Interesting, thanks. I have a 240V MIG with reversible polarity. But no bottles for gas and as such haven't even attempted aluminum yet.I did mig welding on aluminum for some time back in the 1980s. A 120V welder is useless for that. The polarity is reversed, as others have pointed out, and I also had much better welding when I used a helium/argon mix. I ended up using two bottles (one argon, the other helium) and two flowmeters, teed to the welder's gas line, and adjusted the flows to what worked the best for the castings we were welding. Helium brings the heat up a lot and you can use less amperage.
Teflon liner, rubber roller so that the aluminum doesn't get deformed by the rollers. No preheating at all.
We also welded a lot of cast iron using nickel wire. Lots more hassle than aluminum. The best aluminum guys are those that have never welded steel. No habits to unlearn. Aluminum has a very narrow plastic state temperature band and steel welders can get frustrated by its sudden melting away into a puddle.
Oxyacetylene welding aluminum is a futile pursuit.
You need to preheat that part almost melting point to weld it that low amps. 120 amps don´t have enough penetration to weld it like it should weld....we are talking airworthy parts here.You certainly need good welds for this but it's not impossible to do that with a small welder. My Mig is only 120A and I have easily welded billets weighing around 5kg/12lb. You definitely need to do test pieces and if you're not able to sustain a good puddle then increase the preheat temperature until you can.
As you like... I have done it, regularly, as a matter of course. It does require some understanding of the variables. Fine wire is a must. An exceptionally high wire feedrate is another. I wasn't saying it is easy but its not that difficult either. Not so many years ago I employed 4 full-time aly welders in my shop so I have a rough idea of what I'm talking about, with respect.You need to preheat that part almost melting point to weld it that low amps. 120 amps don´t have enough penetration to weld it like it should weld....we are talking airworthy parts here.
A 200 amp machine should do the job fairly easily - with sufficient preheat - but I'm a bit concerned about this Eastwood one. I have a modern 200 amp inverter TIG which is much smaller than the old induction (transformer) variety but mine is way bigger than this Eastwood one. I know they do ever more clever things with electronics and this Eastwood one has a low duty cycle but even so... some manufacturers are not always entirely honest about the performance of their products - a bit like plane manufacturers you know?Well, I've gone and tried all of these suggestions and no success... I got out the old Oxy-Acetylene torch and was able to weld a couple of pieces together... but it's far too unwieldy in my hands. I always blow through the tube walls...
So now I've been looking at TIG welders. I found one that fits my budget. It's AC or DC (switchable), has the foot pedal control, "high-frequency start", and can output a maximum of 200 Amps. Does this thing look like it would do the job? I'd love to have a TIG welder anyway, but it needs to be able to weld those heads.
The welder: TIG Welder - Eastwood AC/DC TIG Welder | TIG Welding | TIG Welders
The question though is "Can it be made to work in such a way that a rational and sane person would be willing to bet their life upon it?".A plain buzz box welder attached to a TIG torch can be made to work for welding aluminum. By no means ideal but do able.
Just like in the US!most chinese stuff here is way cheaper than US goods.
It's an intake port on each head... The mechanical stress is about as minimal as it gets. I'd use JB weld if I thought it would take the heat and vibration. onder:If your life depends on it and you don't like the idea idea of experimenting take the advice of others and have it done by a certified welder.
I don't mind learning to do it myself because I don't think it needs to be quite the level of a weld coming out of the Electric Boat Company. The question was is that particular technique able to be made "to work" sufficient that it's comparable to other techniques in the hands of someone with comparable skills in each.If your life depends on it and you don't like the idea idea of experimenting take the advice of others and have it done by a certified welder