[Adam's Got Skills]

Hey guys I need some help. I've been welding for a couple years but have not done much mig welding. This summer I decided the job I'd chosen wasn't for me after a couple years an decided I'm going to welding school. Well I'm stuck on my destructive test on 3/32" steel...it's just mild steel. I've had my settings from 22.4 volts to 25.0 volts at anywhere 340ipm to 410ipm and all of them looked great even after it'd been so dang long. But when I break it I couldn't get good enough fusion thru the whole weld to get the steel around the weld to break around the bead. Like the last 1/4" the weld would peel off. Btw I'm using c25 and the wire was mostly .45 but I switched to .35 toward the end. The smaller wire helped but still didn't pass the test. It sucks that the instructor has so many people chasing him it's near impossible to even ask a question. Any ideas, knowledge, experience, magic, miracles, hints, or just plain HELP is appreciated!...Oh an sorry I didn't take a picture, or teacher isn't cool with phones in the shop

[Adam's Got Skills]

Btw the actual weld is a 2" stitch in the middle of a Tee Joint on the 1 1/4"x3/32" mild steel flat.

[Wes917]

This calculator is pretty good to get a rough idea on settings, then tune your machine from there

http://www.millerwelds.com/resources/ca ... ulator.php

[MinnesotaDave]

Since it's the last part of the weld, it's possible you are not staying at the front of the puddle to penetrate into the steel.

Some people call it "riding the puddle." The puddle looks nice and hot, but the arc is not cutting into the base metal.

[Otto Nobedder]

My gut reaction is that you are doing it too hot, trying to burn it in, and putting too much metal down for the heat, and it's catching up with you at the end.

Look at the chart Wes917 posted, and consider what MinnesotaDave said. It's easy to build metal and find yourself welding "on top" of that puddle, rather than burning metal in the root.

Steve S

[Adam's Got Skills]

Well I have been reading every piece of information I can find and it sounds a lot like my voltage is high but what either could be screwing me is wire speed. Cuz from what I understand the more wire you get hitting your work piece the lower your machine will drop the amperage on the downslope so even tho I keep turning up the heat it's not getting the penetration that I'm thinking I'll accomplish. Does it sound like I'm understanding this correctly? I will focus I making sure I keep it in my puddle tmrw tho either way. Thank you guys...I hadn't been so frustrated and defeated feeling in awhile. I hadn't done a lot of mig but everytime I did people told me it looked awesome at work, and I guess reality hit me today. What I thought I knew really showed me my ignorance. But II just goota get back at it and see what happens. It just sucks my instructor is SO busy it's near impossible to get any type of help.

[Adam's Got Skills]

Checked out the weldulator....I'll try those settings an see if I burn in where I need to be. Thanks ttyt

[Superiorwelding]

Adam,
My thoughts; I agree with your settings being to high and that you are probably riding the puddle. Another question is, which direction are you welding, meaning pushing or pulling. Can you do a etch test to see the difference in settings? A few pics of your welds will really help us. Also, your settings indicate globular/spray which is way to much for the 3/32", in my opinion. The C25 will not help you in that range. I believe you are on the right track, keep us posted of progress.
-Jonathan

[MinnesotaDave]

Well I have been reading every piece of information I can find and it sounds a lot like my voltage is high but what either could be screwing me is wire speed. Cuz from what I understand the more wire you get hitting your work piece the lower your machine will drop the amperage on the downslope so even tho I keep turning up the heat it's not getting the penetration that I'm thinking I'll accomplish. Does it sound like I'm understanding this correctly? I will focus I making sure I keep it in my puddle tmrw tho either way. Thank you guys...I hadn't been so frustrated and defeated feeling in awhile. I hadn't done a lot of mig but everytime I did people told me it looked awesome at work, and I guess reality hit me today. What I thought I knew really showed me my ignorance. But II just goota get back at it and see what happens. It just sucks my instructor is SO busy it's near impossible to get any type of help.

It does not sound like you understand the basics of tuning the welder correctly.

I've cut-and-paste a response I've given to another welder.

The very short version:
Voltage sets the arc length and resulting bead profile.
Wire feed speed sets the welding amperage and penetration.

It's all about the proper balance of voltage to wire feed speed.

For example, I was building some gates for a customer this weekend out of his old galvanized fence pipe, the recommended setting had a little too much voltage so it would try and blow out the thin edge of the t-joints.
Dropping to the next recommended setting down fixed the voltage issue, increasing my wire feed speed a little gave me the penetration needed.
(the recommended settings on my machine are for an input voltage of 230 volts AC, my electrical service provides 244 volts AC - so they tend to be a little hot - normally just turning down my WFS fixes the problem on thicker metal)

From Miller:
1. Material thickness determines amperage. As a guideline, each 0.001 inch of material thickness requires 1 amp: 0.125 in. = 125 amps.

2. Select proper wire size, according to amperage. Since you don't want to change wire, select one for your most commonly used thicknesses.

* 30-130 A: .023-in.

* 40-145 A: 0.030 in.

* 50-180 A: 0.035 in.

* 75-250 A: 0.045 in.

3. Set the voltage. Voltage determines height and width of bead. If no chart, manual or specifications are available for setting the correct voltage, you can try this: while one person welds on scrap metal, an assistant turns down the voltage until the arc starts stubbing into the work piece. Then, start welding again and have an assistant increase the voltage until the arc becomes unstable and sloppy. A voltage midway between these two points provides a good starting point.

There is a relationship between arc voltage and arc length. A short arc decreases voltage and yields a narrow, "ropey" bead. A longer arc (more voltage) produces a flatter, wider bead. Too much arc length produces a very flat bead and a possibility of an undercut.

4. Set the wire feed speed. Wire speed controls amperage, as well as the amount of weld penetration. A speed that's too high can lead to burn-through. If a manual or weld specification sheet is not available, use the multipliers in the following chart to find a good starting point for wire feed speed. For example, for 0.030-in. wire, multiply by 2 in. per amp to find the wire feed speed in inches per minute (IPM).

arc volts effect

arc votage effect.GIF (33.25 KiB) Viewed 1577 times

wire feed speed chart

wire feed speed chart.GIF (21.83 KiB) Viewed 1577 times

[Adam's Got Skills]

OMG!! I can understand that! My instructors can't or won't really answer any of my questions really it's weird I'm trying to learn but I'm just not getting anywhere. After listening to all this advice I actually passed my break test! Which made me pretty happy after working all day yesterday with nothing more than frustration when the told me I had to quit it was time to go home. I'm moving on to a Lap joint which I have no experience with. I'm really close to getting it but I'm really having a hard time being steady enough to not shake the whole length of the joint...I think it's just tiring hold the whole dang lead off the floor trying to keep it vertical enough (70-80 degrees) to flatten the weld out. Idk if I should make a new post but any tips about settings for a 3/32" lap joint or technique would be helpful. Thanks tho guys for helping me understand how the amperage works. I got to class early cuz I wanted to catch my instructor to ask him how does wire feed change my amperage (like where do I move it to get say higher or lower) and the only answer I got was yeah it does change your amperage I'll come help u in a minute...I heard this all day an never got the help. I was really kinda hoping for more from a welding class. Cuz I'll be the first to admit I don't know everything I probably should know or need to know. I guess I'll just have to try an keep going by trial an error and by asking you guys questions.

[dirtmidget33]

I'm happy to hear the forum was able to help you out. I hate to say it Adam but in my experence a lot of instructors and college courses in general are useless in the real practical knowledge to perform a task or teach a skill for a job. Some instructors teach because they can't do the job professionally. Colleges create a degree program fill it with classes they think are needed to teach theory of job then the real scam starts. They tack on useless classes that have nothing to do with degree you are seeking. All for the soul purpose of sucking money out of you to support university. I love there excuse "it makes you a well rounded citizen" Think you know my thoughts on that.
I believe skilled jobs should go back to apprenticeships. After all when you get done with school guess what your future company will prolly have you..... Do an apprenticeship. Put you with a seasoned welder to teach you the trade.

Now don't go quit school cause unfortunately in today's world some HR person is gonna be hiring based solely on degrees you have and not what you can do. So you need that degree to get in door.
I apologize guys I just don't like our current college system. I have seen some really talented people get thrown to side because they but don't have degrees. Either because they can't afford to take all these useless classes or get bored with classes they have no use for. Some of these ignored people by the HR departments are just outstanding in that certain field. What got me started on this was sounds like instructor is not doing his job TEACHING YOU HOW TO FIX THE PROBLEM. As a student learning this you are not gonna do everything perfect the first few times. The instructors job is to look at it and TEACH you why it didn't work and how to correct it.

[79jasper]

One little tip, in the booth, I'll wrap the lead around my arm, that way all the weight isn't pulling on my wrist.
Now I know it's not acceptable everywhere, just what I do.

Sent from my SM-G900R4 using Tapatalk

[Wes917]

Well I have been reading every piece of information I can find and it sounds a lot like my voltage is high but what either could be screwing me is wire speed. Cuz from what I understand the more wire you get hitting your work piece the lower your machine will drop the amperage on the downslope so even tho I keep turning up the heat it's not getting the penetration that I'm thinking I'll accomplish. Does it sound like I'm understanding this correctly? I will focus I making sure I keep it in my puddle tmrw tho either way. Thank you guys...I hadn't been so frustrated and defeated feeling in awhile. I hadn't done a lot of mig but everytime I did people told me it looked awesome at work, and I guess reality hit me today. What I thought I knew really showed me my ignorance. But II just goota get back at it and see what happens. It just sucks my instructor is SO busy it's near impossible to get any type of help.

It does not sound like you understand the basics of tuning the welder correctly.

I've cut-and-paste a response I've given to another welder.

The very short version:
Voltage sets the arc length and resulting bead profile.
Wire feed speed sets the welding amperage and penetration.

It's all about the proper balance of voltage to wire feed speed.

For example, I was building some gates for a customer this weekend out of his old galvanized fence pipe, the recommended setting had a little too much voltage so it would try and blow out the thin edge of the t-joints.
Dropping to the next recommended setting down fixed the voltage issue, increasing my wire feed speed a little gave me the penetration needed.
(the recommended settings on my machine are for an input voltage of 230 volts AC, my electrical service provides 244 volts AC - so they tend to be a little hot - normally just turning down my WFS fixes the problem on thicker metal)

From Miller:
1. Material thickness determines amperage. As a guideline, each 0.001 inch of material thickness requires 1 amp: 0.125 in. = 125 amps.

2. Select proper wire size, according to amperage. Since you don't want to change wire, select one for your most commonly used thicknesses.

* 30-130 A: .023-in.

* 40-145 A: 0.030 in.

* 50-180 A: 0.035 in.

* 75-250 A: 0.045 in.

3. Set the voltage. Voltage determines height and width of bead. If no chart, manual or specifications are available for setting the correct voltage, you can try this: while one person welds on scrap metal, an assistant turns down the voltage until the arc starts stubbing into the work piece. Then, start welding again and have an assistant increase the voltage until the arc becomes unstable and sloppy. A voltage midway between these two points provides a good starting point.

There is a relationship between arc voltage and arc length. A short arc decreases voltage and yields a narrow, "ropey" bead. A longer arc (more voltage) produces a flatter, wider bead. Too much arc length produces a very flat bead and a possibility of an undercut.

4. Set the wire feed speed. Wire speed controls amperage, as well as the amount of weld penetration. A speed that's too high can lead to burn-through. If a manual or weld specification sheet is not available, use the multipliers in the following chart to find a good starting point for wire feed speed. For example, for 0.030-in. wire, multiply by 2 in. per amp to find the wire feed speed in inches per minute (IPM).

arc votage effect.GIF

wire feed speed chart.GIF

I wanted to quote this bc it's an excellent response.

We have a saying, the devils in the X-ray, it might look great on the surface doesn't mean ish once we shoot it. I've seen a lot of good looking welds fail, some shitty looking welds pass.

[Adam's Got Skills]

I'm still kinda hoping that the schooling gets better myself. I got the weekend off obviously but I'm trying to make use of my time and just trying to memorize and take notes to help me get thru this semesters GMAW welds. I guess since I've never done a great deal of it just seems so foreign...The settings anyway...Like why would anyone make something so confusing to adjust?! I suppose job security for those that know how. I mean stick/gtaw are so much simpler! Maybe I'll enjoy gmaw after I get used to it, but personally I'd rather do anything but. So I guess my question is how long would you guys say from experience does it take to figure out the art of setting the machine????? Btw really thanks to everyone who's helped me since I've joined this forum....This has probably been one of the most useful tools I've had in the past few weeks!

[MinnesotaDave]

Don't worry, it will become automatic just by what you see while you weld and the resulting bead that you carefully inspect.

That's what you need to watch while you learn too - once you can recognize that what you see with the hood down is right/wrong based on what you need to do you're all set.

Keep at it

[Adam's Got Skills]

Thanks Dave! I'm not a quitter, and no matter what I'll do what it takes to succeed at becoming a better than most welder. I'm not giving up ever even though it seems like some people in class are already kinda talking like they don't know if they wanna take the class anymore. I think the biggest shock to me was the fact I worked for a pretty good sized company and several guys had kinda overly inflated my abilities at the moment. An after getting over the initial shock of realizing that I wasn't quite as good as I was made to believe....Well let me just relate that I survived the shock to my ego, and I'm better for it now. It don't mean I'm not any good it just means I'm just gonna have to work at it. I just gotta push myself to learn more become better....AND TRY MY BEST to not annoy everyone here with all my questions! Lol. Again something I'm very grateful for....the willingness of people with more experience than I to help other be better.....also humility...the teacher of living in real life!

[Adam's Got Skills]

Here's some pictures...any criticism is ok. Id like to hear what anyone really thinks

[Adam's Got Skills]

btw it's my fault I kept saying 3/32 they're actually 3/16"....oops.

[Otto Nobedder]

btw it's my fault I kept saying 3/32 they're actually 3/16"....oops.

3/16?

That's a big rod. I've not welded bigger than 5/32 on XX18 rod. My 3/16 and 7/32 experience is all 7024 in flat position.

Are you sure about the dimension? The most common XX10 and XX18 rods in practice are 3/32, 1/8, and 5/32.

Steve S

[Adam's Got Skills]

3/16" steel....not electrode....this was mig so it was .035 wire C25/75%AR 25% Co2 22.5 v 396ipm on the fillet and 19v with 270ipm on the lap

[MinnesotaDave]

Here's some pictures...any criticism is ok. Id like to hear what anyone really thinks

I'd say you're coming along just fine - a little inconsistent with travel speed on the laps but that will come with practice.
Then your bead profile will be same all the way - and it will fill all the way to that top edge while still having a nice wash-in at the toes of the bottom portion.

[Adam's Got Skills]

Ya know dave it's funny cuz Friday a fellow student couldn't get help from the teacher and I told him that I could try a lap and see if it helps....being careful to mention that I'm here to learn too...Idk everything. Anyway rean a bead an it was flat...except for a little crown in the middle from the c25, but u couldn't see it unless scrutinizing it. I laughed anyway after having so much trouble!

[MinnesotaDave]

Ya know dave it's funny cuz Friday a fellow student couldn't get help from the teacher and I told him that I could try a lap and see if it helps....being careful to mention that I'm here to learn too...Idk everything. Anyway rean a bead an it was flat...except for a little crown in the middle from the c25, but u couldn't see it unless scrutinizing it. I laughed anyway after having so much trouble!

I'm glad to hear you are getting it figured out

Can you clarify the meaning of your statement "except for a little crown in the middle from the c25"

[Adam's Got Skills]

Well I'd been used to mostly welding black steel with str8 CO2 and it really lays a nice flat weld/When learning about using a different gas...My textbook shows that basically C25 will be flat on the edges...An it does look flat but when you look from the side the middle has a little convex crown just in the middle...It's not much like I said it looks flat. An my textbook not saying it's right now (Cuz what I know as the "truth" Is always up for revision) it just says that's part of the difference in bead from CO2 to Ar/CO2. Am I wrong here....Cuz my book has a diagram about the difference in weld bead appearance......?????

[Adam's Got Skills]

If I remember right it said Ar shielding is more crowned then either of the other two