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Re: MIG for Cast Iron + Small Welding Table
Posted: Thu Sep 27, 2018 4:17 pm
by Harold_V
steamin10 wrote: ↑Thu Sep 27, 2018 4:17 am
7018 was annoying in that it did not like anything but clean metal and would give you fits with old rod.
I'm likely going to say something stupid here, as my memory isn't great, but 7018 is critical of its environment. It should be stored in a hot box once opened, and used within a few hours (something like four of them) after being removed. Simply placing such rod back in a hot box isn't enough if the welds are certified. It's a wonderful rod, but it has stringent requirements. It is referenced as a low hydrogen rod, thus is must be moisture free, unlike some of the other rods.
7018 was the basic rod we used in the welding class I pursued. My purpose was to learn to weld a boiler. I learned the necessary techniques, but there is NO substitute for experience, and one gets that by welding. And welding. And welding, ad nauseam. That's the part I still need in order for me to proclaim myself a weldor.
H
Re: MIG for Cast Iron + Small Welding Table
Posted: Thu Sep 27, 2018 5:17 pm
by Russ Hanscom
The other thing that gives welding fits is wind, if you looking for a quality weld. When we were welding in Moab, single digit humidity, 4+ hours out of the box or a slight breeze would show up on the xrays. That is the second use for welding shelters, keeping the weld zone wind free.
Revisiting a previous point, when welding mild steel, there is no advantage to using a 70 series rod over a 60 series rod, either significantly exceeds the strength of the parent metal and the failure will either be in the parent metal or HAZ (heat effected zone) unless the weld is really bad.
Re: MIG for Cast Iron + Small Welding Table
Posted: Sun Sep 30, 2018 4:34 pm
by GlennW
Well, I ran into the dude today that I did the weld repair for and it's doing fine.
It was a casting for a machine in a commercial wood working shop. Since the machine was down for a couple of weeks work was backed up and they have been running the tar out of it since it was repaired.
Encouraging...
Re: MIG for Cast Iron + Small Welding Table
Posted: Sun Sep 30, 2018 5:51 pm
by liveaboard
I welded up a cast iron exhaust manifold once; cut it to pieces, sectioned it so it would point in another direction.
I bolted the parts to the head, tacked it together, removed it, welded it up, and then had the ports machined flat, because after welding they looked like a bunch of bananas.
Came out ok. Used stick, some cast iron specific ones, no idea what they were called.