I bought a Plasma CAM 4 mounth ago and it worked just fine cutting sheet metall, but for some time I tried to cut some square pipes 40x40x2mm (make a longitudinal opening of 13mm width on one side), and some things are not right. For example I figured to fix the machine (to compensate the trajectory so it cuts streight that opening), and without doing any change to it, the next day I got differences of 0.5 to 1 mm in the opening position. Also there are big differences between two consecutive pipes (around 0.3 to 0.5mm).
Is this normal for the machine? Does anyone know what the accuracy of this machine realy should be?
Thank you in advance,