13 years ago
I got myself roped into a project making up frames for panels to
protect stained glass windows when a church sanctuary is used for a
gym during the school week. We went and got $800 worth of 6063
rectangular extrusion from the metal yard, and I'm having an
incredibly tough time TIG welding this stuff.
I don't have a lot of material to spare while fooling around,
either, we bought them out of an odd size, 1 x 1 7/8 x 1/8" wall.
(That's 1 x 1.875" outside dimension.)
I just got in some 3/32 Zirconiated tungstens, a gas lens set for that
size, and some 3/64" 5356 MIG wire for filler. I got a pretty good
fit-up of the edges after a whole bunch of fooling around with my 4x6
hor-vert bandsaw. I tried to weld this with without grinding a vee to
fill, maybe that is part of the problem, although my TIG book suggests
that is possible up to 1/8". I have a Lincoln Square-Wave TIG 300 that
as far as I know is working perfectly. I have a Weld-Craft
water-cooled torch with a Miller cooler. I know that MIG wire is
not the perfect thing for TIG, but I'm not even sure I need filler wire.
Does anyone have any advice on what to do, common newbie pitfalls,
etc? Obviously I can't support the back of the weld inside the tube. I
think preheat is going to be needed, I have a Bernzomatic propane torch
and an Oxy-Propylene set (essentially generic Oxy-MAPP) but have no
idea how much pre-heat to use. I did try welding a couple pieces
of tiny scrap, and that went a LITTLE better, I did actually get fusion
along part of the seam. That sort of supports the idea it needs
preheat. I KNOW I'm in way over my head, here.