Help... Need Welding Advice

I have a nice setup....a Miller 210 MIG. Probably too good for me since I suck at welding. Anyway, I seem to be getting strength, but the welds look just awful. So, I need some advice. Assuming that the chart on the welder is correct concerning heat and wire speed, how do you determine the correct amount of wire sticking out of the gun verse the thickness of the metal being welded? Or does that not matter? How close should you keep the gun to the welding line? Should this vary by thickness of the metal being welded?

Right now I'm spending a lot of time with 1/8" mild steel 2 x 2 box tubing. Seems too easy to melt a hole in the tubing unless I move rather quickly. Too much heat? Dah, I don't know.... Moving quickly must not be good for penetration.

I know, I guess I could test different methods, but, I'm looking for instant gratification from the collective wisdom of you welding sages out there. Can't beat experience.

I'd like to get to the point that I can weld frame components and not be worried that my car will break in two while driving down the road.

Thanks in advance.

Gary

 

I have the same welder. It came with a video that gave some good general info to get you started. But I'd bet you're holding the torch too far from the surface that you're trying to weld. And you might also have the angle of approach wrong. I found the set-up data under the top cover to be pretty deadly for accuracy.

 

What kind of gas are you using?

 

Go to millerwelds.com Miller Electric has an updated site with a questions and answers section that might help out.

 

The metal thickness doesn't matter. Keep your wire about 1/4" to 1/2".

You can actually drag the cup, if you have a good insulator on the gun and no spatter build-up. Otherwise it'll arc.

Holes mean too much heat, and maybe too much wire.

What are you building right now...? I'm really interested in knowing.


JOE

 

Gary,
when you get the heat/wire feed deal right the sound should be like frying bacon--a constant sizzle. If you are welding a tubing "t" keep the wire biased towards the crossbar of the "t" as it will absorb more heat than the leg. Just the reverse if you are putting a thick bracket on thinner tubing. The trick is to balance the heat so that both components get enough to allow the molten puddle to fuse them without blowing holes.
Mainly you need to be in a comfortable position to weld so that you can guide the gun smoothly. If necessary use a block of wood or whatever as an armrest and set yourself up so that the welding motion is smooth. I usually use both hands, one to actually grip the gun and the other to steady it as I drag it through the required motions.

Roo Man

 

roo man's right. if you're not comfortable enough to make the whole weld, you're gonna struggle. that's what makes "out of position welding" such a pain in the ass (lately it seems that the engineers at work have a jones for this shit). anyways, it should sound like bacon, and remember, don't hold that gun TOO far away from the metal. the closer you are to the metal, you will have slightly more heat. i think it's funny to see guys with thier power sources turned up to 11 & they've got 2" of stick-out on the wire! you'll just have to play with it until you find the settings that work for you. for frame type work, i would run the thing a little hot anyways just to make sure i got good penetration (18-19 volts).

 

oh yeah, use c25 gas.

 

Still wondering about the gas. When you say "the welds look just aweful" what are we talking about here. Are they porus looking (sorta like foam), are you not getting that role of coins look? What does it sound like when you weld? What size wire? It could be as simple as you just not having the correct shielding gas. Take a picture and post it and we can probably tell you right off the bat what is up. That would be the best way.

 

Also watch your puddle as you weld to get good coverage. That will determine how fast you move.

 

Welding takes practice. Practice a bit and then pracitce some more.

 

Sounds like you have it too hot. Don't go faster to avoid blowing thru the metal - you'll have poor penetration. Torch angle is important. You want to be at about 75 degrees, about 1/8-1/4" from material. The closer you are to 90 degrees, the hotter the molten pool. When you grind the weld down, how does it look? Can you see the back of the weld to check if you are getting 100% penetration?

MIG is fairly easy, you'll get the hang of it. Get some scrap & practice, practice, practice.

 

All the above suggestions from the other guys are great.

Assuming that you have the settings right and you are push welding (welding from right to left if you are right handed), another thing I would add is to concentrate on watching the LEADING EDGE of the weld pool. What you want to do is create a small puddle of molten metal and then move the leading edge of that puddle along steadily -- making sure that the pool is melting away at both sides of the joint equally and move it along. If you have a nice clean lens on your helmet and you really concentrate on watching the leading edge of the weld pool as it moves along at a steady pace and keep the pool centered in the joint and a consistent width, you will probably wind up with really nice looking welds. Use both hands to keep your hand steady. Make a trial run without pulling the trigger to make sure your hands or elbows aren't going to bump into something. Angle yourself so that you can get a good view of what you're doing.

If you start doing sheet metal. Make lots of short welds. The heat just keeps building up and you'll just blow a big hole if you try to run a really long bead in sheet metal. It's better to do dozens of 1/4" or 3/8" long beads than to try to do a really long bead all at once.

You can use the stickout length of the electrode wire to control the heat during a weld. At the beginning of a weld, you want the gun in very close to get the maximum amount of heat, but as you progress, you can pull back slightly to cool it down so that you won't blow a hole. If you are welding towards the ends of two pieces of metal, you need less heat at the end of the weld so you can pull back slightly to give more stickout at the end of the weld so that you won't just blow a big hole in the ends of the pieces. I think the usual recommended stickout is about 7/16".

Oh, one thing I thought of that a beginner might experience is that you have to weld where there is no wind. If just a slight breeze blows the shielding gas away, the oxygen in the air will burn the molten steel and it'll come out brittle and porous and full of bubbles. Having dirt and garbage on the steel will also cause bubbles. Grind away ragged edges and clean off oil and grease from the edges near where you're going to weld. If you weld way too hot, you'll boil the steel and cause bubbles and you'll see things that look like volcanos spring up out of the puddle of molten steel. If your welds are too cold, they'll look ropey -- like a little trail of turds just lying on the steel instead of flowing into the parent steel. If it's too hot you'll see craters in the parent steel at the edge of the weld bead.

Maybe if you could show us some extreme close-ups of the ugly welds, we could probably tell you what you're doing wrong.

Have fun practicing.

 

Try e70s3 wire .030 diameter. 75/25 Argon /Co2 mix.
Get the gun right into the work so you form a nice puddle. You will have to adjust your wire speed and voltage to get a nice consistant penetrating weld. It should sound like bacon frying in a pan when everything is working properly.
Spend some time welding on clean scrap until you get good results. In class "A" school we stick welded over and over on the same chunk of stock weld on weld. When you get to feeling good about what you see; cut it in half and see what the core looks like. Good homogenious welding will produce solid iron with no porosity or inclusions.
PanheadGuy

 

I knew I would get some great feed back from you guys.

I'm using 75/25 Argon/CO2. Wire size is .30.

It does sound like bacon frying. But, I seem to get a lot of spatter. I think most of my issues (aside from trying to get comfortable) is angle and distance from the joint. Some times the welds look like a row of dimes and sometimes it's kind of a gobby mess. I haven't really ground down the welds when complete except for undoing a tack.

Right now I'm not building anything really critical. I have a Corvette race car that I need to sell and it's currently completely disassembled. Since you lift the body off the power train, I'm building a rolling power train dolly to hold the motor, torque tube, trans and rear (plus some of the suspension components). I thought this would be good practice. Once that's done, I can lower the car onto the dolly and 8 bolts later it's almost drivable.

I've been mainly using tack welds and then going back to complete the welds when I think it all fits. I do have a really hard time seeing my welding line. I've also been welding left to right. Maybe I should try pushing along. My auto dim helmet helps and I've set the lens to 11.

Can't post any pics yet but will try soon.

Thanks again.

Gary

 

I'd set your lens to 10 for MIG, it will help you watch the weld better. My welding instructor told me that 11 is better for TIG where you have a really bright arc.

 

Watch the puddle. It will tell you what to do. Lots of spatter sounds like high voltage or not enough gas coverage. Wind and fans do a good job of disrupting your gas coverage

 

Yeah, everything they said.

The spatter could be due to too much heat, but if some welds look good and others don't, then I'm guessing you're having problems with little breezes blowing away the shielding gas, or the steel is greasy or dirty or rusty. If you cut some steel with a chop saw, grind away the little "flap" or "flash" of steel that's left hanging on the bottom of the cut. That little flap is full of garbage and since the little flap is so thin, it boils in the arc, which will make it splatter a lot. Try cleaning up the steel a little better and grinding away any loose little shreds of steel hanging off the edges. A zirconia abrasive flap disk in a 4-1/2" grinder works great to clean up the edge of the steel quickly prior to welding without roughing it up much at all.

A little bit of spatter is normal. Try using a 50 grit disk in a 3" right angle die grinder to grind away the spatter. It knocks off the little balls of spatter quickly without hogging away any of the bulk of the steel like a hard grinder disk would.

Also get one of those three prong Mig nozzle cleaners to scrape all the junk in your nozzle out once in a while. And change the tip once in a while. Check to see if your wire is rusty. If you have wire that's been sitting around in a damp area, it can get rust spots all over it even if it's the copper plated wire. Wire like that with rust spots on it is junk and you should get rid of it if it's like that.