Mig or stick?

[Tractorguy24]

Point trying to make here is that while Cincy is not wrong, a layman can generally assume that higher strength metals will not 'plastically' deform (are more brittle) as much as lower tensile strength metals.

Is this also true for filler metals then? I see no reason why it wouldn't.

Okay I should shut up.

Haha please don't

 

[MinnesotaDaveChalmers]

Do not equate tensile strength with brittleness.

I agree. 7018 has a high tensile strength compared to some other rods, but also produces welds with good ductility.

Here are some comparisons:

 

[Sodo]

I need to reweld the handles on a manual pilot hole post pounder.

These are handles that you hold with your hands?
Either MIG or stick will make no difference.
Any electrode or wire will do.

 

[4570Man]

Are we talking about the handles in a T post driver? If so weld the dang things on with whatever makes you happy. I’d use my mig welder because it’s easier to stop and start and I’m not a good enough welder to weld a pipe in a continuous bead. This is like asking if you should use grade 70 or grade 30 5/16 chain to hang a bird feeder.

 

[TractorGuy]

For the most part welding is not rocket science. With proper preparation and penetration you can weld almost anything with almost any welder. I am not a pro nor have I ever had any training other than reading and being self taught. Have been welding with a little Lincoln SP100 since 1993 and only had one weld that ever broke. That was on a piece of 1"x1/8" flat bar so it was a non critical fail. Mostly use Washington Alloy ER70S-6 in .030".

I have done a little stick and tig at work but not enough to become proficient at either. On a good day I can lay down a good bead with either.

Here is a homemade post pounder I built using black pipe and a hunk of stainless (unknown grade) bar stock for the weight and pounding surface. I screwed together 3/4" black pipe fittings for the handles. I bored recesses in the large pipe to set the nipples in on a mill and ran a bead around the nipples the handles are screwed into. Then I ran a bead around the top to secure the stainless bar stock in the large black pipe. Have pounded a few posts and no signs of fatigue. Weighs in at 28 pounds and will sink a t-post right quick.

Here is the thumb I welded on my backhoe with the SP100 using Washington Alloy ER70S-6 in .030". I can't tell you how many logs, stumps, and trees this thing has picked up and hauled. I have even used it to snatch 8" + trees out of the ground. Had some self proclaimed pro welders say it wouldn't last a day but here it is almost two years later and still as it was the day I installed it.

 

[CincyFlyer]

True enough... different beasts. Brittleness is more of a relative term while tensile strength is absolute. That said, generally in metals the hardness is associated with tensile strength. Higher strength metals tend to have less ductility (bending) before reaching ultimate stress (failure).

Welding is another beast, as locally the metal is upset due to heat and depending also on its cooling, the grain structure can result in a more ductile or brittle structure. Okay I should shut up.

Point trying to make here is that while Cincy is not wrong, a layman can generally assume that higher strength metals will not 'plastically' deform (are more brittle) as much as lower tensile strength metals.

Way deeper than the subject of stick vs. Mig. Oh and I love Mig.

Actually, all steels are about the same stiffness, some are stronger (can be deformed more and return to shape, that is, more elastic before plastic deformation, the opposite of what you've said), and some are harder (now you can get brittleness.)

 

[Texasmark]

Getting to use my HF 151 240V MIG with gas more every day. Seldom use the old Miller ACDC 240V 200A stick. I haven't had any problems welding the thicker steels with it....just build up red puddles and keep feeding material to the joint till sufficiently filled. Thicker material just takes longer, using more wire, but that slowing allows the immediate area to get red hot and accept the sacrificial material. Have had zero problems.

I did do some welding on a casting once. I tore it apart deliberately and the weld held to the cast material, the cast material gave way....had casting on both surfaces where the break occurred.

 

[Sodo]

I did do some welding on a casting once. I tore it apart deliberately and the weld held to the cast material, the cast material gave way....had casting on both surfaces where the break occurred.

Welding cast is exactly THAT. There will be cracks (in the cast portion, not the mild steel) immediately upon cooling. So it's ready to break (pre-cracked) as soon as you're done with the weld. Thats why it's best to heat the casting up to a dull red before welding, and let it cool slowly as possible, perhaps even putting the torch on it to keep it dull red after the weld too (to slow the cooling/cracking). The mild steel weld never cracks, its the cast that cracks.

 

[BufordBoone]

I've been learning to weld. Guy that is teaching me told me to start with stick because MIG would be much easier and stick will do thicker and dirtier stuff...like rusty farm equipment.

He recommended a Lincoln 210 MP as "probably the only machine you'll ever need.

I've had my frustrations with stick welding but am improving. Today I decided to set my machine up for self-shielded MIG and to try it out.

WOW is this ever easier!

This morning I had trepidation about my ability to do things like add metal to the top of an old bush hog or install hooks on my tractor bucket. I was worried about burning thru the metal and then what would I do? (more metal, obviously).

Now I think those are jobs I can tackle with less fear of screwing up my equipment.

I see the value in stick welding. I like the challenge of learning stick welding. I plan to keep practicing.

However, I'm VERY glad I tried MIG welding with my machine!

What a blast!

 

[4570Man]

Sometimes it’s difficult to do a proper cleaning job so I’ll stick weld it. Stick is more flexible on location. Otherwise I mig weld it.