I always hand file my chains but I have trouble keeping the angles all the same. So, I ordered one of these last week. I set it up the way the instructions and videos showed and sharpened one side of the chain. I switched and sharpened the other side. As, I sharpened the other side, I noticed that the carbide was cutting high on the teeth. So, I went through the setup again and started again. After a few teeth, I noticed that the carbide was cutting high again. I had the thumbscrews as tight as I could get them and it seems like they were sliding, thus throwing off my setup. I went to check my setup again and accidentally dropped the handle and the carbide. It fell about 2 feet on to my gravel driveway and the carbide broke in half. With that I decided to send it back and work on my hand filing technique.