The welders thread (4 Viewers)

[e9999]

well, I took my own advice and called Hobart Tech support to ask some questions raised above. Here is a summary if that helps. I asked mostly about the H140 which is what I have. A nice older gentleman who has taught industrial welding and is currently a pro welder too. Very nice experience on the phone. Good company, good people IME. Here is what he said:

- the WFS will indeed affect the amperage. Higher WFS, higher A, for a "constant voltage" (me: not really with the H140) machine. Did not get a good physical explanation as to why though, despite asking more than once.
- the distance to tip ratio is very critical. He explained that on a bigger wire machine where you can actually see a big swing in current (unlike the H140), the current can vary from 150A at 1/4" distance to 50A at 1/2" distance, everything else the same. I guess that means we want to stay close if we need good penetration.
- 0.030 will give better penetration than 0.035. Another Hobart tech I talked to a while back also emphasized that.
- there is very little "real galvanized" steel still produced/used in the US today, it's mostly aluminized now instead, so the zinc fumes issues is no longer a serious problem (me: unless you work with old material of course). One can tell by the color of the weld edge.
- he's indeed using a fan when no fume extractor is available. He says if you point the fan at the work it will dissipate the shielding gas and increasing the flow rate is iffy but if aimed overhead or head level it should be fine. (me: aiming at back of head seems counterproductive given the recirc zone created downstream)
- he says he can do 3/16" fillets and butts (with bevels) in one pass with the H140 for sure. No hesitation.

 

[LFD2037]

I went back to the drawing board today. Spent about 3hrs. welding, cutting, sanding & etching. These 3 pieces are 3/16, .030 FC wire & 3 different speeds. 1 @ 30, 1 @ 40 & 1 @ 50 WFS. The machine suggests level 4 (5 is max) & a WFS of 50. I kept it on 5 (max for this machine) & 50 was the max WFS I could go w/out it being too fast & kicking back. I'm starting to think it's an operator error because I should be getting more penetration. 30 had a little penetration, 40 was best & 50 was worst. Do any of these look acceptable?
WFS 40 on top, then 30 in the middle then 50 on bottom)

 

[firestopper]

All three weld nuggets look very good considering the smaller machine. which of the three ran best and produced the best bead (appearance)?

My 350P miller in pulse mode, the WFS controls the amperage, but in conventional MIG, the heat is set by voltage. I have always been able to adjust the heat while welding by increasing the distance of the tip to work of small gaps (colder) verses closing in for more heat. This works great when welding irregular joints on certain applications.

LFD2037, I assuming your torch (gun) is set up electrode negative for running flux core...yes? Pushing or pulling while welding makes a little difference in penetration. I mostly MIG, Flux core using the push method as my eyes aren't what they use to be and I can maintain sight of the joint, but I always run hotter than recommended. I like the beads to "wet down" without undercut. Travel speed comes with practice. Over all, I think you machine has proved that 3/16"is doable on single pass. Anything much heavier will require a bigger machine IMO.

 

[LFD2037]

@firestopper
Yes, set up neg. for FC wire. Since I'm using FC wire it's drag only, no push (if there's slag, then only drag!). That is so good to hear that the weld nuggets are acceptable!!!!! I've been stressed about this while dang deal. I'm ready to start welding real stuff instead of all this practice I've done for weeks.

 

[firestopper]

@firestopper
Yes, set up neg. for FC wire. Since I'm using FC wire it's drag only, no push (if there's slag, then only drag!). That is so good to hear that the weld nuggets are acceptable!!!!! I've been stressed about this while dang deal. I'm ready to start welding real stuff instead of all this practice I've done for weeks.

If you want to see how strong those weld are, start off with two 3/16" thick 4"x4" flat strap. Bevel slightly and form a butt joint leaving a small gap. weld up the butt joint, then cut 4 strips out perpendicular to the weld joint. You can now bend the 4" strips 180 degrees (in half) and witness the weld joint. I think you'll be pleased with the results. If your joint requires multiple passes, clean very toughly between passes to ensure a porosity free joint.

A word of caution, know the machines limitations. When welding hi stressed joints such as spare tire carriers,bumpers and such. A larger machine might be in order.

Clean very thoroughly is what I wanted to write...Auto correction is my worst ENIMA! haha

 

[LFD2037]

I welded more this evening. I tried welding it at the manufacturers settings and it didn't penetrate and it spit and sputtered and looked awful. I think I'll stick with the colts on 5 and WFS on ~38-40. Once I get gas I'll have to redo all my research but that's okay. I will be welding a 4x4 Labs rear bumper but for the majority of it I'll use my cousins big Miller. For the hitch attachment and recovery points I'll have him weld those as he's acclimated to welding roll cages and the like. Thanks for all you input brother.

 

[e9999]

I'm surprised to read you say that the suggested settings are not right. I have done a bit at 3/16" and I thought the suggested settings were good. Never any spitting and sputtering if I did my part. Very smooth arcs and good beads. Something not quite correct someplace?

 

[LFD2037]

I'm surprised to read you say that the suggested settings are not right. I have done a bit at 3/16" and I thought the suggested settings were good. Never any spitting and sputtering if I did my part. Very smooth arcs and good beads. Something not quite correct someplace?

Are you running gas or flux core? If gas, what mixture? If flux, volts on 4 and wire speed of 50?

 

[e9999]

done both but more with FC recently. With gas was 100% CO2. The settings per chart were good I thought, never had to deviate much if at all. Have to fine tune travelling speed and holdoff distance of course. Been thinking that the HH140 really gives good arcs. I suppose the latter is subjective but I get the nice frying bacon sound all the time. Main problem I have is that I must be half-blind evidently and can't see where I'm going half the time...

 

[LFD2037]

done both but more with FC recently. With gas was 100% CO2. The settings per chart were good I thought, never had to deviate much if at all. Have to fine tune travelling speed and holdoff distance of course. Been thinking that the HH140 really gives good arcs. I suppose the latter is subjective but I get the nice frying bacon sound all the time. Main problem I have is that I must be half-blind evidently and can't see where I'm going half the time...

Have you cut any welds apart & checked penetration? I can lay down some pretty (for FC wire) beads, but they weren't penetrating near enough. I tend to overthink things so I had to do further/deeper investigation into my welds. OCD I guess, IDK. I just want to make sure when I'm driving down the highway I'm not dropping parts off my rig & endangering someone else down the road. If you're going by the advised setting (from inside the door of the welder) & you researched good penetration then I must be doing something else wrong. I've noticed I need to be ~6-10" from the weld, & a bit to the side, to really see my work.

 

[e9999]

no, not done cutouts etching and all but I ground some beads into the base material and they looked fine. Remember there is a difference between fusion and penetration, no need to melt metal deeply in the base plates to get good fusion at the interface. But anyway, as I'm no expert welder by far I don't plan on welding anything critical on my truck or trailer any time soon.

 

[hairy_apple]

My latest project. Made some rad top plates for my buddies ugly tube bumper. They came out rad. Finally got to start welding again after almost 3 months of being laid up from shoulder surgery.

 

[LFD2037]

no, not done cutouts etching and all but I ground some beads into the base material and they looked fine. Remember there is a difference between fusion and penetration, no need to melt metal deeply in the base plates to get good fusion at the interface. But anyway, as I'm no expert welder by far I don't plan on welding anything critical on my truck or trailer any time soon.

Like I said earlier, I'm sure im overthinking this whole situation!!!! I wasn't throwing accusations, I was just inquiring. I appreciate any input you have seeing as you're running the same welder as me. Thanks!
*ETA* What's better, fusion or penetration? Or do they not have anything to do with each other? Thanks.

 

[e9999]

LF, I think it is best to let somebody who went to welding school and knows more about this than I do to explain how this all works. But I'll conjecture -thinking aloud and worth what you paid for it- that in principle one could have very good fusion (as in good melting and commingling of filler and base) with very little penetration (as in small depth of fusion perpendicularly into the base material from the original free surface) and that it would still make a good weld locally in the sense that you have one solid piece of material there comprising both filler and base material with no void between the two (although the "overall joint" may not be strong if there is little bead material or fused area, of course, depending on the geometry). Picture a flat overlay bead on top of a flat plate with a very thin region of once-melted base metal underneath the bead but with no void or gap between the two, to visualize what I'm trying to say. Now, in reality it is of course likely difficult to achieve that blindly so one may want a good deal of penetration to ensure good fusion everywhere needed, overkill to be safe, so to speak. So in that sense, more penetration would be good. (I'm talking about penetration perpendicularly into flat surfaces here, not as in the depth down into butt joints gaps etc.) IOW, I think you can possibly have good fusion -what you'd want- without a lot of penetration but that OTOH a lot of penetration will more likely give you good fusion, so we want to do the latter to be safe. (I hope no high-schooler reads this, I can see all the chuckling already...)
But I'll further conjecture that there are, however, also cases where you don't want deep penetration because of issues such as recrystallization, inhomogeneous shrinkage, diffusion of alloying elements and what not, although likely not issues that novice welders like myself have to worry about yet.
I didn't study the topic so the above may be all wrong. I need to do some reading for sure. And sure wish there was a place locally where I could take a welding class.

 

[firestopper]

Sorry to interrupt the welding class, but it's time for a brake. Although not much welding on this project (just a little TIG steel/alum), I thought I would share. 2015 four seater Razor (not mine) required a roof. The customer had no idea what look he wanted and gave me design freedom.

Started out with cardboard templates (standard) and transferred to 1/8" aluminum (5053). This alloy allows breaking without cracking and welds up nicely. I also added a 36" LED light bar requiring light wiring. Its switched to the hi-beams so no extra switch required. The brackets are milled slotted for fine adjustment and tig welded to the Dzus bracket. The rear roof panel required two small welds as well.

 

[GLTHFJ60]

Have any better pictures of the steel to aluminum TIG welds, and maybe which filler rod you used for that?

 

[firestopper]

Have any better pictures of the steel to aluminum TIG welds, and maybe which filler rod you used for that?

Sorry, I'm a fabricator not a writer. The Dzus brackets are mild steel and the roof panels are aluminum. Thank you for busting my chops haha!

 

[Weber Sarge]

Surface fusion is worthless for strength - it's basically the same as brazing or soldering . A true solid weld mixes deep enough to make the joint into one mixed piece and stronger than the surrounding metal .

One note about those smaller migs - most have the crappiest ground clamps available , switching it out to a heavier clamp and making certain to put it on very clean , freshly ground metal helps a lot with putting the full force of the arc into the material . Pay very close attention to stick out at the nozzle and hold a tight arc , always stay on the leading edge of the puddle as this is critical to penetration . Maybe spend some time over on Collier's site and watch some of his mig videos - he explains in great detail and has some of the best arc shots I've ever seen , learn new things from this guy all the time and it helps even those like me that have a lot of welding years under the belt .

Sarge

 

[LFD2037]

@e9999
Damn fine explanation. Thanks!
@Weber Sarge
If by Collier you're talking about weldingtipsandtricks.com then boy have I spent some time on there. All BS aside, I've spent over 20 hrs. reading posts/advice/questions/suggestions & watching videos in the last few weeks. When you, & everyone, say leading edge of the puddle:
am I actually supposed to be out front of the molten metal w/the wire tip? As in slightly outrunning the weld the whole time? I'm off to watch more videos!

 

[Tapage]

When you, & everyone, say leading edge of the puddle:

short reply .. yes and Jody it's da man .. not saying it's the best welder .. but taking the time to upload those good videos it's absolutely nice ..