Have you considered a spooled gun? Is the twisting causing feeling problems? Feedability is probably the most common problem experienced when comparing MIG welding of steel to MIG welding of aluminum. Feedability is by far a more significant issue with aluminum than steel. This is primarily due to the difference between the materials' mechanical properties. Steel welding wire is rigged, can be fed more easily over a farther distance and can withstand far more mechanical abuse when compared to aluminum. Aluminum is softer, more susceptible to being deformed or shaved during the feeding operation, and, consequently, requires far more attention when selecting and setting up a feeding system for MIG welding. Feedability problems often express themselves in the forms of irregular wire feed, excessive bending in the electrode transport tube, excessive bending in the guide tube of the gun, excessive bending of the cable between the drive unit and the welding gun, or the fusion of the welding wire to the inside of the contact tip, which is caused by kinks jamming in the gun. If the kinks feed through, they will produce a momentary slowing of the electrode. Improperly wound spools with crossovers or edge bound strands will also cause erratic feeding. The aluminum electrode can also sieze and gall inside the contact tube, causing an erratic or stitching arc action. In order to prevent excessive problems with feedability of this nature, it is important to understand the entire feeding system and its effect on aluminum welding wire. When starting with the spool end of the feeding system, the brake settings must be considered first. Brake setting tension is required to be backed off to a minimum. Only sufficient brake pressure, to prevent the spool from free wheeling when stopping welding is required. Electronic braking systems and electronic and mechanical combinations have been developed to provide more sensitivity within the braking system. Inlet and outlet guides, as well as liners, which are typically made from metallic material for steel welding, must be made from a non-metallic material such as nylon to prevent abrasion and shaving of the aluminum wire. Even so, there still can be feeding problems. Drive rolls have been developed, often with U type contours with edges that are chamfered and not sharp, that are smooth, aligned, and provide correct drive roll pressure. The electrode may slip in the drive rolls because of insufficient pressure. Excessive drive roll pressure can deform the aluminum wire and increase friction drag through the liner and contact tip. Contact tip I.D. and quality are of great importance. There are contact tips made specifically for aluminum welding, with smooth internal bores and the absence of sharp burrs on the inlet and outlet ends of the tips which can easily shave the softer aluminum alloys. Aluminum welding wire is used in both push and pull feeder systems, however, limitations are recognized dependent on application and feeding distance.