Hi Wizcrafts, sorry if I answer only now but I haven't been home. thanks to you, I managed to solve the problem. The first problem is that the height of the central foot was not well adjusted. the second problem was that I only understood later. is that the tip of the needle was in the right adjustment position when it came up and not when it came down. in that case I aligned my feet and solved it. I just have to adjust the pressure or maybe even the height. still marks leather a lot. thank you very much for the help!