first i new to this site so im gonna say what up.

now for the problem. i have a miller 175 that has a tendacy to just decide to turn the voltage wide open when it wants to at times. usually when im welding something thin like body panels and stuff. when i weld something thicker i cant really tell the difference but it does do it at times. i am wondering if it is the voltage rheostat on the machine thats shorting out. im kinda curious if this is a common problem or if someone else had this same problem. i would say the machine is about 10 years old.