On a recent weld job, my MIG welder ran out of spool wire. I replaced the empty spool but it failed to feed out of the MIG weld torch handle due to some soet of internal blockage.
So my weld job was halted and I moved onto repairing the welder itself, great!
Step 1: The Problem
The spool wire seemed to be obstructed somewhere near or in the handle.
The main welding conduit hose carries
+ a heavy current wire
+ a spool wire conduit
+ 2 wires for the trigger switch.
It seems the plastic spool wire conduit was slightly bent causing the spool wire to snag internally and prevent it from feeding onwards. Most likely caused by frequent bending of the handle, and the sharp cut mig wire snagging in the bend.
Step 2: The Solution
So I needed a replacement conduit for the spool wire. At first i thought of replacing it with a long rear bicycle brake cable (outer bowden part).
However, most bicycle brake cables have a plastic inner sheath which acts as a lubricant for the brake wire. This was not ideal as feeding a new spool wire could again snag internally on this.
So my next idea was to use the spiral sprung type of net wire used for curtain linens. This appeared to be ideal, as it was also much more flexible.
The dimensions also matched the existing plastic conduit. I use 0.9mm diameter mig wire and this passd through with slack.
Step 3: The Fix
The spiral sprung net wire was cut to length using a dremel cutting disc. You could achieve the same result using a pair of wire cutters and a file.
The spool conduit was fed through the main outer hose replacing the plastic spool wire conduit.
The handle came apart easily by removing the screws. The brass feeder ferule was screwed out from the brass block near the trigger switch and then re-attached.
A new cable tie was attached as an outer hose self restrain within the torch handle.
At the other end, the spool wire conduit was simply clamped into the motorised wire tension feeder.
Step 4: The End Result
The new spool wire fed easily through the new conduit. The handle was also much more agile and flexible, what a bonus!
Overall very happy with this simple, low cost, robust and effective repair.
Now back onto the weld job itself!
Hope this helps others.