I have 2 pieces of aluminum that make up a kind of finger hinge. The two sections are each 3/4" wide pipe each ending in finger joints with a hole drilled through the fingers. A cotter pin has been used as the hinge pin during the mock up, but now a permanent hinge pin is required and due to space regulations it must be very flush and end on either side with a flat round, similar to a nails head (striking surface). I was going to merely insert a nail, then put a tightly fitting washer over the other end, and briefly mig weld the end of the nail protruding through the washer too the washer. The opposite end will have a small thin piece of cardboard as a temporary spacer to ensure a snug but not too tight of fit. Of course the rest of the aluminum will be shielded from weld spatter. The weld would then be ground flush. There will not be a lot of tension put on this weld, but some minor vibration. There will 5 of these pipe section with 3 joints per section each, they will be very close together and require the ability to move independently from each other, so no shared pins.
Will a very brief weld cause the pin/nail to heat up to a point that it causes the surrounding aluminum to melt and "horribly" cause the 2 joints to fuse?
The 3/4 span is much to wide for a pop rivet and would have to much of a bump on the sides.
Bolt and nut would also have to much of a bump, and introduces the destructive effects of a steel thread running through an aluminum body.
Philadelphia screws are just too wide for this application
Actually peening a real rivet will put to much stress on the aluminum pieces.
No I do not have the means to weld aluminum, as this is a solder core wire feed welder, not a true mig.
Any suggestions? I have done similar welds before, but all pieces were steel, not mixed.
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