The Content Of The Article:

An alternative source of energy, compressed air makes it possible to operate pneumatic tools to clean, grease, chisel, paint, sand, polish, screw... This energy is obtained by means of an electric or thermal motor compressor that drives one or two pistons charged with sucking and compressing the air before sending it to a storage tank.

Criteria of choice for the purchase of a compressor

Description of an air compressor

Description of the air compressor

01Storage tank
02Pressure gauge of service
03Pressure gauge tank
04Filter purifier
05Compressed air outlet
06Service pressure adjustment
07Pressure switch
08Electric motor
09Drive belt
10Compression pump

Pneumatic tools used

Spray gun

Spray gun

Joint gun

Joint gun





Impact wrench

Impact wrench





Stapler, nailer

Stapler, nailer

How to choose a compressor?

choose a compressor

  • The first criterion of choice, when one wishes to buy a compressor, is the air flow restored. The higher it is (liter / min or m3 / h), the greater the possibilities.
  • The power of the engine and the number of pistons are themselves determining the suction speed.
  • The capacity of the tank affects the work continuously.
On average, the powers range from 2 to 4 HP and the most used tanks contain 50 to 100 liters.
  • With 50 liters, you can clean, inflate, staple, nail and do small painting jobs.
  • With 100 liters, you also have the possibility to sand, chisel and paint large areas.
On some devices, the applications are clearly indicated, as at Mécafer.
Remains the price which can, according to the performances, vary from 150 to more than 1 000 €.

Getting started with the electric compressor

electric compressor

The most common models use an asynchronous electric motor.
The power is expressed in CV or kW.
The belt system makes it possible to have an independent motor and good ventilation of the compression head.

Getting started with the nomadic compressor

nomadic compressor

Equipped with a handle and four wheels, this 100 liter compressor with the full tank weighs nearly 85 kg.
It is not very easy to move in the garden, but it is possible to equip a wall hose reel or an extension.

vertical shaft compressor

Vertical tank compressors are more convenient to move and store.

Filling the tank

Fill the tank with an air compressor

The pistons suck the ambient air and then send it through a rigid or flexible conduit, into a buffer tank where it rises in pressure up to 8 or 10 bar. The tanks have a storage capacity of 10 to 200 liters.
On this model, the tank is 100 liters with a return air flow of 320 l / min.

Pressure controllers

Check the pressure of a compressor

The compressor is equipped with two manometers.
The first indicates the air pressure of the tank.
The second allows to adjust the operating pressure, different from one tool to another.
The pressure level can be adjusted using the wheel located above it.

Air purifier filter

compressor filter

The ambient humidity sucked by the compressor or the condensation present on the wall of the tank produce moisture at the outlet of the tank.
This can disrupt paint work and oxidize the mechanism of pneumatic tools.

draining a compressor air purifier filter

This model is equipped as standard with an air purifying filter that is drained.
Otherwise, it is an accessory that can be connected to the outlet of the pipe.

Compressor activation and maintenance

maintenance of a compressor

The connection
The compressed air is returned via a flexible hose that connects with quick couplings on the compressor and pneumatic tool.
The tip of the hose must be fully engaged in the compressor fitting to unlock the ball that closes the passage of air.
Hoses are not supplied, but can easily be found in GSB or on the Internet.


flexible hoses for compressor

They exist in different diameters and qualities to best withstand pressure and heating.

  • Nylon 6 to 8 mm internal diameter for 8 to 10 bar maximum pressure.
  • Made of reinforced nylon 8 to 12 mm in diameter for 10 to 15 bars max.
  • For a blower or an inflator, a diameter of 6 to 8 mm is sufficient.
  • For an impact wrench, chisel, stapler or spray gun, it is better to choose a diameter of 10 to 12 mm.

The start-up

start a compressor

After connecting the unit to the mains, simply turn the knob on the pressure switch block.
Then it's the pressure switch that manages. It switches off the engine as soon as the maximum pressure of the tank is reached (in this case 10 bars) and switches it back on when the pressure drops between 4 and 7 bars.
Once the tank is full, the compressor can also be used unplugged.

Cleaning the air filter

clean the filter of a compressor

The air is sucked at each descent of the piston and then discharged to the storage tank at each ascent.
Valves prevent air from coming out.
At the intake, the air passes through a filter that eliminates impurities.
Easy to access, it must be checked and cleaned regularly.
You can connect a blower to the compressor for cleaning.

The oil level

monitor the oil level of a compressor

Oil is vital for the life of the crankshaft and pistons.
Before and after each use, it is advisable to check its level.
The gauge is located at the bottom of the crankcase.
Note that some models (Mécafer) operate without oil.

The emptying of the tank

empty the tank of a compressor

The steel tank is sensitive to oxidation due to condensation and can deteriorate rapidly.
Under the tank, a drain plug allows to evacuate the water still present after use.

Common pneumatic tools

pneumatic tool: the chisel

Pneumatic tools like the chisel, the impact wrench, the sanders... are as efficient as their electric counterparts.

air flow and operating pressure of a compressor

Air flow and operating pressure are indicated on the tool or packaging.

lubricate a pneumatic tool

The mechanism Pneumatic tools must be lubricated regularly.
On this impact wrench, the oil is introduced through the air inlet.
It is possible to equip an oiler coupled to a wall air purifier.

put teflon on the connections of a compressor

The tools are delivered with the air connection disassembled.
Before screwing it on and to prevent any air leakage, fill the thread with two Teflon towers.
The installation of this one is in the opposite direction of the screwing, from the right to the left.

Blower and inflator

blow gun and pressure gauge inflator

Two tools are essential with a compressor: the blower and the inflator with manometer.
The first is ideal for dusting tools and mechanical parts and the second for controlling the pressure of car and bike tires.
A fitting set can inflate pneumatic mattresses, small pools, balloons...

Orbital sander

orbital sander

The orbital sander is commonly used by bodybuilders.
Some sanding phases are done by wetting the abrasive.
With compressed air, there is no risk of electrocution.
The vibrating sander is also very practical in pneumatic version.

Air consumption

If the tool used consumes more air than the capacity of restitution of the compressor, this one empties more quickly and lowers the pressure. It is then necessary to wait for the filling of the tank to resume work.
The table below provides information on the consumption and operating pressure of the most commonly used tools.

Pneumatic toolsOperating pressureAir consumption
Sander2 to 6 bars300 l / min
Spray gun3 to 4 bars200 to 330 l / min
Grease gun4 bars250 l / min
Joint gun4 to 6 bars100 l / min
Blow4 to 6 bars150 l / min
pump4 to 6 bars150 to 230 l / min
Nailer stapler4 to 7 bars100 l / min
chipper6 bars140 l / min
Impact wrench6 bars250 l / min

Video Instruction: How to Maintain an Air Compressor