[StutzJr]

Great thread, very informative stuff. I'm also interested in doing a tafe welding course eventually.

I have a specific question relating to the welding of fine gauge wire thermocouple junctions. I'd like to know the best option(s) for welding precision grade thermocouple wires ~24 AWG (0.5 mm diameter or less). The idea is to twist a short length at the end of two wires of dissimilar metals and then fuse them together into a small bead. Soldering is not an option due to the introduction of contaminants and the intended temperature range of the t/c. Similarly with silver soldering.
I have found that a butane torch is not hot enough and/or is not able to fuse the wires without oxidation. I have tried capacitor discharge (resistance welding) with carbon terminals but do not have a large enough capacitor to get an effective weld. A workmate has a MAPP gas burner but I expect it will only be a marginal improvement over the butane torch.
I've been advised by a local supplier to try a neutral flame on an oxy welder. I don't have access to any oxy-acetylene gear but I am considering investing in an oxy/MAPP welding kit. I've also been eyeing the aformentioned bunnings special arc welders.. Lastly I have been hearing a lot recently about jewellers using HHO welders (hydrogen-oxy derived from water) but I believe that these units are pretty rare and expensive around here.
Can anyone here suggest what technique/equipment would be the best option for my application?