How to Weld Vertical MIG

Scroll down a bit for the best videos on how to weld vertical MIG

The video below shows a proven technique for how to mig weld vertical mig uphill.

There are several different techniques that work for welding vertical uphill with short circuit mig.

The video below shows one proven technique.

HERE are a few key points to remember when MIG welding vertical uphill:

Voltage and Wire speed settings

The recommended settings on your MIG chart are intended for fillet welds on the bench and are almost always too hot for vertical uphill MIG.

The easy fix for this is to simple select voltage and wire speed settings for one or 2 lower thickness metal. ( it also helps to reduce wire speed by 10%)

Short stickout

Once your settings are right, make sure to maintain a short stickout.

Stickout is the amount of unmelted wire sticking out past the contact tip to the arc. A good stickout for short circuit mig welding is 1/2" or less.

Sometimes a mig nozzle and contact tip does not allow for this because the contact tip might be recessed back in the nozzle by 1/2" or so.

If this is the case, I suggest either buying a different nozzle or trimming your nozzle so that your contact tip is flush or even slightly protruding past the end of your nozzle. Stickout is very important for short arc mig.

Gun Angle

Gun angle is also a key factor for mig welding. The tendency is usually too much push angle when welding vertical uphill so Aim for 90% straight in and you will likely have s slight push angle.

Technique for MIG welding vertical uphill

In the video above, you will see a technique that moves the arc along the leading edge of the puddle.

The arc is the hottest area of the puddle and is the thing that does real work... so whatever technique you use, make sure that it plays the arc on the leading edge of the puddle.

I like to call it "tracing the leading edge of the puddle".

Clean the mill scale

The Best techniques and settings won't get you the best results possible if you neglect the cleaning step.

Hot Rolled steel plate has a mill scale coating that can inhibit penetration and invite undercut.

For best results, remove the mill scale with a grinder.

Some metal shapes like square tubing have a very thin mill scale and can be mig welded without removing the mill scale but for thicker hot rolled steel plate, grinding off mill scale helps a lot with short circuit mig welding.