Mig Welding

[wouldhee]

Just started using Argon mix (from Hobbyweld) rather than straight Co2.
Results very pleasing on P2 sills*. Far less splatter.
( see 'photobucket' under 'wouldhee' if you are interested in sill progress.... ongoing project ...slow!

[David Bliss]

I have been welding for 50 years, but only started to do mig welding when I needed to do car bodywork, Originally, on our farm, I found that mig welding on heavy steel was inferior to high-amperage stick welding, this was the the cause of many failures on farm machinery. However, needs must, so when I was given an old, small, basic mig welder I began to use it and I soon discovered its limitations. I am an inveterate modifier and soon improved its performance. First of all I found the small gas bottles insufficient for my needs and expensive, so I went to BOC and now use Argoshield light and with a good regulator (BOC or equivulent - cheap regulators seldom work well) this seems to make the work much smoother. I then had problems with the valve on the gun, it tended to stick and leak gasses (only to be expected with a cheap, light duty item). I simply did away with this valve and, as the mig uses a 24 volt supply for the wire feed, I put an air solenoid into the circuit. This allowed me to use a lot less finger pressure to operate the gun so when I was using it for stitching it made it much more controllable, it also stopped further gas leaks and wastage. Over the years I have used other peoples migs from time to time, one of two have been top end high-tech models but these still don't perform as well as mine in certain situations such as confined spaces, also the smaller gun shroud keeps the gas concentrated in a small area preventing spitting and contamination by fumes from pain, rust etc. The smaller the gun the less gas you use, the difference is considerable. The gas shroud round the weld is more concentrated giving better results on car bodywork. If you have ever tried welding in a windy situation you will know the problems that come with the welding gasses being blown away..

A very important point is to see that your mig wire is stored carefully between uses. Any rust on the wire, even if not visible, insulates the wire from the copper tip causing jerky wire feed to the detriment of the weld. I have heard number of people complain about their migs, saying that they weld OK when new and on certain occasions, but not every time, this is almost certainly down to rusty mig wire. If I am not using mine every day I remove the wire and store it in an airtight plastic tub. People have often told me that their wire has been left in for a year or two - these people believe that the coating on the wire will keep it good, but in poor conditions this protection may only last a few days. Always buy your wire from a supplier with an quick turn-around or the wire may have deteriorated even before you buy it.

[Phil - Nottingham]

Quite correct about rusty MIG wire - I remove mine and keep it in the house. The rust will also deposit in the liner so even with new fresh wire problems will ensue till the liner is removed and cleaned or replaced