Archive for April, 2015

Christmas Present 2014

Wednesday, April 15th, 2015

My present to myself this last Christmas was a PowerCRAFT TIG 200 AC/DC welder. It’s made by Lincoln Electric, one of the big US welder manufacturers. They are clearly competing against the widely available cheap Chinese welders and, whilst it is using their technology, it is manufactured in China. It can weld steel and stainless steel, as well as aluminium, magnesium, titanium and zinc, probably more.


It has a one year warranty rather than their usual two, is housed in an off the shelf box rather than their signature style, and the duty cycle is less than, say, there Invertec semi-pro range. It appears to be their last generation in terms of functions, so is ahead of the Chinese stuff with flexible pulsed DC and mix AC, but not the current ‘best-of-show’ potted circuit boards to avoid steel grindings or spatter causing damage, square wave AC and automatic higher current at the start of a weld to heat the surrounding metal which then reduces after a preset time, but these are incremental improvements, not game-changing ones.
I have dabbled with my neighbour’s TIG welders over the years. Welding is a large part of his business, so he has 6 TIG welders (including just buying one of these ones), of varying vintages and capabilities, a couple of MIG welders and an oxy-propane set (acetylene is out of fashion these days) – oh and a plasma cutter. Some are the older transformer type which are 3-phase and weigh 100 to 200 kg, to the latest inverter types with all the bells and whistles only weigh one tenth of that.
I am now getting my eye and hand in more. It is a precison welding process, so combining keeping the arc length reasonably constant and speed fairly quick is important for good results. Since the arc length should only be a couple of mm, it is necessary to have a hand support, even if it is only a pinkie touching the workpiece to judge the distance. If the tip of the tungsten toushes the weld pool it will be contaminated and will destroy the tip shape and arc and need a regrind. Or, it  short-circuits and the tip welds to the workpiece, again needing regrinding. The same is true for the other hand with the filler rod. If the filler rod touches the tungsten it contaminates it and it will need to be reground to a point.
Having now finished the bike lift/work bench, I have also welded up a smoke generator for cold (or hot) smoking food – another wee side project I’m toying with, more to follow. I got a ‘free’ 24″ TV with a Panasonic Lumix camera body/lens kit and I cut up the stainless steel for a wall mount today. Tomorrow I will drill the required holes, weld it up and mount it in the shed. It is LED, but not a SmartTV, so I have bought a Chromecast for it and will let you know how that goes.