Best Random Orbital Sanders

Buying guide for Best random orbital sanders

A random orbital sander is a versatile tool capable of handling dozens of different jobs quickly and efficiently. They're not expensive, and they're easy to use. With a little practice, anyone can sand like a pro using a random orbital sander.

Not surprisingly, these tools are very popular, and there is an enormous number to choose from. Deciding which one to purchase is no easy task. The fact that one looks much like another and that specifications can sound very similar doesn't help.

With the correct abrasive, a random orbital sander can be used to sand metal, plastics and composites, too.

Why buy a random orbital sander?

There are lots of different sanders around, from small-detail sanders designed to get into tight corners to big sheet sanders used to finish large areas. Each of them is function-specific.

Where a random orbital sander scores is its versatility. It's a great all-rounder, useful for everything from stripping old paint off a door to fine-finishing a piece of furniture. While it can't quite get into the tightest spaces that a detail sander can manage, it can handle just about everything else.

The complex elliptical and rotary action – that "random orbit" – has two benefits. With coarse sandpaper, it can remove material very quickly. With finer grits, it's comparatively easy to get a smooth, professional-looking finish.

A random orbital sander is, in effect, whatever kind of sander you want it to be – and they are extremely popular as a result.

Random orbital sander considerations

An initial look at random orbital sanders shows several similarities. With the exception of a few commercial models, almost all have a 5-in. diameter sanding pad. The majority also use a hook and loop attachment which makes it quick and easy to change sanding discs.

So what are the differences? What do the best random orbital sanders offer that others don't?

There are three areas that separate one sander from another:

• Type of power

• Speed

• Additional features

Type of power

Random orbital sanders are either pneumatic, corded or cordless.

Pneumatic models are most often found in auto and truck body shops, where they're generally used in preparation before painting. They're light because there's no motor, but the movement is restricted because you need to use an air hose to connect to a compressor. Air hoses, while quite supple, are nowhere near as flexible as electric cable. If DIY auto repair is your thing, then a permanent set-up in your garage is worth considering—particularly if you have other air tools.

However, the majority of people want to be able to use their sander in the garage or shed and around the house. For those purposes, a corded or cordless random orbital sander is more appropriate.

Corded random orbital sanders are far and away the most common type available. Although the cord theoretically restricts movement, most manufacturers provide sufficient length so this usually isn't a problem. If you're likely to work with large sheet material on a regular basis, cord length is something you will want to check.

Cordless random orbital sanders at first seem the optimum solution, and they certainly offer great freedom of movement. But there are two negatives.

• The first drawback is the additional weight of the battery. It’s not too noticeable if you're working with the sander resting on top of the work, but it can soon become tiring if you're working on a vertical surface or above your head.

• The second drawback is runtime. Most cordless random orbital sanders are 18-volt, and runtimes are in the region of 20 to 30 minutes between charges. If you're sanding down an old door, half an hour goes by surprisingly quickly. You then either wait half an hour or more while the battery recharges, or you buy a second battery, and batteries aren’t cheap.

Speed

With coarse-grit sandpapers, high speed is good for rapid material removal. With finer-grit sandpapers, high speed allows you to produce an increasingly scratch-free (and therefore smooth) surface. Either way, you want plenty of speed. Most top random orbital sanders are rated between 10,000 and 12,000 rpm.

However, outright speed isn't always the best answer for every material, so several manufacturers offer adjustable speed. Sometimes this is just two or three switchable alternatives; other times, it's a fully variable speed dial.

There is some debate among woodworkers as to whether variable speed has much of an impact. Indeed, several major brands don't offer it. If you're looking for an all-around DIY sander, variable speed is probably not important. If you're working with expensive hardwoods (and expensive sandpapers) to produce mirror-like finishes, variable speed is definitely important.

Additional features

• Amperage: Corded random orbital sanders have motors from one to three amps. It doesn't usually impact the speed available, but it's reasonable to assume a more powerful motor is capable of working harder for longer. If you're looking for an occasional-use tool, amperage is of less importance. However, if you'll be doing a lot of sanding, we recommend a higher-rated tool.

• Dust receptacle: Sanders produce a lot of dust, and depending on what you're sanding, it can be unpleasant stuff. All random orbital sanders have some kind of dust bag or cartridge, and the efficiency of this unit should be considered. They do tend to fill up quickly, so it's going to get frustrating if a dust receptacle is difficult to remove and replace. Where possible, it's better to remove the receptacle completely and attach a Shop-Vac or other dust extraction system.

• Start-up control and braking: Running at a speed of up to 12,000 rpm can make sanders jerk quite violently, so some manufacturers offer start-up control. They might also offer motor braking when the trigger is released, so you don't have to wait for the sander to slow down.

• Grips and side handles: Most random orbital sanders are designed to be used with one hand. A variety of soft grip areas are provided. A few also have removable side handles, which can offer greater control and stability when working over large areas. Side handles are particularly useful if you have small hands and might otherwise struggle to grip the body of the sander.

• Vibration protection: Because of the sanding action, random orbital sanders do tend to vibrate quite a bit. Anything that insulates the user from this vibration makes the tool more comfortable to use, and less tiring.

Random orbital sander prices

Corded

A corded, entry-level random orbital sander from a well-known brand can be found for around $25. Even the very best entry-level models, complete with a nice bag or case to carry it in, can be yours for less than $100.

Cordless

Cordless random orbital sanders are widely available, but they cost considerably more. Advertised prices initially seem similar to corded versions, but they frequently don't include the battery. That can add $40 to $70 to the price, making some cordless models twice the price of their corded counterparts. Typically, you'll pay more than $100 for these.

Pneumatic

Pneumatic random orbital sanders—those that require an air compressor to operate—are generally only found in auto body shops and similar establishments. Depending on size and specification, they can cost anywhere from $30 to several hundred dollars. It's not unknown for auto enthusiasts to have this kind of equipment at home, but corded electrical models are more portable, easier to operate, and much more popular as a result.

A random orbital sander is one of those tools that should be in every home toolbox. Fortunately, adding one to your collection won't break the bank.

Tips

• In general, you should turn on your sander and let it reach full speed before beginning work. When rough-sanding large boards or panels, some woodworkers do start a sander with it resting on the surface. Be aware, though, that the tool has a tendency to twist when it is first turned on.

• Similarly, you should let your sander stop naturally and away from your work. Never stop it by holding it against the work piece. The sander could snag—which isn't safe, but the main reason for this is to protect your work. You'll put scratches back in that you've just spent time removing!

• Pre-punched sanding sheets can be expensive. You can save money by buying hook-and-loop-backed sandpaper on a roll and cutting your own. You will need a punch (many woodworkers make their own) to make holes to allow for dust removal. Without them, dust quickly builds up between the sandpaper and the sander's hook and loop pad, causing the disks to fly off.

Sander bags and filters need to be emptied or cleaned frequently, which can get frustrating. Attaching a Shop-Vac or dust extraction system will allow you to work for longer without interruption.

FAQ

Q. What's the difference between a random orbital sander and a palm sander?

A. A random orbital sander is a medium-size, general-purpose sander. Depending on the sandpaper chosen, it can be used for rapid material removal or fine finishing. A palm sander (also called a finish sander) may have a similar action to a random orbital sander, but it is much smaller and only used for finishing.

Q. What do the numbers on sandpaper mean?

A. Grit numbers show the size of the particles that do the cutting/sanding. So, 60-grit sandpaper has large particles and is thus a coarse paper used for initial rough sanding. Medium-weight sandpaper is 150-grit, and 240-grit is fine. The full range runs from 16 grits (extremely coarse) to 2,000 grits (extremely fine), though woodworkers seldom use anything higher than 320 grits.

Q. Is sandpaper actually made with sand?

A. Although sand was originally used in the production of silicon carbide, an abrasive that's been around for 100 years and remains popular, that's no longer the case. The most common sandpaper among woodworkers today is aluminum oxide. It's cheap and long-lasting. Zirconia alumina and ceramic alumina are also used and are very effective, but these varieties cost considerably more.