hermetic
Member
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- 469
Right Chaps, I have been trying to tig two peices of approx 2mm x 60mm dia aluminium pipe together at 45 degrees. Cut them on power saw, cleaned with stainless brush, degreased with thinners, assembled together in vice, perfect fit, virtually no gap, and off we go. Now I should say at this point that I am using a transformer machine, no foot pedal, and I am very inexperienced with alu, but I have done a couple of jobs that turned out ok, not pretty but definitely welded! No 7 gas cap, 2.4 gold tip tungsten with a little ball, AC, tried various different current settings, and the result is that the metal melts and spatters at both sides of the joint, but shows a remarkable reluctance to fuse across the join, even when I add filler rod into the gap, the arc seems to sputter and blow the filler rod away and I end up with blobs of matt grey metal with lots of porosity on either side of the join and no weld. also lots of black soot around the weld area. I accept at this point that I am a total "see you next tuesday" and having not at first succeded, I give up, get out a lump of 3mm aluminium sheet, and practice running some beads along it, there is an immediate difference, I can see the weld puddle clearly, add filler metal to the edge of the puddle, and almost produce a respectable bead! The material I am trying to weld is the centre tube from a gas boiler flue, it is unused, very clean, and appears to be extruded, Is it the material, or is it me? any suggestions greatfully recieved.
Phil
https://www.youtube.com/channel/UCKf0nWnXKXltBjj7MWtdjWA
Phil
https://www.youtube.com/channel/UCKf0nWnXKXltBjj7MWtdjWA