Orbital Sander

Owned by Michael Giannattasio
Last updated: Feb 01, 2021 by Andrew Molloy
6 min read

An Orbital Sander is a power tool used to smooth surfaces by abrasion with sandpaper. Orbital sanders have a means to attach the sandpaper and an electric motor to move it rapidly, contained within a housing with allows it to be hand-held and maneuvered across surfaces or edges to be sanded. In the SOA, we have three types of Orbital Sanders. One type uses round sanding discs that have a perforated “Velcro”, or “Hook and Loop” attachment method. Another uses round, adhesive-backed sanding discs, and the third type has a square, rather than round base, which uses ¼ pieces of standard sandpaper sheets. This third type is called a ¼ sheet sander, and will be described later in this document.

Safety

  • Use personal protective equipment. Always use certified safety glasses. Other protective equipment such as dust mask, non-skid closed shoes, or hearing protection used for appropriate conditions will reduce personal injuries.
  • Dress properly. Do not wear loose clothing or jewelry. Keep your hair, clothing and gloves away from moving parts. Loose clothes, jewelry or long hair can be caught in moving parts.
  • Keep work area clean and well lit. Cluttered areas invite accidents.
  • Keep bystanders away while operating a power tool. Distractions can cause you to lose control.
  • Keep the power cord away from sharp edges or moving parts of the machine. Damaged or entangled cords increase the risk of electric shock.
  • If devices are provided for the connection of dust extraction and collection facilities, ensure these are connected and properly used. Use of these devices can reduce dust-related hazards.
  • Do not force the power tool. Use the correct power tool for your application. The correct power tool will do the job better and safer at the rate for which it was designed.  
  • Do not use the power tool if the switch does not turn it on and off. Any power tool that cannot be controlled with the switch is dangerous and must be repaired.  
  • Disconnect the plug from the power source before changing accessories. Such preventive safety measures reduce the risk of starting the power tool accidentally.

Personal safety

  • Stay alert, watch what you are doing and use common sense when operating any power tool.
  • Do not use any power tool while you are tired or under the influence of drugs, alcohol or medication. A moment of inattention while operating power tools may result in serious personal injury.
  • Prevent unintentional starting. Ensure the switch is in the off-position before connecting to power source and picking up or carrying the tool. Carrying power tools with your finger on the switch or energizing power tools that have the switch on invites accidents.
  • Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations.
  • Hold tool by the insulated gripping surfaces when performing an operation where the sanding tool may contact hidden wiring or its own cord. Contact with a “live” wire will make exposed metal parts of the tool “live” and shock the operator.
  • Always maintain a firm grip on the sander, preferably with both hands to prevent loss of control.
  • Do not sand metal of any kind. Sanding screws, nails or other metals, which may ignite dust particles, may generate sparks.

        •      Do not wet sand with this sander. Liquids may enter the motor housing and cause electric shock.

  • Do not operate this tool for long periods of time. Vibration caused by the operating action of this tool may cause permanent injury to fingers, hands, and arms. Use gloves to provide extra cushion, take frequent rest periods, and limit daily time of use.
  • Always disconnect tool from the power source before changing abrasive discs or sheets. Such preventive safety measures reduce the risk of starting the power tool accidentally.

Operational Set-Up

Attaching Sanding Discs (FIG. 1)

The round-based sanders in the SOA are designed to use either 5"sanding discs with a “Velcro” or “Hook and Loop” sanding discs, or “PSA” (Pressure Sensitive Adhesive) sanding discs.

  • Velcro Discs have an 8-hole dust extraction pattern and hook & loop attachment to the sander pad.
  • PSA Discs have no holes, and are coated with an adhesive, which adheres to the smooth sander pad.

To attach Velcro-backed sanding discs to the “hook-textured” sanding pad style of sander:

  1. Turn off and unplug the tool.
  2. Turn the sander over so that the sanding pad is facing upward.
  3. Clean dust from the vinyl pad face.
  4. Hold the pad with one hand to keep it from rotating.
  5. With the other hand, align the holes if they are present, and place the disc directly on top of the pad.

To attach PSA-backed sanding discs to the “smooth-textured” sanding pad style of sander:

Repeat steps 1 through 5 above, however, there is no need to align holes in the PSA discs, since there are none.

Power Switch (Fig. 2)

To reduce the risk of injury, make sure the sander is not resting on the workpiece when the switch is turned on. To turn the unit on, depress the side of the dust protected switch that corresponds to the symbol “I”. To turn the tool off, depress the side of the switch that corresponds to the symbol “O”.

The Power Switch is the same on all three types of orbital sanders in the SOA.

Dust Extraction (Fig. 3, 4)

To reduce the risk of injury, turn unit off and disconnect it from power source before installing and removing accessories, before adjusting or when making repairs. An accidental start-up can cause injury.

Our Orbital Sanders all come equipped with a cloth bag to collect the dust generated during sanding. They are designed to be very durable and efficient yet easy to empty.

To Empty the Dust Collection Bag

  1. Turn off and unplug tool.
  2. While holding the canister,  twist to unlock and remove the adapter. (Fig. 3)
  3. Gently empty the bag and shake out the adapter. (Fig. 4)

Note: You may notice that all the dust will not come free from the bag. This will not affect sanding performance but will reduce the sander’s dust collection efficiency. To restore your sander’s dust collection efficiency, depress the spring inside the dust bag when you are emptying it and tap it on the side of the trashcan or dust receptacle. Never operate this tool unless the dust collector is in place. Sanding dust exhaust may create a breathing hazard.

Operation (Fig. 5, 6)

  • To operate your sander, grasp it as shown in figures 5 or 6 and turn it on.
  • Move the unit in long, sweeping strokes along the surface being sanded, letting the sander do the work.
  • Pushing down on the tool while sanding actually slows the removal rate and produces an inferior quality surface.
  • Be sure to check your work often, this sander is capable of removing material rapidly, especially with coarse paper.
  • The random orbital action of your sander allows you to sand with the grain or at any angle across it for most sanding jobs.
  • To produce the best finish possible, start with coarse grit sandpaper and change gradually to finer and finer paper.

¼ Sheet Sanders

The ¼ Sheet Sanders in the SOA are similar in function to the Orbital Sanders, but have square pads instead of round ones, so they can reach into corners. Lab Technicians must be consulted regarding set-ups for these.

Sand Paper Discs and Sheets

The Fabrication Labs provide Sanding Discs and Sheets for all of our sanding equipment.

The Sand Paper we provide comes in various “Grit Sizes” ranging from 60 Grit, which is very coarse, to 400 Grit, which is very fine. Sanding Discs are proprietary for specific equipment. However, standard sheets of sand paper are readily attainable for student purchase through our supply store in Slocum Hall, and can be used with our ¼ Sheet Sander or otherwise used by hand or made into sanding blocks with scrap wood.

Clean-up

When you are finished working with a Belt Sander, clean the area before leaving the workstation. There are 4 Trash barrels in this room, and each one has a broom, bench brush and dust pan attached. You must use these items to clean up your work areas at each machine, when you are finished working there. Also, there are scrap barrels at each workstation to deposit scraps of material, which may be useful for someone else. Please do not put materials with stray hardware or glue on them, or food/drink items, only re-usable materials.