Setup Guide: Contractor Blast Machines

Watch how to set up and begin operating Clemco's Contractor Abrasive Blast Machines. Clemco designs its Contractor Blast Machines to be rugged, mobile, easy to operate, and simple to maintain. They come with 4-cuft or 6-cuft pressure vessels. Clemco is the world's largest manufacturer of air-powered abrasive blasting equipment, including abrasive blast machines, blast cabinets, blast rooms, safety equipment and blasting accessories.

Welcome to the Clemco Setup Guide for Contractor Blast Machines


This video outlines how to set up and then begin operating Contractor Blast Machines. It covers:

    • Preparing the Worksite & a Contractor Blast Machine
    • Preparing the Blast Hose & Remote Control Hose
    • Connecting the Compressor
    • Starting the System

Note that this video is not a replacement for reading the Contractor Series Blast Machine Operations Manual, which should be read in full by anyone who uses these machines. Failure to comply with the instructions in the operations manual can result in severe injury or even death.

Contractor Blast Machine and an Air Compressor

Preparing the Worksite

  • When setting up the equipment at the worksite, take note of the direction of the wind and be sure to locate the air compressor up wind of the blasting operation. This precaution helps prevent contaminated air from entering the compressor intake.
  • Sometimes the pop-up valve can shift during shipping. Check the alignment of the pop-up valve to ensure that when it is activated, it will be centered on the pop-up seat. If the pop-up valve is not properly aligned, it could prevent the machine from pressurizing.

Preparing a Contractor Blast Machine

  • Make sure the choke valve is open.
  • Check that the abrasive metering valve is closed.
  • Make sure the safety petcock located on top of the inlet valve is open. This will prevent accidental activation of the blast machine.
  • Install the optional moisture separator to the inlet valve. Clean, dry air is essential to an efficient blasting operation. Moisture in the air supply will likely cause media to clump and stick together, blocking the metering valve.
  • Install an air-supply hose coupling at the blast machine inlet piping. Make sure it is compatible with the compressed-air supply hose that connects the compressor to the compressed-air filter.
Installing a Moisture Separator: Contractor Blast Machine
Uncoiling twinline hose. Connecting blast hose: Contractor Blast Machine

Preparing the Blast Hose & Remote Control Hose

  • Uncoil the blast hose and lay the twinline hose alongside it. The hoses should be of equal lengths.
  • Band the RLX control handle to the blast hose close to the nozzle holder using the two nylon ties provided. After the control is firmly attached, clip the tie ends so that they do not snag the operator’s clothing or interfere with the operation of the control handle.
  • Attach the twinline hose to the two fittings on the back of the control handle. Either side of the hose can be attached to either fitting.
  • Working from the control handle back, band the twinline hose to the blast hose every 4 to 6 feet.
  • Make sure the coupling gaskets are in place and in good condition before connecting the blast hose to the quick coupling on the blast machine.
  • When connecting the blast hose with Nylon couplings, make sure the coupling spring lock pins are at 180 degrees. (The pins should enter the open hole of the adjoining coupling.) The spring lock pins prevent accidental separation of hose couplings during blasting.
  • Attach the ends of the twinline hose to the two lower adaptors in the fittings on the front leg. Either side of the twinline hose can be attached to either fitting.
  • Uncoil the breathing hose between the blast machine and where you’ll be blasting.
  • Connect the breathing hose to the top adaptor in the fittings on the front leg and then connect the other end to your blast hood or climate control device.
  • Place the nozzle washer in the nozzle holder and screw the nozzle into the holder. The nozzle must seat tightly against the nozzle washer.
  • Unroll the air-filter supply hose and connect it to the CPF filter.
  • Remember, OSHA requires that Grade D breathing air be supplied to the CPF filter and a CO monitor be used to monitor the air being supplied to the respirator.

Connecting the Compressor 

  • Connect an air-supply line from the compressor to the air-hose connector previously installed on the blast machine’s inlet filter.
  • Check that all compressed-air supply hose connections are secured with a safety cable to prevent accidental separation or disconnection.
Connecting Compressed Air: Contractor Blast Machine
Adding Abrasive. Adjusting the CPF Filter: Contractor Blast Machine

Starting the System

  • Operators and anyone else who may be exposed to the hazards generated by abrasive blasting must wear appropriate protective gear, including abrasive-resistant clothing, leather gloves, eye and hearing protection, and a NIOSH-approved Type-CE supplied-air respirator.
  • Close the air valve on the compressor. Start the compressor following the instructions that came with it. Allow the compressor to warm up to operating temperature and pressure. The pressure must be more than 50 PSI, but no more than the blast machine’s rated pressure.
  • Slowly open the compressor air valve to pressurize the air-supply line. Listen for noise that indicates any open lines or leaks.
  • Load the abrasive into the blast machine by pouring the abrasive into the concave head. Use the optional screen to prevent foreign objects that may jam the machine from entering the pressure vessel.
  • Keep the abrasive level below the pop-up valve to prevent abrasive from being forced up and out of the machine when it pressurizes.
  • Make sure the remote-control handle lever is in the up (no blast) position.
  • When you are ready to start the system, close the safety petcock. This allows the blast machine to be activated by the remote-control handle.
  • Air escaping from the control handle indicates that the blast machine is ready to be activated.
  • Adjust the pressure on the CPF filter according to your supplied-air respirator’s operating instructions.
  • Adjust the metering valve for your application. Begin with the knob set at 1-1/2 turns from fully closed and then turn it no more than a quarter turn counterclockwise to increase abrasive flow. Allow 10 to 15 seconds for the flow to stabilize before readjusting.
  • The system is now ready to begin blasting.

Correct operation of Clemco’s Contractor Blast Machines is necessary to protect blast operators and others in the vicinity of the machines from blasting and inhalation hazards that can cause severe injury or even death. The purpose of this video has been to familiarize viewers with how to correctly set up and then begin operating Contractor Machines. However, this video is not a replacement for reading the Contractor Series Blast Machine Operations Manual, which should be read in full by anyone who uses a Clemco Contractor Blast Machine.