep hollows. The backing pad flexes at the edges so you can sand over corners, into tight concave spaces and over convex edges without burning the wood. Takes 50-mm/2″ PSA discs from 80-to 600-grit.
Ideal for removing large amounts of material very quickly, for leveling wide and long surfaces and for shaping larger curves. A popular choice among carpenters, flooring and cabinetry installers, deck builders and the like. The most common take abrasive belts from 3″ × 21″ to 4″ × 24″. Can be single speed or variable speed, up to around 1,600 ft/min and have manual or automatic belt tracking. Some have soft start or offer optional sanding frames that help reduce inadvertent surface gouging. From $70 to $350.
The 8.8-amp motor drives the 3″ × 21″ belt on this 9.5 lb. sander at a variable speed rate of 690 to 1,440 ft/min. Features comfortable front and side grip handles, auto-tracking with an easy-to-use belt-tensioning lever, fabric dust bag with excellent dust collection and long 16′ power cord. Very good vibration control with an 85-dB noise level. You can sand flush against surfaces on the right side of the sander.