Welding thick metal

[JasonW]

So I’ve finally saved up and bought a pole barn but needed something to help lift posts and trusses. I had bought a scissor lift to help with it but recently got a KX040.

Yesterday ended up finding a homemade/well built boom jib from a KX057. Which has a different quick coupler than my KX040.

So long story short I have to cut the mounting ears off the boom and weld on new ears sized for the KX040.

What would be the best way to weld 1/2” to 3/4” plate? I have experience welding but nothing this thick. I have a Miller 215 and a Miller Thunderbolt XL, and Lincoln square wave 205. So I should be covered on machines.

 

[#40Fan]

Bevel and pre-heat. Lay it on thick with many passes.

 

[JasonW]

Bevel and pre-heat. Lay it on thick with many passes.

Any preference to process? All mig? All stick? Root pass with stick and finish with mig?

 

[EPIC]

Stick or MiG will work…. Assuming you are not welding in a windy area. High winds can blow the shielding gas away.

Concur with bevel and pre-heat.

But don’t forget that weld heat can and will pull material out of square, so make sure you have it braced well before you start!

I would use MiG assuming the wind issue can be solved.

 

[North Idaho Wolfman]

I just use mig.

 

[Tarmy]

As noted…bevel, clean area, heat…lots of heat(amps), and get a good root pass in to layer on top of…watch distortion or movement on early passes.

 

[hagrid]

7018 in 5/32 diameter.

 

[John T]

propane weed burner works great for preheating
I used one for a long time before I discovered the turbo torch

 

[whatsupdoc]

Use what ever method you are better at mig or stick. When I welded for a living (only for a short time)
I would do a root pass with 6010 then fill with 7018

 

[jaxs]

Use what ever method you are better at mig or stick. When I welded for a living (only for a short time)
I would do a root pass with 6010 then fill with 7018

That's what lots of pipe welds spec so it must be good.

 

[JasonW]

I would say I’m better at MIG as I haven’t stick welding anything in probably a decade. I have torches so I’m covered on the preheating.

 

[GeoHorn]

Thick metal isn’t my challenge. THIN stuff is MY problem.

Today, I needed some 12’ Cee-Purlins to be 12-ft long…and all that was available were 10-footers… So I cut one up into 2’ lengths and welded them onto the ends of the 10-footers….

A chop-saw isn’t very exacting when cutting purlins and to butt them together required jumping a 1/8” gap in much of the mating surfaces.…and they are only 16-ga metal…. so it’s easy to “blow” holes all over the place.

It was do-able…but it’s not presentable without “gobbing” it in some places and then grinding it flat again. (Rustoleum rattle-can paint helps appearance.)

(I wonder if a heavy sheet of copper beneath it might help provide support for the bead to “settle” or “puddle” into place..?)

 

[sdodder]

I just use mig.

My vote would be for stick. I'm old, and have LOTS of stick welding experience. When I first started welding, MIG was a new thing!
I do use MIG, but mostly for lighter stuff - I myself prefer stick welding for HD welding.
Good luck- Steve

 

[Ping]

Thick metal isn’t my challenge. THIN stuff is MY problem.

(I wonder if a heavy sheet of copper beneath it might help provide support for the bead to “settle” or “puddle” into place..?)

Yes, for your 16ga stuff, a copper plate/bar or ceramic root backer will help considerably when bridging gaps.

 

[snoeproe]

If it’s all fillet welds, it would be 7018 stick for me. 1/8”-5/32” size. No reason to use anything else. You have a DC stick welder?

 

[ferguson]

So I’ve finally saved up and bought a pole barn but needed something to help lift posts and trusses. I had bought a scissor lift to help with it but recently got a KX040.

Yesterday ended up finding a homemade/well built boom jib from a KX057. Which has a different quick coupler than my KX040.

So long story short I have to cut the mounting ears off the boom and weld on new ears sized for the KX040.

What would be the best way to weld 1/2” to 3/4” plate? I have experience welding but nothing this thick. I have a Miller 215 and a Miller Thunderbolt XL, and Lincoln square wave 205. So I should be covered on machines.

1/2" & above thickness set up with a open root 1/8" / root pass then grind out the other side / add a root pass on that side / Stick or mig witch ever your better at.

 

[JasonW]

Well the new mounts came in yesterday. Got the old larger mounts cut off and surface prepped. Next step is bevel the new mounts and weld them on.

 

[Runs With Scissors]

Well the new mounts came in yesterday. Got the old larger mounts cut off and surface prepped. Next step is bevel the new mounts and weld them on.

The Rule is….”Pics, or it didn’t happen” my brother

Just sayin….

 

[JasonW]

Well here is a before picture. I’m terrible at taking pictures throughout a project.