MIG vertical up trouble

[Shield Arc]

Charts are like instructions, I only look at instructions when all else fails!:laughing:
First thing I think you need to do is turn the wire speed way down. Or the volts way up, but if you turn the volts up, you may not be able to handle the puddle.
When running wire feed vertical up, I build a shelf first. The width of the shelf determines the width of the bead. Once I have my shelf built I point the gun straight into the plate, or even slightly down. The whole time I let the puddle lay on this shelf I built. As you travel upwards, remember to raise your shoulder! Keep the gun angle consistent, and the arc length consistent, and your travel speed consistent! Move side to side, pause only long enough to let he puddle fill to the amount you want, then move quickly across the middle and pause on the other side long enough for the puddle to fill. Repeat as many times as necessary.
Here is a good video on welding vertical.

Mig Welding Techniques for uphill welding

 

[Shield Arc]

I forgot to mention, what I like about Jody's upside down V. Is when you put the first pass in, (root) most of the time you don't have a lot of room for side to side movement. I can see where his technique would be very beneficial in getting the root really dug into the crotch of a fillet weld.

 

[Gary Fowler]

The only time you should run MIG downhill is when running an open butt root pass or when on thin material and all you want is a seal pass. For filling a V groove or running a fillet always run uphill. Shieldarc seems to have it down and his instructions are perfect. In the photos of the dripping weld, it is obvious that your are not hesitating on the sides and concentrating your wire feed in the middle of the weld. Also in all instances you are travelling too fast, you need to keep the wire in the puddle more and use a consistent oscillation an travel up speed. Notice how smoothly the ripples blend in on SA's weld and how each on the SDTIG welds have a valley between each mountain. Hold on the sides till the undercut fills up then zip across the middle at a fast clip to hesitate for a 1,2 count or longer till the sides fill in. If it helps, do a count 1,2,3 on the sides then 1 across the middle then hesitate for 1,2,3 count on the sides. Depending on the voltage and wire speed you may need only a 1,2 count but hopefully you will get the hang of it. By the way, the same holds true for stickrod uphill. Angle of the gun is important also, when running downhill you have to point the gun slightly up into the weld puddle and keep the wire feeding into the puddle. If you go too fast or slip out of the puddle, you are going to have whiskers of wire all inside or on the backside of your weld. I think SA already covered the gun angle going up hill on the filler passes.

 

[dstig1]

SA - Thanks for the tips. The video is very helpful too. A big thing I noticed is his settings were much lower than mine. He said about 18v, 200 ipm on 035 wire whereas I was at 22v and 400 ipm for 035. The only difference is he appeared to be using 1/4" plate vs my 3/8", but I'm not sure on that - he may have used 3/8" I just wasn't sure. In any case, I think I need to really dial down the welder a bunch, for starters.

Gary - thanks for the tips. You are saying the kind of things I was trying to do, just unsuccessfully. But I strongly doubt I was traveling too fast as any slower and it got far worse.

Biggest problem I have with MIG is I can't really see the puddle with the nozzle in the way. I can see it a bit in the right orientation, but it isn't great. I found stick much easier in that regard as there was a lot less stuff in the way.

I'll give this stuff a try when I find some more free time to get out there.

Thanks again.

 

[Shield Arc]

Biggest problem I have with MIG is I can't really see the puddle with the nozzle in the way.

Generally I don't have that problem, but years ago I got elected to fill 13 holes that were 13/16" in dia. Each hole was drilled half a hole off! In a 2-inch thick plate! Each hole had to pass UT inspection after I filled them up. The hard part was this 2-inch thick plate was a sole plate that was already installed in a concrete bridge abutment. So all the holes had to be filled from the top. The local welding supply suggested I use a nozzle like this so I could see around it inside the hole. It did help, but the first 3/4 inch or so I could not see, I had to weld by sound. Back then I must have been living right, all 13 holes passed UT inspection!:shocked:

 

[LD1]

Well, I'll throw in my in-experienced :2cents:

We dont do much vertical welding. And even when we do, strength isnt really critical. Other things will bend or break far before the vertical welds even if crappy.

All that said, when we do have to do vertical, or just messing around like you are, it takes me quite a few trys just to get the right settings to look acceptable. And even then, I sometimes get that crown look like you showed there in the first pic of post #20. But I can tell you (from welding and breaking things) that a weld that looks like that isnt necessarily a bad weld. Infact, I have made several welds like that that penetrated as well as one could expect, the only problems was purely cosmetic. In cases like that, where I know I have made a good weld, but it just dont look quite good, running a vertical down cap pass over that makes it look good, and is just as strong as if you could have gotten the good look on the first pass.

And I agree with the others that say DONT do vertical down if it is thick material. From messing around and breaking welds appart, you get absolutly ZERO penetration doing a vert-down. The only thing holding the weld is simply the fillet of the weld itself. Whereas vert-up you get the base metals fused AND have the fillet. WAY stronger.

 

[Gary Fowler]

Gary - thanks for the tips. You are saying the kind of things I was trying to do, just unsuccessfully. But I strongly doubt I was traveling too fast as any slower and it got far worse.

.

What I meant by going to fast was the vertical speed compared to the side to side ocillations. Look at the bead SA did with the tight weave compared to the peak and valley between the side to side ocillation. You need to double the side to side weaves in the same space of vertical climb. Now it looks like you are doing one side to side motion for every 3/8" of travel. Try increasing the side to side by double or even triple the number. The more ocillations you make per inch of travel forward/up the closer the weld puddle ripples will be and te smoother the weld. This is also true of stick welding/

 

[dstig1]

Time to resurrect this... with the warm weather, the garage is bearable to work in now. And I had a bit of time. I went and watched Jody's video that was referenced above, and the settings he said blew me away. 18v and 200 ipm on .035 wire. Compare this to the slider chart from Miller I have that says 23-24V and 420-520 ipm on .035 wire. for 3/8" steel. Those are like night and day, and I can see why I was having so much trouble - waaay too hot. So I tired his settings to start. Seemed a bit cold at first so I upped it a bit to 18.5V and 240-250ipm. Then I upped it another step to 19.1V and ~275ipm. That last step seemed to be about right and it actually came out not too bad. A little lumpy in the center, but seemed OK, and certainly a lot better than the previous attempts. Here is a pic. The upper half is the 19.1v setting, the lower half is the 18.5V setting. This was a second pass over the top of the 18 V setting. Both pics are the same, just with and without flash. I should have watched the video just before doing this and perhaps the technique would have improved (I watched it a long time ago, but only remembered the settings). Still need more practice, but this at least gets me much closer to being able to make it work when I need to.

Thanks again for the help guys!

 

[Shield Arc]

Everybody has their opinion, so take my advice with a grain of salt!
I have a policy when Mig welding, I run as hot as I can handle it. In my opinion the biggest problem people have with Mig welding, is they run too cold! Then wonder why things fall apart.

 

[CNC Dan]

shield arc makes an important point.


Don't be afraid to adjust the wire speed while you weld. Or have someone else do it. You can tell a lot from the sound of the arc as the feed speed is changed. I think ChuckE2009 did a video not too long ago where he did that.

Also, remember that things change as you test piece heats up.