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View Full Version : How to adjust MIG wire speed/voltage?



rufus
03-24-2006, 05:56 PM
I just watched a TV show "V8TV" where HTP gave a newbie first MIG lessons. Here's what he said. To paraphrase;

Welding 1/8" or so medium steel, solid wire/gas.
To set wire speed hold the gun with the nozzle in contact with a test piece of steel similar to the work piece at an angle ~45deg. and pull the trigger and without moving the gun adjust the wire speed for proper sound. (no popping due to insufficient or excessive wire feed) Sort of somewhere in the middle of the two.
The proper wire speed is when you get the magical sizzling sound.

I understand what he was describing, but he failed to talk about how to establish proper voltage setting, I would think the voltage setting would be selected first then adjust the wire speed. Am I correct in thinking voltage setting is determined by work thickness?

I need to do a lot of sheetmetal repairs, blow through is a big issue. If I select the voltage properly (not sure how I do that other than thickness charts) is the process for setting wire speed vaild, just using short pulses to keep the work from getting too hot?

I know trial, error and practice is the way to learn it but sometimes I feel I'm spinning my wheels. (and running out of coupons)

Set me straight on this blather...

hankj
03-24-2006, 06:09 PM
I'm somewhat confused by the terms "torch" and "cup". That's TIG to me. MIG uses a gun, and the end of it is called a nozzle, I think.

Settings depend on the machine. A little 120V machine will need higher settings than a 200-amp version for similar work. Most machines come with some sort of chart or guideline for initial settings; you fine tune from there.

I don't know how one would hold the gun in a proper welding position, pull the trigger, then reach over to the welder and twist knobs! It's beyond me. I start by setting up at the machine's recommended setting for the material, and run test beads, tweaking as I go. Voltage generally controls bead profile, while wire speed controls amperage (heat, as a lot of guys like to call it!). Of course, for any given voltage setting, there are limits to how much wire you can burn off.

Sheet metal is a whole different act. It's very difficult to run continuous beads without either burn-through or sever heat distortion. For me, it's slow and easy - tack or run a mini-bead, pause for cooling, repeat. I'll work from both ends, too. Run a bead at one side, go to the other side and run a bead, go back to side 1 and repeat, etc.

Practice on some similar pieces before you go for the gusto! The thinnest I've successfully run continuous beads on is 16 ga.

Good luck.

Hank

rufus
03-24-2006, 08:43 PM
Thanks Hank, I corrected the terminology.
Watching the demo adjusting the spreed while pulling the trigger actually looked simple. Once the gun was positioned the operator pulled the trigger and started adjusting the wire speed, still not looking at the arc just listening.

I'm gonna melt some steel tomorrow to try it out. I guess for my HH-175 I'll turn it low as it will go for the sheetmetal and use little spot welds to keep the heat down.

Sundown
03-24-2006, 09:01 PM
<snip>I don't know how one would hold the gun in a proper welding position, pull the trigger, then reach over to the welder and twist knobs!<snip>

Whats the matter Hank, don't you have an extra set of eyes outside your helmet and a third hand with two fingers to adjust while running a bead? I wonder what Jeff was thinking, if in fact he was involved in this lesson. :confused:

TOMWELDS
03-24-2006, 09:12 PM
In the past, ive always started with the chart settings...ive wondered if there's a formula, like with stick or tig?

wworks
03-24-2006, 10:18 PM
yah defiantely with the 175 you want the lowest tap #1. do you have flux core or gas? whenever i use flux core on sheetmetal burn through is a big problem so im geussing youll have better if you have gas. for starters probably put wirespeed somehwere aroun 10

hankj
03-24-2006, 11:25 PM
Whats the matter Hank, don't you have an extra set of eyes outside your helmet and a third hand with two fingers to adjust while running a bead? I wonder what Jeff was thinking, if in fact he was involved in this lesson. :confused:

♪♫ "Oh, Lord, wontcha buy me a Mercedes Benz.....♪♫.

Nitenite!

Hank

Sundown
03-25-2006, 12:31 AM
♪♫ "Oh, Lord, wontcha buy me a Mercedes Benz.....♪♫.

Nitenite!

Hank

Oh yes, I too remember JJ ... when I start with that my kids think I am nutz, pleasent dreams :cool:

jbmprods
03-25-2006, 01:14 AM
Oh yes, I too remember JJ ... when I start with that my kids think I am nutz, pleasent dreams :cool:
oh yes the fond memories of the 60's **** we're old. mattera fact i just turned senior citizen member ..... i want my discount:cool:

Mike W
03-25-2006, 04:24 AM
Look way down this page for the "clock method". http://www.weldreality.com/short_circuit_under100.htm

rufus
03-25-2006, 09:55 AM
The "sound test" for wire speed is done on a test piece of steel. Not the work. I did'nt make that clear originally.
I'm reading that you guys don't think much of that technic?

Stay on task guys, no pickin' on the old folks.
Of which I am getting close to.

Thanks,
rufus

SCHOONER
04-02-2006, 03:57 PM
Look way down this page for the "clock method". http://www.weldreality.com/short_circuit_under100.htm

MIKE

Just a word of " THANKS " for posting that great welding site.:)


Man, is this 65 yr. older still learning ~ Thanks to you Mike :) again 4 sharing that site.

Mike W
04-02-2006, 04:08 PM
Hi SCHOONER, you are welcome. I am glad that you found it interesting.

stang
04-06-2006, 09:03 PM
not a good welder for that type of metal, because its a tap machine, not alot of room for adjustment, try a miller, you'll love it, and can sell the HH easy, to a farmer or hobby type,

Broccoli1
04-06-2006, 11:53 PM
not a good welder for that type of metal, because its a tap machine, not alot of room for adjustment, try a miller, you'll love it, and can sell the HH easy, to a farmer or hobby type,

?

I used a Lincoln Weldpak 100 with Solid wire and gas- which is a tapped machine and it worked just fine.

No need to sell the Handler:D

eddie
04-07-2006, 09:07 AM
[QUOTE=rufus]I just watched a TV show "V8TV"

Is this on your cable TV or satellite? I'd like to see if I can pick it up.

thx

hankj
04-07-2006, 12:05 PM
not a good welder for that type of metal, because its a tap machine, not alot of room for adjustment, try a miller, you'll love it, and can sell the HH easy, to a farmer or hobby type,

What do you base that conclusion on?

I have both types, and I can adjust my MM210 (tapped) to weld sheet metal no sweat! The smaller HH-series machines are noted for their ability to weld sheet metal, too! Don't forget the wire speed tracking feature in the little machines!

I really don't see a need for infinite voltage capability until you start getting up into spray transfer setups. In fact, I like the taps better on the 210 than the infinite adjustment on the 135, but, again, that one is a tracker, too.

Hank

rufus
04-08-2006, 10:38 AM
Eddie,
I have Dish Network, the show is on the Men's channel. Here's a link to the website.
The show is pretty lame but once in a while you see something interesting.
http://v8tvshow.com/

Take a look under the TECH section and you'll see the MIG write up from the show.

eddie
04-10-2006, 04:55 PM
Thanks, rufus.

I have Direct TV...looks like it's not offered.

Portable Welder
04-11-2006, 03:52 PM
Heres how to set a machines, First of make sure you have proper wire tension by holding the wire after it sticks out of the gun, You want the tension set where you can just barely stop it, that way its not overly tight.
Setting your heat which is the voltage knob you have to estimate your heat your thickness chart on the machine can help you adjust your heat which is voltage, now you are ready to adjust your wire speed rate, start welding on a pc. of scrap that is close to the thicknes that you want to weld, put one hand on the wire feed knob and flip your shield down and start welding and listening to the crackle when you get a nice constant crackle then your wire speed is set.
Dont make the mistake of turning your voltage control knob while you are welding because doing so will eventually ruin your machine.
It is only OK to turn the wire speed knob while welding.

Portable Welder
04-11-2006, 03:56 PM
One other thing I forgot to mention, when you are doing over head welding with mig, I will turn my wire speed up a little higher than I would than if I wre welding flat.

Broccoli1
04-11-2006, 04:04 PM
It is only OK to turn the wire speed knob while welding.

Porty,

On a tapped machine!!!

but on my 135 Plus I can do both:D :D

halbritt
04-11-2006, 05:08 PM
I've started using this technique and I've found that I can get a nice short arc dialed in very quickly on steel. I wonder if there is a similar technique that one can use with aluminum doing spray transfer? I was playing with my spoolgun the other day with some .030 4043 on 1/4" plate and had the hardest time getting it dialed in.

hankj
04-11-2006, 06:48 PM
[QUOTE=Setting your heat which is the voltage knob .[/QUOTE]

I have trouble with the notion that voltage = heat. Maybe I'm wrong, and I'm sure somebody will tell me if I am, but I see "heat" as the currnet flow to the work. To me, wire speed = heat. The faster the wire runs into the weld pool, the more current (amps) is needed to burn it off. Heat.

Of course, there is only so much current (wire speed) available depending on where you set the voltage, so I guess the two are married. Stll, for me, heat be amps!:p

Hank

halbritt
04-11-2006, 07:28 PM
I have trouble with the notion that voltage = heat. Maybe I'm wrong, and I'm sure somebody will tell me if I am, but I see "heat" as the currnet flow to the work. To me, wire speed = heat. The faster the wire runs into the weld pool, the more current (amps) is needed to burn it off. Heat.

Of course, there is only so much current (wire speed) available depending on where you set the voltage, so I guess the two are married. Stll, for me, heat be amps!:p

Hank

I could very well be mistaken, but I believe the total heat in a weld is the result of both the voltage and the current, which makes the most sense to me from an electrical perspective. In either case, assuming the resistance of the welding circuit is fixed, additional voltage is going to increase current as well per Ohm's law. Theoretically, I suppose it could simply be the amount of current, but that's still going to be directly related to voltage.

In the GMAW process, all the parameters have an effect on the weldment. It takes a fair amount of experience to determine the appropriate parameters. I don't have a door chart on my welder, so I generally just guess at the initial voltage (or use Miller's welding calculator and measure the welding voltage). Following that, I'll dial in the wire feed speed to get a nice arc. Generally, I get enough heat to where I'm almost but not quite burning through the material and then I back off just a bit. My power supply also has a separate setting for a hotter or colder weld which helps for fine tuning or changing positions without having to change the weld parameters.

jota
04-29-2006, 01:21 PM
rufas,many years ago whilst traveling the country installing animal feed systems on farms and building grain hoppers,i had the opportunity to try a mig welder we had done mostly all our work with stick welders.i was also told the setting method you describe basicly the machine recomendations and experience guide you for the first setting,the wire speed can be set as you say on a test work piece not the job! the sound i liken to an egg frying!.you can turn your head back look away and squeeze trigger then adjust for sound or do it with an assistant you weld him/her adjust wire speed up or down.you wont be able to do this on thin gauge sheet steel where you will need to carefully stitch together your work piece to avoid burn through.

BillC
04-29-2006, 10:36 PM
The basic concept of setting up a GMAW machine is to create an equilibrium condition where wire burns off at the same constant rate at which it feeds. At equilibrium there is no burnback and no stubbing into the puddle. Unfortunately, there are an infinite number of combinations of voltage and WFS (current) that provide for that equilibrium. The trick is to find the combination of voltage and WFS that also provide enough energy input into the base metal to produce a weld of the correct profile and fusion.

In other words, the perfect "sizzling" sound only means that you have found an equilibrium burnoff condition. It doesn't mean that you have the correct setting for the material thickness you are welding.

Tapped transformer machines should not be adjusted under load. It is common practice to set the voltage for the material size, then fine tune the current (WFS) under load until the optimal burnoff rate is achieved. The correct voltage or current can be found in tables. The Miller MIG calculator is also a good reference that I have found to provide a great starting point.

Regards,

Dan
04-29-2006, 10:49 PM
The basic concept of setting up a GMAW machine is to create an equilibrium condition where wire burns off at the same constant rate at which it feeds. At equilibrium there is no burnback and no stubbing into the puddle. Unfortunately, there are an infinite number of combinations of voltage and WFS (current) that provide for that equilibrium. The trick is to find the combination of voltage and WFS that also provide enough energy input into the base metal to produce a weld of the correct profile and fusion.

In other words, the perfect "sizzling" sound only means that you have found an equilibrium burnoff condition. It doesn't mean that you have the correct setting for the material thickness you are welding.

Tapped transformer machines should not be adjusted under load. It is common practice to set the voltage for the material size, then fine tune the current (WFS) under load until the optimal burnoff rate is achieved. The correct voltage or current can be found in tables. The Miller MIG calculator is also a good reference that I have found to provide a great starting point.

Regards,

Excellent post Bill.

Sundown
05-01-2006, 08:00 AM
The basic concept of setting up a GMAW machine is to create an equilibrium condition where wire burns off at the same constant rate at which it feeds. At equilibrium there is no burnback and no stubbing into the puddle. Unfortunately, there are an infinite number of combinations of voltage and WFS (current) that provide for that equilibrium. The trick is to find the combination of voltage and WFS that also provide enough energy input into the base metal to produce a weld of the correct profile and fusion.

In other words, the perfect "sizzling" sound only means that you have found an equilibrium burnoff condition. It doesn't mean that you have the correct setting for the material thickness you are welding.

Tapped transformer machines should not be adjusted under load. It is common practice to set the voltage for the material size, then fine tune the current (WFS) under load until the optimal burnoff rate is achieved. The correct voltage or current can be found in tables. The Miller MIG calculator is also a good reference that I have found to provide a great starting point.

Regards,

Ah yes, the devil is in the details, clear and concise ... very nicely put. :)

lgjhn
05-02-2006, 10:10 PM
I just watched a TV show "V8TV" where HTP gave a newbie first MIG lessons. Here's what he said. To paraphrase;

Welding 1/8" or so medium steel, solid wire/gas.
To set wire speed hold the gun with the nozzle in contact with a test piece of steel similar to the work piece at an angle ~45deg. and pull the trigger and without moving the gun adjust the wire speed for proper sound. (no popping due to insufficient or excessive wire feed) Sort of somewhere in the middle of the two.
The proper wire speed is when you get the magical sizzling sound.

I understand what he was describing, but he failed to talk about how to establish proper voltage setting, I would think the voltage setting would be selected first then adjust the wire speed. Am I correct in thinking voltage setting is determined by work thickness?

I need to do a lot of sheetmetal repairs, blow through is a big issue. If I select the voltage properly (not sure how I do that other than thickness charts) is the process for setting wire speed vaild, just using short pulses to keep the work from getting too hot?

I know trial, error and practice is the way to learn it but sometimes I feel I'm spinning my wheels. (and running out of coupons)

Set me straight on this blather...

Rufus, stay away from those TV shows......:p Next thing ya know you'll think you're Jesse James or something....
Not sure what kind of sheetmetal work you're doing, but I do alot of automotive sheetmetal and use a MM210 for it...turned way down of course. In order to avoid heat distortion, warping etc., I do NOT try to weld sheetmetal by running stringers...even short ones. Instead, I use a series of small tack welds alternating from one side to the other to other side of the work to give the metal a chance to cool. Keep filling in with tacks till you get it all pretty much filled in. Grind and fill in any left over spots. It can be slow boring work, but you'll not have any heat distortion.

rufus
05-03-2006, 07:38 PM
The tack process is what I use for sheet, I understand all the reasons. I found out the idea that the TV show was describing is actually very old. I did a little research and found a book (quite old) that actually suggested the same proceedure for setting speed. That's what the root question was . Even using the tack process you do need to have the speed set appropriately. You are correct, continuous beads are sure to warp or worse.

Thanks for the comments...