How to MIG Weld Repair some Crapped up Holes

This is a Crappy Weld Repair

What’s crappy about it?

That’s real CRAP you see in this video of a mig weld repair.

This is a remote controlled camera tractor that inspects sewers…meaning this thing has been in real CRAP.

Smells like a dozen roses when you weld it too.

Not all welding jobs are pretty shiny new metal. But if you have been around a while scratching out a living taking on odd welding jobs, you know that already.

I have fabricated a whole bunch of these from new metal and that’s gravy work. There is some mig welding and there is some tig welding required. There are stainless axles and pins welded to A36 Steel. I use ER309 for the dissimilar metal welds ER70S2 for the mild steel tig welds and ER70S6 bare wire for the mig welds...and it is gravy man...

But when these things break,(they get beat up pretty bad in service) , it’s a crappy job.

This weld repair is to fix some damaged threads. The threaded holes that got messed up were pretty small holes so in order to be able to completely replace the damaged metal, the holes were hogged out with on a mill.

The machine shop took care of that part.

But that is not always the case. Often times, I have used a grinder before to groove out the hole prior to welding...no big deal. but you have to open up a threaded hole enough or you just wont be able to get good fusion in all the walls.

I probably should have cleaned around the hole a bit better but that has not given be any problems in the past so I just fired up on it.

Using .035” ER70S6 bare wire with 75/25 argon/Co2 gas around 19-20 volts and about 200-250 ipm of wire speed, I welded all the holes up in just a few minutes.

Swapping from hole to hole helped to keep the heat down so that I could accurately place the final contour beads so that the part would clean up on the mill to original dimensions.

I wrote a page years ago about starting your own welding business

and one tip I gave for getting started with your own sideline business was to approach local mom and pop machine shops for work. This is a perfect example of the type of work that a good welder can get from small machine shops.

Machine shops make mistakes too. And when they do, sometimes a good welder can bail them out.

Miscut corners, misdrilled holes, taps broken off in holes, and also assembly of machined parts are common welding jobs that machine shops need done.

Big machine shops are likely to have decent welders on staff.

But the mom and pop or one man machine shops don’t always have the welding skills needed to fix mess ups or to weld on expensive machined parts that require welding for assembly.

So if you are trying to get started in your own welding business, that tip is still a good one.

Just be willing to take the crappy jobs along with the gravy jobs. exit weld repair page and see mig welding techniques