Please advise on welding threaded bung

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As shown below, I need to weld the bung into the tubing. Two questions:1) should I insert a bolt into the bung before welding to protect the integrity of the threads, or will the bolt get fused in?2) do I set the amps/wire speed for the thickness of the tube or a little higher to compensate for the bung thickness?Lee TiltonSCCA F500 Pilot
Reply:1) No and no. 2) Bung and weld the bung TO the tube.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:Uhhh what?Miller Thunderbolt 225Millermatic 130 XPLincoln HD 100 Forney C-5bt Arc welderPlasma Cutter Gianteach Cut40ACent Machinery Bandsaw Cent Machinery 16Speed Drill PressChicago Electric 130amp tig/90 ArcHobart 190 Mig spoolgun ready
Reply:I do not think that the bolt will get fused. especially since your material looks to be aluminum.I know that with pipe fittings you dont want the fittings tight before welding, or else you will never get it back out. Probably not as bad with a bolt. Try to cover the hole with something that doesn't thread in.
Reply:I often do smaller parts out of SS, and I have found that distortion is a big problem with the threads. Coat the male threads on a bolt with anti-seize, and install it into the bung. Immediately after you weld the bung on, get a wrench, and gently turn the bolt in the threads for a few seconds. It will keep the threads trued much better than just winging it.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:If, as indicated by his post, that's a suspension piece for his F500, I doubt highly it's aluminum.Lee, it looks like you've got a threaded spud slipped through the tube that your heim joint threads into.  You shouldn't have to worry about distortion on the threads considering the difference in section thickness.  I do these all the time  (Okay, maybe not all the time, just when some other racer doesn't leave me adequate racing room)  Just don't leave the heim in there while you're welding KB - Spec Racer Ford pilotI r 2 a perfessional
Reply:Originally Posted by RojodiabloI often do smaller parts out of SS, and I have found that distortion is a big problem with the threads. Coat the male threads on a bolt with anti-seize, and install it into the bung. Immediately after you weld the bung on, get a wrench, and gently turn the bolt in the threads for a few seconds. It will keep the threads trued much better than just winging it.
Reply:Originally Posted by sn0border88I've done hundreds of SS weld couplings from 1/8 to 1 1/4 and never had one come back because of distortion.Also welded lots of SS nuts and never had a problem.Are you talking about SAE thread or tapered NPT threads?