Spot Welding Titanium

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Hey everyone.  I am totally new at welding and would appreciate any help you guys can offer me with this.  Basically, I need to weld a nickle wire to .06 in titanium.  I was thinking spot welding.  few questions - is this possible with spot welding?  I see a lot of stuff about spot welding steel but haven't found too much online regrading titanioum.  Also, I looking to buy a spot welder for this job.  I've come to the conclusion that miller and hobart are the two i should look at as i didn't see any resistance welders from lincoln.  What welder would you guys recommend that i get?  There seems to be a few different options from both and i don't know what criteria i should use to decide.  Any help would be appreciated.  Thanks a lot everyone.
Reply:got this from here http://www.key-to-metals.com/Article134.htmcouldnt tell you how good the source is, but its the first thing google foundhope it helpsResistance WeldingTitanium, with an electrical resistance similar to that of stainless steel, is ideal for spot and seam welding. With sheet up to 1.5 mm (0.06 in), sound joints can be obtained with conventional equipment over a wide range of machine settings.Joint quality depends largely on surface preparation. Titanium, normally supplied descaled and pickled, can generally be welded without further treatment, but it is useful to abrade the surfaces lightly to ensure uniform contact resistance.Any scale, tarnish, dirt, oil or grease acquired during handling, storage or fabrication must be removed. Chemical treatments give the lowest contact resistances, but mechanical cleaning gives values almost as low and enables equally good joints to be made. After surface preparation, titanium can be stored for long periods without deterioration of welding characteristics provided that it is kept absolutely clean.Shielding gas is not normally used in resistance welding because of the short welding cycle.Spot welding electrodes should be made of heat-treated copper-chromium alloys. The working face should be domed, as the conventional truncated cone profile may give excessive indentation with titanium. A dome with a 75 mm (3 in) radius can be used for most gauges of sheet.Seam welding. For seam welding, a heat-treated copper-chromium alloy is recommended for the electrode wheel, which should have a 75 mm (3 in) radius face. The welding load should be appreciably higher than for spot welding, because of the longer arc of contact between wheel and sheet. For first trials, a load two or three times that quoted for spot welding is suggested. Welding currents are best determined by practical test.Initially, various welding currents should be tried with equal on-off times or with longer off-time, still keeping the total time close to the value shown. Metallographic tests are recommended to check the degree of overlap between successive spots, and care is necessary to distinguish between the columnar grains of the weld plug and the surrounding heat-affected zone of unfused metal. A high standard of metallographic preparation is required; examination under oblique light at low magnifications (x 10) is usually most informative.Mechanical Engineer
Reply:Welding nickel to titanium will be difficult, if not impossible, with resistance spot welding.  Titanium to nickel forms very brittle intermetallics.You might consider brazing.Regards, KevinI r 2 a perfessional