Welders

How many of you have the Eastwood Mig 175 welder? Mine is acting up and I was wondering if someone else has had the same issue. The wire spool that goes on the shaft inside the machine is tightening up against the wing nut preventing the spool from turning. I can't figure out why this is happening. The spool gets so tight against wing nut that it is hard to remove the wing nut.