Ultrasonic Cutting Knife with 5-Blade Set & Adjustable Speed - Ultrasonic Cutter for Solder Scraping, 3D Print Repair, Plastic/Resin Modeling，22V~

Very disappointed. The instructions that arrived with this unit showed expected cutting speeds for different materials, including a claim that it can cut 2mm thick PVC at 15mm/s. The unit arrived with some small sample sheets, including 1mm thick PVC. I was only able to cut this at 5mm/s at the most. So I decided to measure the input power of the machine. The machine requires a 220V step-up transformer to power the unit from 110V, so I installed a power meter between the transformer and the 110V outlet. When the unit was turned on but not powering the cutter, it was drawing 15 watts. This is reasonable, especially since the 110-220V transformer draws a small amount of magnetization current any time it is energized. Then the cutter was powered on at the highest setting (3 on the dial), the maximum power drawn by the unit + transformer was 31 watts (the power increases a bit when pressing the knife into a material to cut.) Since it's impossible to get more power output than is input to the device, this indicates that the power to the piezo transducer was less than 16 watts. But note that the description says this is a 100-watt unit. This was with a brand-new blade that I double-checked was installed properly and tightly. I also checked that the horn was solidly and cleanly screwed on to the piezo transducer. The handpiece that arrived with the unit did not have any sort of way to attach a cooling air hose, even though this is shown in one of the pictures in the Amazon product page and in the instructions. There was also a length of air tubing included in the box, and some instant-tube type adapters to connect this tubing to larger size tubing (presumably from the customer's compressor), but there was no way to use this tubing since the handpiece has no way to attach it. "Hello. 1, the question about the power is normal, in actual use there is really only a small amount of power. 2, Regarding the air hose connector the manufacturer gave us a reply that it was originally designed to cool down the handle, and now the problem has been improved, so there is no need to connect the air compressor, no need to connect the air hose." They did not "improve" the problem, they simply reduced the input power to the handpiece (and therefore of course decreased the cutting capacity) Of course the handle isn't going to heat up if it's getting 1/6th of the power!!!! Since there are 30-watt ultrasonic cutters available at 1/3rd the price of this unit, I'm sending this unit back.