I have had the 6″ Mirka CEROS (Compact Electric Random Orbit Sander) for about a year. Although I have not used it in a production shop environment, I used it extensively for sanding sculptural work and, to a lesser degree, for flat surfaces. I have had absolutely no issues with it.
When I purchased the Mirka CEROS, it was only available as a 5″ or 6″ sander with a 5 mm orbit. The 5 mm orbit is for general work. Since then, Mirka has released two more 6″ CEROS models – one with a 2.5 mm stroke for finish sanding and one with an 8 mm stroke for more aggressive sanding. I do not believe these are currently available in North America.
The sanding action is very smooth and the DC motor is powerful and reasonably quiet (68 dB, which is similar to a piano practice). It is lightweight and well-balanced, making it comfortable to use with either one hand or two. The power cord is quite flexible and permanently attached to the sander. Mirka sells a hose for the sanders, which is more flexible and lighter (for improved ergonomics) than the Festool Anti-Static D27 hose. The Mirka CEROS has a round dust port with female threads to accept a 1-1/4″ diameter threaded hose.
Although the Mirka sanders closely resemble pneumatic ones, they are powered by a maintenance-free, brushless DC motor and do not require a large air compressor. The sanders have a 14′-long power cord that plugs into one end of a 8-1/2″ x 5-1/2″ x 3-1/4″ transformer. A 6′-long power cord runs from the other end of the transformer into a standard AC outlet.
The Mirka CEROS is available with either a 125mm (5″) or 150mm (6″) diameter pad. The smaller sander weighs 870 grams (1.9 pounds) and the larger weighs 920 grams (2 pounds). I think the 6″ version is more practical not only because it can sand a larger area more quickly, but because the larger pad has a greater distance between the edge of the pad and its body which is useful when working in tight quarters.
The speed of the sanding pad can be adjusted from 4,000-10,000 RPM in 1,000 RPM increments using the buttons on the top-rear of the sander. Between the speed control buttons is a power button for safety to prevent the sander from starting accidentally. The paddle switch on top is pressed and held down to operate the tool. By feathering the paddle, you can control the speed as well but it is very sensitive and not a very reliable way to run the sander at a lower speed. Instead, it functions as a soft-start feature, of sorts.
One addition that I would like to see is a pad brake. After releasing the paddle switch with the pad turning at 10,000 RPM, the pad continues to spin for about 19 seconds.
This first video explains and demonstrates some of the features of the Mirka CEROS. (Duration: 10:19.)
(Note: Since recording this video, a reader has pointed out that the CEROS set to run at the lowest speed will indeed draw enough current when under load to run a Festool Dust Extractor set to auto-start.)
In these two posts, you can read more about how I:
- combined the Mirka CEROS’s transformer with my Festool CT26 Dust Extractor; and
- modified the Festool D27 hose’s tool end to fit the Mirka CEROS’s dust collection port.
This second video is a demonstration of the Mirka CEROS. In the first part, I sand the flat top of a bench with 80, 120, 180, 220, and 320-grit Abranet discs. In the latter part of the video, I demonstrate how I sand contoured parts with and without the foam interface pad. (Duration: 13:43.)
Consider this sander because it:
- is powerful and easy to control;
- runs quietly and smoothly;
- feels good because it is compact and well-balanced;
- requires very little maintenance because it has few wearing components; and
- does not require a large air compressor to run (as a pneumatic sander does).
The Mirka CEROS comes with a 3-year warranty. You can download the warranty information as well as manual from the Mirka CEROS website.
Also, check out the Abranet abrasive discs made by Mirka. The discs last a long time and don’t require alignment of any dust collection holes. I would recommend getting the 80-, 120-, and 180-grit sanding discs as well as a Pad Saver (I called it a platen protector in the video). If you work with non-flat surface, I would also recommend looking at the 10 mm (3/8″) Multi Interface Pads
- Ultimate Tools in Burnaby, BC carries the Mirka CEROS, Abranet, Pad Savers, Multi Interface Pads, and Hose
- Lee Valley Tools carries Abranet, Pad Savers, and Multi Interface Pads.
- Woodcraft carries the Mirka CEROS, Abranet, and Pad Savers.
(I do not receive any compensation for what I write and the list of suppliers is by no means an exhaustive one; I’ve simply listed some to get you started.)
Mirka Part Numbers
- MIM5502011CA 125 mm CEROS, 5.0 mm Orbit
- 8295510111 125 mm (5″) 44-Hole Pad Savers (3 mm Thick), Pkg of 5*
- 8295500111 125 mm (5″) 44-Hole Multi Interface Pad (10 mm Thick), Pkg of 5*
- MIM6502011CA 150 mm CEROS, 5.0 mm Orbit
- 8295611111** 150 mm (6″) 57-Hole Pad Savers, Pkg of 5*
- 8295600111 150 mm (6″) 67-Hole Multi Interface Pad (10 mm Thick), Pkg of 5*