Test winner in the AUTO BILD polishing machine comparison: Kunzer 7PM05
The 7PM05 rotary press from Kunzer was the test winner in a practical comparison. With top values in the disciplines of use and effectiveness, the device was the only device to receive the rating “highly recommended” from the experts, achieving 166 out of 200 points.
Price-performance winner Einhell CC-PO1100
The two polishers SPTA 150 and Krauss Superpolish P7, with almost the same number of points, ended up in second and third place with the grade “recommended”. For places four and five, the test professionals also gave the rating “recommended” – with minor cutbacks in performance – for DeWalt DWP849X and Einhell CC-PO1100, the price-performance winner. In sixth and seventh place were the significantly “lacker” rotary polishers Tectake 400176 and Skil 9955MA. Far behind in last place was the Ferm AGM1084P machine, which can only be “conditionally recommended”, which was not convincing in terms of handling and effect.
How AUTO BILD tested it
The test comprised a total of twelve individual ratings in the four chapters of equipment, application, effect and costs. Individual polishers already made avoidable weaknesses in the operating instructions. SPTA, Krauss and Ferm provided little or no information on how to work with the devices. For a good polishing result, it is important to be able to vary the speed on the one hand. And on the other hand, the speed should remain constant even when working under high pressure. To our satisfaction, only the three best in the test managed this: Kunzer, SPTA and Krauss, who also scored points for start-up behavior and smooth running.
For effective work on the vehicle sheet metal, the devices should have sufficiently long cables. Except for Einhell, with a short 2.10 meters, all deliver lengths of four to five meters. The effectiveness test ultimately decides how evenly and clearly the polishers bring the paintwork of the test vehicle to a high gloss. Here, in addition to the subjective assessment based on visual inspection, an optical measuring device is used to determine the degree of gloss and haze. The testers only certified Kunzer, DeWalt, SPTA and Krauss as having really good performance. Ferm, Skil and Tectake showed weaknesses.
Our test partner: GTÜ is the abbreviation for “Society for Technical Monitoring” and our partner for the polishing machine test. GTÜ is known to most motorists as a motor vehicle inspection organization. The GTÜ inspectors appraise classic cars to issue a classic car number plate, check the roadworthiness of cars, stick the sticker on if the HU has passed or carry out the change acceptance after a vehicle tuning, just to show a few of the many fields of activity of the GTÜ. For our practical test, they tested the function and quality of eight polishing machines.
Conclusion on the polishing machine test
With good performance at manageable costs, the Kunzer 7PM05 polishing machine takes overall victory in the comparative test.
Polishing with a machine – this is something to consider
When polishing with a machine, the risk of polishing holograms into the paintwork is greater than when polishing by hand. Therefore always make sure that the machine remains in motion and never remains in one place. The polishing machine is guided crosswise over the surface. Start at a low speed and gradually increase to the ideal speed. Be sure to use special machine polish. Hand polishing can heat up considerably on the rotary discs and damage the paintwork. To make the polishing machine run more smoothly, the plates can be sprayed with water beforehand. A complete guide to polishing the car, we have put together here.
Purchase criteria for the polishing machine
• Weight of the polishing machine: After all, it is being held in the hand all the time. It should therefore preferably weigh less than 3.5 kilos.
• The size of the polishing pads: the larger they are, the more difficult it is to polish rounded parts.
• Variable speed: The speed should be adjustable, preferably infinitely variable.
• The power of the polishing machine: A rotary machine should have an output of at least 1200 watts, with an eccentric machine we recommend machines with 200 watts or more.
• The length of the cable: The cable should be five to six meters long. With extension cables, there is a risk that the connector plug will “scrape” along the bodywork. Even better: a polishing machine with a battery.