- Welding Flux Core -
For my first time welding I opted to try flux core welding as I didnt need to buy or rent a cylinder for shielding gas. Welding for the first time was daunting enough, so I didnt want the extra complication of dealing with gas bottles for the first time as well. Plus, my welder the Hobart Handler 140 comes ready to weld flux core as it comes with a spool of flux core wire with the machine. With the enormous amount of shit you already have to buy, not having to buy another to get started welding is a huge load off.
What is Flux Core?
Instead of using gas that comes out of a bottle flux core wire uses a flux thats in the middle of the wire to shield your molten metal from the air.
Machine Setup for Flux Core
You must change the polarity of your welder to electrode negative(dcen) for flux cored wire. Make sure the wire that is going into the power block is the wire connected to the negative terminal.
Safety Precautions for Flux Core
Extra bright, so increase the shade setting of your helmet. I use 11.
Produces a lot of smoke so make sure you have proper ventilation or ideally a fume extractor of some sort. I run a household fan over my work area, have an overhead air filter going and keep my garage door open.
Also, due to the smoke, your helmet is going to get more easily clouded, so you must clean it more often to be able to see your welds clearly.
Stickout for Flux Core
Longer stick out than mig welding. About 1/2″ or a little less is good.
Technique for Flux Core
Drag Your Weld
Welding with flux cored wire produces slag so you have to drag your weld. You must clean your tacks also, due to slag.
Stickout
In most cases keep about 1/2″ between contact tip and work piece.
Gun Angle
Your drag angle should be 10-15 degrees.
Movement Across Workpiece
Move at consistent speed, judge by the weld puddle:
too fast = puddle too narrow
too slow = puddle too wide
Misc Notes
Starting welds with flux core is more difficult, it doesnt flow as easily as mig wire because of the flux material. So when beginning your weld, get it flowing and build it up before moving along.
Pushing welds with flux core wire could push slag into your welds.
Clean Slag
Welding with flux cored wire produces slag so you have to chip off that slag with a chipping hammer, then further clean it with a wire brush. Alternatively, you could use an angle grinder with a wire wheel attachment to do both at once.
Welding Guide
Welding Gear
DIY
