Rupes Skorpio 6" Air-Powered Random Orbital Palm Sander

Rupes 6" Skorpio Palm Sanders feel righteous.  Ergonomic design characteristics combine with supreme engineering to deliver confidence-inspiring balance and control.

The Skorpio is a random orbital sander.
Skorpio Palm Sanders create two independent backing plate motions that work simultaneously to create a suberb sanding result.  Machines that carry a random orbital designation have been around for decades, and are typically used to refinish just about anything in need of sanding or polishing. Skorpio's backing plate moves in an orbital pattern that would be similar to the movement of your hand, if you happened to be brushing your teeth using tight and consistent circular motions.  An adjustable speed lever controls the quantity of orbits created by the Skorpio.

Skorpio's backing plate is able to spin clockwise or counterclockwise, and at a random rate.
Skorpio's dual action design combines random rotation of the backing plate with a motor-driven orbital motion to create a finish that is hard to duplicate via hand sanding. If you were to grab ahold of the Skorpio's backing plate and give it a flick in either direction, the backing plate would free-spin, eventually coming to rest. As you fire up the Skorpio, its motor force-drives the backing plate along an orbital path. Dynamic factors including speed, pressure, friction, bearing load, and orbit size combine to determine the frequency and direction of backing plate rotation.

Skorpio Palm Sanders are available in three stroke variations.
In order for the backing plate to move along an orbital path, its mounting pad is placed off-center in relation to the machine's driveshaft.  This distance is typically measured in millimeters or inch-fractions.  Therefore, a machine that features an offset of 3mm creates an orbit diameter of 6mm.  Skorpio sanders are available in 3mm, 6mm, and 9mm stroke diameters.

"Which stroke diameter should I use?"
While short stroke machines have traditionally been recommended for tasks requiring the use of very fine sanding discs, and large stroke machines for coarse sanding discs, my research and testing indicates this to be a huge misconception.  If you're still unsure of which offset would be ideal for your sanding task, do not hesitiate to call or e-mail for a recommendation.

In general, a machine featuring a small or short stroke confines its sanding to an area smaller than that of a large stroke machine. Additionally, since there is less lateral motion of the backing plate, it can more readily fit into tight or confined areas. There are several obvious and not so obvious advantages to using a small stroke machine.

A machine featuring a large or long stroke will generate more backing plate rotation than an identical short stroke machine. Although increased rotation can increase cutting speed, it may also create longer scratches atop the sanding surface if the sanding disc is loaded with debris. Further, if the machine is inadvertently or aggressively tilted during use, a large stroke machine can create deeper gouging atop the sanding surface.  Large stroke machines will also sand a larger area per orbit; however, sanding along the outlying areas will not be as thorough as the area directly below the machine.

Use a 3mm diameter stroke machine:
   As recommended by Rupes:
• For fine-grade sanding (P320-P5000)

   My recommendation:
• On delicate items that cannot handle vigorous movement of the backing plate
• In confined areas, or on parts that will not physically allow the use of a machine
  with a medium or large stroke
• When high-speed rotation of the backing plate is not desirable

Use a 6mm diameter stroke machine:
   As recommended by Rupes:
• For medium-grade sanding (P100-P320)

   My recommendation:
• For most sanding duties (this is the most popular stroke size for 6" discs) 
• On items or parts that can handle somewhat vigorous movement of the backing plate
• On areas that will physically allow the use of a machine with a medium stroke
  (in reference to backing plate movement)
• If you plan on using the machine as a polisher (outfitted with very thin buffing pads)
• If you desire more rotation of the backing plate than a 3/32" machine can deliver

Use a 9mm diameter stroke machine:
   As recommended by Rupes:
• For coarse or aggressive sanding (P060-P120)

   My recommendation:
• On items or parts that can handle vigorous movement of the backing plate 
• On areas that will physically allow the use of a machine with a large stroke
• If you plan on using the machine as a polisher (outfitted with thin buffing pads)
• If you desire substantial rotation of the backing plate
• If all the above applies, and you understand the benefits of using a large stroke machine

Still not sure which machine suits your needs, or want to learn more about stroke diameter?
Read about stroke diameter here.  You can also e-mail or call us for a recommendation.

 Add a spare backing plate, save 15%. 
Better to be safe than sorry!  Having a spare backing plate on hand is always smart.  The Rupes 981.500 6" Velcro Backing Plate is a direct replacement for the factory installed unit.

 Add an interface pad, save 15%. 
By placing an interface pad between the sanding disc and backing plate, sanding discs will more easily conform to curved or complex surfaces.  Should you inadvertently add excessive tilt to the machine, an interface pad will help to distribute pressure across the entire face of the disc. 1066 | 1066F  | 1066SF | 9166 | S6FI | 981.460