Arc welding overhead using 7018 rods boils down to 3 main things.
The best advise I can give anyone for welding overheard with 7018 is to
set the machine hot enough so that the rod wont stick when you hold a
tight arc.
....then .....hold a tight arc.
That takes care of most issues.
But there is one more thing that makes a lot of difference.
Rod Angle.
If you use too much rod angle, thats bad.
Too much drag angle will cause the force of the arc to push molten metal to the back of the puddle and mound up and thats bad.
and not enough heat will cause the bead to pile up and slag to drip on your feet.
Arc Welding overhead with 7018 should be done with about the same amperage
it takes to make a weld in the flat position.
Dont fear the amps....but dont get crazy.
Make sure to keep a tight arc.
There is a tendency for welders to turn the heat down for overhead thinking that too much heat will cause the weld to droop.
Well, that could be true if you get carried away and use way too much heat and hold a long arc.
But the combination of the arc force from the right heat, and a tight
arc and good rod angle will drive the weld in and make if fan out flat
if you do it right.
So here are the settings I used for this video.
first pass , I used 3/32" Lincoln Excalibur 7018 rods and about 95 amps.
It seemed ok but I could have used a bit more heat so I turned the amps
to about 100 for the rest of the beads done with 3/32" Excalibur 7018
rods and that worked better. I could hold a very tight arc without sticking the rod.
I used that little Everlast 160sth and it never stuttered.
(Its pretty amazing that a tig/stick welder the size of a lunch box can burn 7018 1/8" rods at 140 amps with no hiccups.)
For the last layer of 3 beads, I switched to a 1/8" 7018 by Techniweld. ( kinda cheap rods but they burn good).
I cranked the heat all the way to 140 amps for the 1/8" rods.
All the while, I tried to keep a tight arc and limit the rod angle.
And...I used that pinky to thumb collapse technique a lot.
--
Jody Collier