Ground Clamp cable Length

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I found myself in an awkward situation MIG welding aluminum this weekend.  Using an Lincoln Weld-Pak 155, I've found if I don't keep the torch hose as straight as possible, I'll have wire feed problems.   (I've gotten into the habit of zip tying the torch hose to a length of 1/2" PVC water tubing to keep the hose straight.)  The nature of what I was working on, caused the work to be positioned such that I couldn't attach the ground clamp and still keep the torch hose straight.  For some unknown reason, the cable on the ground clamp is about 24" shorter than the torch cable.  I got around the problem by using one lead of a car jumper cable and it seemed to weld fine.   My question is, is there any reason I shouldn't open up the MIG unit and replace the ground clamp cable with a longer one, say 2' longer than the torch hose?There are no small projects
Reply:Yeah, this is common problem with mig especially the smaller units.  Also, if you have used it much replace/clean the liner and keep tip clean/replaced.  They sell cleaners (felt brushes) for your wire. They clean the wire as it is fed into line.  This will help the alleviate feed problem, also.   Try to eliminate as much friction a possible.  I also used tips one size larger than wire without problem. I don't know how large the 155 is, I put my 65 lb welder on a cart that was 5' tall. It helped with cable routing when working on a bench.   Got the idea from the seeing wirefeeder hung. Don't see any problem with adding to ground as long is proper guage wire is used.
Reply:the big problem with MIG welding aluminum is that aluminum is a very soft metal and bends easily, therefore causing it to bend and bind up in the hose. The typical response to this problem is to use a spool gun. It's the same function as a MIG welder, but instead of the roll of wire being at the machine, it is in the gun.
Reply:Using a teflon liner rather than a regular metal liner will help, along with a shortened gun hose (I use an 8' one but have seen even shorter)...What you are doing with the pvc pipe sounds like a good idea also.  You want it to feed as strait as possible.  I am not sure if oversizing the liner and tips helps.  I tried that a few times and didnt see any real difference, but that might be just me.  One thing you do want to do is to use smooth-groove rollers and use the lightest tension on the wire that you can get by with.  Gnurled rollers chip and deform the wire and this causes two things, 1) aluminum crud in the liner, and 2) weaker wire.  Both make feeding more difficult.  Thicker wire feeds better, but I am not sure how thick you can go with that welder...probably not too thick...maybe .035 max for a 155? amp machine (I am assuming this is a 155 amp machine).like brad said, a spool gun is the method of choice, either that or a push-pull system, but both of those are quite a bit more expensive than the average feeder.Smithboy...if it ain't broke, you ain't tryin'.
Reply:Thanks for the input.   Shortening the torch hose is a possibility, but at the very end of my list.   I actually have a used gun taken off a Millermatic that has a wire puller built in, I just haven't taken the time to figure out how to tie it into the controller for the small Lincoln I'm using.   I do use a teflon liner and I've drilled out the electrode tip to 3/64" (I'm using .035", 4043 wire).    I was advised that 5356 will feed better, but will eventually cut through the teflon liner.There are no small projects