Shop vac vs dust collector for a garage shop

• Your garage is a 12 x 20 ft one-car bay with a car in it. In our layout engine a shop vac with a separator is the one dust solution that fits beside a parked sedan in every bay, including the smallest. The 20 x 20 ft and larger bays take either.
• You run one tool at a time and you are always holding it. A random orbit sander, a router, a track saw and a miter saw all connect to a vac hose. The tool moves, the hose follows, and the vac comes on with a tool-triggered outlet.
• You have a single 120V outlet and a dedicated circuit is not on the list. A vac is a plug-in tool. See the workshop amps calculator to check that the vac and the tool together stay inside the circuit.
• You do not want to build ductwork. A vac needs a hose and a cart. A collector needs a plan.

• You own a stationary machine that throws chips. A planer asks for about 400 CFM at the hood, a table saw or a bandsaw about 350, a sander about 550. Those numbers are from our machine table. A shop vac is built to give suction, not that kind of volume, and its small hose is the limit.
• You work for hours. A collector has a 20 gallon drum, a canister filter and a cleaning paddle. A 12 gallon vac fills fast on planer chips and its filter blinds quickly without a separator.
• You have a 20 x 20 ft bay or a 12 x 22 ft one-car bay. In the 12 x 22 ft bay the G0860 fits with a sedan parked beside it, in our layout engine. It does not fit the 12 x 20 ft bay with a car.
• You want a dust system that you do not have to attend. A 6 in main with blast gates and a remote switch means you walk to the machine, open one gate and turn the collector on from your pocket.

Yes, with limits, and the limits are about air volume rather than power. Dust is carried away from a cut by a stream of air with enough speed to keep chips moving, about 4,000 feet per minute in a duct. The volume of air at that speed is the cross-section area of the duct times the speed. A 4 in duct at 4,000 fpm is 349 CFM, a 6 in duct is 785 CFM. A shop vac hose is far smaller than a 4 in duct. By the same velocity times area formula, a 2-1/2 in hose carries about 136 CFM at 4,000 fpm. That is below the 350 CFM a table saw hood asks for in our machine table.

A shop vac makes up the difference with suction. It pulls hard through a small opening, which is what you want for a sander port or a router shroud, where the opening is small. The vac works well when the tool's own dust port is the choke and the tool throws fine dust. It works badly on a machine with a big open hood and heavy chips, because there is nothing to hold the chips in the airstream.

We did not test any vac. The figures here are from the manufacturer listings and published formulas; the DEWALT 12 gallon and the Shop-Vac Ultra Quiet 12 gallon both list a 5.5 peak HP rating and nothing else we can compare to a collector's CFM. Peak HP is not an airflow figure.

A vac's filter is its weak point. Fine dust packs the filter in minutes and suction falls away. A cyclone separator such as the Dust Deputy Low-Pro Plus sits between the hose and the vac and drops most of the dust into its own bucket before it reaches the filter. The vac then stays at full suction for much longer, and you empty a bucket instead of cleaning a filter. If you plan to use a vac for dust collection at all, buy the separator first; it is the cheapest upgrade in this comparison.

A separator does not add airflow. It protects the filter. The vac with a separator is still a handheld-tool system, and the right way to think about it is as a mobile station: one hose, one tool, one gate. Our sizing page for tight bays says the same thing, as the fallback when the collector itself will not fit; see the dust collector sheet for a 12 x 20 ft garage.

Our layout engine placed each option alone in each bay, with and without a sedan.

The vac's footprint is an allowance of 18 x 18 in in the engine, a planning number rather than a measured one; check the listing for the model you buy. The G0860's footprint is 27-1/2 x 44 in on its listing, 70 in tall, and the sheet for all six bays is the G0860 fit sheet.

The bigger difference for a car is dust control after the cut. A collector with a 1 micron canister keeps fine dust out of the air that settles on paint. A vac with a good filter does the same job at its own scale. Neither replaces a hanging filter: see the air filtration roundup.

A shop vac plugs into any 120V outlet. The G0860 is listed at 15 A at 120V; 125 percent is 18.8 A, so it gets its own 20 A circuit with 12 AWG copper, per NEC Table 310.16. A licensed electrician should confirm the circuit. A vac running on the same circuit as a router and a table saw trips the breaker, so the question for the vac is also how many tools are on the circuit.

Noise is where the vac loses. A vac's motor is a universal motor that turns very fast, and the sound is a high whine that carries through a garage door. The Shop-Vac model in our catalog is marketed as ultra quiet, but the listing is the place to read the number. The G0860 lists 78 dB. Either way, wear hearing protection such as the Decibel Defense 37 dB NRR muffs and shut the door if the neighbors are close.

A collector with a wireless remote, as listed for the G0860, helps in a different way: you do not run it longer than you need to.

A vac and a separator are inexpensive, and the tier of each is in the table above, not a quote. A collector costs more, adds a duct system, and may need a circuit. The cost that matters is the second purchase. A woodworker who starts with a vac and adds a planer buys a collector within the year; one who starts with a collector and never adds a stationary machine spent too much. Decide by the machine list, not by the budget alone. The dust collector calculator turns your machine list into a CFM requirement and tells you whether a vac can serve any of it.

The two can live together. A common arrangement in a two-car garage is a collector on the stationary machines and a vac on the miter saw, the sander and the floor. The vac also serves the car: it is the thing you use to vacuum the shop before the car comes back in.

Fine wood dust is a health hazard, and neither machine is a substitute for a respirator. Wear a respirator rated for fine dust, for example the GVS Elipse P100, when you sand or cut. Dust is also a fire and explosion risk in a closed collector; keep ignition sources such as grinder sparks away from the collection system, and never vacuum hot embers. A shop vac used for wet cleanup should not be used for dry dust without checking the filter type on the listing.

A vac with a separator for handheld tools and a 12 x 20 ft bay; a cyclone collector for any stationary machine. The G0860 is the smallest cyclone in our set that fits a one-car garage with a car in it (the 12 x 22 ft bay), and it runs on a 120V circuit. The vac is the right first purchase for a tool-by-tool workshop. If you plan a table saw, a planer or a jointer, skip the middle step and buy the collector. See the dust collector roundup and the G0860 against G0441 page for the next step up.