[glivo]

I found this page and read it, watched the video and understand the underlying principle.
http://www.weldingtipsandtricks.com/mig ... ics-3.html
Setting wire speed and voltage without a chart.

My question is simple. My old welder (now dead) and at least one other I have in the shed now, do not have independent wire feed and voltage controls. In other words the minimum and maximum wire feed rates, and all in between, are not the same when different voltage selections are made.

This means that if I were to set the feed rate to 250"/min in one voltage setting, when I change to a different voltage the feed rate would also change. Am I missing something?

I'm going to have to go and play with my welders and measure now.

[weldin mike 27]

Hi there,

I know what you, but I think we might be thinking different ends of the spectrum. Could you please send or post a photo of the machine so we can get an idea of the controls? Thanks, mick. Ps, I'm from Australia as well.

[Poland308]

Think the best way to get a good answer might be to post up a picture of the front of your machine. Not sure if I’ve ever seen a mig machine without two adjustments. One for voltage the other for feed speed. While some machines have infinite adjustment some are just a set range.

[glivo]

I don't have a photo of the old one but it was a Cigweld Transmig 130 Twin. The one I have now that I believe operates the same way is a Toolex 140N Dual Purpose.
They both have voltage controls and wire speed control.
The 130 Twin had 4 voltage settings controlled by 2 switches, MAX / MIN and 1 / 2.
The Toolex has 6 voltage settings controlled by 3 switches, High / Low, MAX / | and MED / MIN .
They both have a wire speed adjustment dial from 0 - 10.

What I'm saying is that if I set the wire speed to say Mk 3/10 and just leave it alone (as per the video), I will get different rates of wire speed by changing just the voltage settings. So leaving the wire feed on 3, as suggested in the video, the wire will feed through at different rates dependent upon the voltage switch positions. Lower voltage means slower feed, higher voltage means faster speed. Without touching the wire speed dial the feed rate changes when you change the voltage.

The wire feed rate and voltage are not independent controls. They are in fact interdependent. The output from the voltage selection switches and the wire feed dial are both fed into the PCB which controls the pulse modulated DC current that drives the wire feed motor. Both of these settings determine the rate of feed.

This makes the video method not possible. Well it is possible but not as easy as it is made out to be.

[Coldman]

Here is a pic of the Toolex:

Toolex.jpg (60.74 KiB) Viewed 3395 times

The method Jody describes works very well for mig machines.

If this is the machine you have, here is the bad news, this toolex is not a mig machine, it's a piece of junk masquerading as something useful, IMO of course. One went at auction for $75 recently, I think they paid too much, and it looked new.

Don't waste your time with it, sell it, dump it, just get rid of it and get something decent.

[glivo]

Toolex Turbo 140N Dual Purpose Mig Welder.
This is what the instruction manual says about Voltage setting.
"The machine depending on the model will have 2, 4 or 6 output settings, controlled by rocker switches on the front panel." (Mine has 6 voltage output settings controlled by 3 rocker switches.)
"Switching from one setting to the other automatically increases and decreases the wire speed and therefore the welding output."
(I'm assuming this means the welding output current as a set voltage has been selected using the switches.)
"N.B. The wire feed speed is automatically adjusted when the output is selected. The wire speed setting control provides fine tuning."
(My observations show that this fine tuning is not so fine. It is continuously variable but it spans a pretty wide range.) #1

Test results.
For each test the wire speed is set and not touched. Only voltage settings changed. As per the video and instructions.

1) Wire speed on SLOW (minimum)
Voltage Range set to LOW
Voltage adjustment MIN 95"/min
MED 130"/min
MAX 180"/min
Voltage Range set to HIGH
Voltage adjustment MIN 260"/min
MED 340"/min
MAX 450"/min

2) Wire speed set to 12 o'clock (middle)
Voltage Range set to LOW
Voltage adjustment MIN 240"/min
MED 290"/min
MAX 330"/min
Voltage Range set to HIGH
Voltage adjustment MIN 420"/min
MED 460"/min
MAX 620"/min

3) Wire speed set to FAST (maximum)
Voltage Range set to LOW
Voltage adjustment MIN 490"/min
MED 530"/min
MAX 640"/min
Voltage Range set to HIGH
Voltage adjustment MIN 730"/min
MED 790"/min
MAX 850"/min

Conclusion:
These results show that for this welder the suggested method, as demonstrated in the video will not work. I do now however have the required data to set the welder as per the suggested equations.

#1 These results can be read in reverse.
On the same voltage setting of Range LOW/MIN the wire feed adjustment will control from speeds of 95"/min up to 490"/min.
On voltage setting HIGH/MAX wire feed adjustment will vary from 450"/min up to 850"/min

[glivo]

Here is a pic of the Toolex:

Toolex.jpg

The method Jody describes works very well for mig machines.

If this is the machine you have, here is the bad news, this toolex is not a mig machine, it's a piece of junk masquerading as something useful, IMO of course. One went at auction for $75 recently, I think they paid too much, and it looked new.

Don't waste your time with it, sell it, dump it, just get rid of it and get something decent.

I already have other machines. I'm just saying that the method demonstrated and explained will not work for machines that have interdependent wire speed and voltage controls, which is actually many smaller MIG welders. My old Cigwled operated the same way and I intend on testing the Unimig and both Cigwelds I have to see if they behave in the same way.

I picked this one up for a lot less than $75. Only bidder in a $0.99 auction. I guess that says something though.

[Coldman]

Well it's difficult to buy anything for 99cents anymore so I recon you got a bargain. My guess is that after you get tired of the poor performance of this box, given you have other better machines, it's gonna be gathering dust in a corner somewhere. I recon cash converters will give you $20 if you ask for $60. Good profit and time saving all in one.

[glivo]

It is all but new even though it is 8 years old. The guy I got it from couldn't get it to weld gasless (neither could I when I got it home) so he gave it away with a welding helmet some oxy goggles and a couple of small rolls of gas wire. I couldn't work out what was wrong when I tried it at first then twigged he had the polarity wrong way round for gasless. I swapped it over but still no joy. Thinking I'd bought a dud I had a closer look and the silly bugger had put a roll of 316 in it. I swapped it over for gasless wire and away she went.

These things came with a silly little 4 mm gas tube out the back and only a tiny push to connect regulator for disposable bottles, which I got with it. Handy to have I suppose and they cost near $30 alone. I'm waiting on some fitting to arrive to convert it to proper gas supply. I'll probably get it going so I can demonstrate it welding and flog it off.

The other thing about it is it uses tiny little 5 mm tips and Gasweld (the main seller of Toolex brand) don't stock them any more. That's helpful!! They are available online so I also have some of those now otherwise you'd be lookin' at swapping out the hard connected torch. I'd hazard to guess the one in it was the first one ever used.

[glivo]

Back on topic:
I just tested 2 other Mig welders and I'm not too surprised that both of these are also giving variable wire feed measurements based solely upon voltage adjustment with the wire feed set and left. Admittedly, and for the most part, they are nowhere near as wildly variable as the Toolex but it still begs the question of does this method work.

(It also raises concern that one of the welders has a dodgy wire feed mechanism.)

The Unimig MIG180 has 6 voltage settings. Tested on wire feed settings of Minimum, 3/10, 6/10 and 10/10 the variations of feed rate, caused by changing voltage alone over the 6 settings, were 60"/min, 80"/min, 110"/min and 120"/min respectively.
ie: not constant.

The Cigweld 150 was a bit odd in as much as slow wire feed settings just didn't want to produce smooth feed at all. Jumpy and jerky from the get go up to about 5/10. Above that the roller spun up smooth. I'd say it would be difficult to weld at slow speed with this machine and maybe the wire feed unit is damaged or worn from excessive wire pressure on the rollers.

Anyway it has 4 voltage settings and at low speeds of minimum and 3/10 the voltage changes caused variations of only 40"/min. These being 75"/min to 115"/min and 90"/min to 130"/min respectively. At speed setting 6/10 the 4 voltage settings caused very little variation in wire feed. Only 30"/min from 130 to 160. However at maximum speed 10/10 the voltage change caused massive wire feed variation similar to the Toolex. Variation of 350"/min from 410 to 760.

No matter which way I look at it I can't see this method working on any of these 3 welders.

Edit: Forgot to mention I couldn't measure the 175i+. Being digital inverter etc or whatever, the wire feed appeared to be electronically variable trying to search for and /or maintain an arc, which wasn't there. On really low speed it first fed quickly then slowed down. On slightly higher speed it came out slow then sped up. I'm not sure about that but someone with more knowledge than me might be able to explain it. I still haven't created a spark with it yet. Maybe tomorrow.

[glivo]

Feed rate chart created from measurement testing wire feed rates.

Extrapolated feed rates

Toolex in per min.png (32.15 KiB) Viewed 3383 times

From this it should be possible to use Jody's tables and multiplication factors to set this welder. From the video assuming we need a wire feed rate of approximately 250 in/minute you could select one of 4 settings (shown in green) to find which one gives the best result and then fine tune the wire feed from there.

I'll give it a go tomorrow.

[glivo]

I did quickly try it out on the crappy Toolex welder yesterday and the result was that I had to use the highest voltage / lowest wire feed setting suggested by the table. Dropping the voltage back and upping the feed just didn't like it at all. I had some 2.75mm / 0.110" material and using 0.8 / 0.030 wire, so I was aiming at feeds around the 220 ipm mark from the calculation, which gave me the 195 / 210 / 220. Only the 220 at the higher voltage went near a weld. I think going up to the next voltage and winding the wire back to minimum (260) might have been better than going down and staying close to the calculated mark.

I've prepped some steel to test the other welders but ran out of time. I'll get to it eventually.

I notice in Basic Mig part 5 that the Hobart welder appears to have independent wire feed rate controls. Jody has marked the ipm rates inside the cover and is certain of the selected speed irrespective of voltage. This is definitely not what I found with 3 of 3 welders I measured.

Question: This was done using FCAW as I haven't converted the welder to accept industry gas connection yet. Does that make a difference to the calculations?

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[Poland308]

The respective speeds for fluxcore wire compared to solid core wire of the same diameter will differ to get a good weld. However 200 Ipm should be 200 despite the wire, as long as it’s the same diameter. Realistically even wire diameter shouldn’t change the wire speed because this variable only affects the size of the grooves in the feed wheels. The resulting welds from different wire compositions or different diameters with equal feed speeds will be different. Simple logic, .030 wire at 200 ipm will require different voltage than .045 wire at the same speed. Also the resulting weld even with corrected voltages but identical feed speeds would have different profiles and deposition rates. Flux core is hollow so 200 ipm would require a different voltage than solid wire of an equal diameter. Deposition rates and weld characteristics would be different as well if all other variables were the same.

[glivo]

Thanks for the reply P308. I understand all of that. 0.030" (0.8mm) solid wire will put down more metal than hollow flux core of the same diameter. I guess I didn't ask the question very well.

The table in Mig Welding Basics Part 3 uses calculation factors of 3.5 " / amp for 0.023" wire, 2" / amp for 0.030" wire, 1.6" / amp for 0.035" wire and 1" / amp for 0.040" wire. I'm assuming that these factors are for solid wire.

So what I'm asking is what would be the wire burn off factor for Flux Core 0.030" wire?

Logic tells me it should be more than 2" / amp but would the metal deposit required be the same as 0.023" for example requiring 3.5" / amp or somewhere in between? I'm just wondering since the use of flux cored wire in my testing of the extrapolated table would be off the mark and give skewed results. A new column may be required to show the calculated feed rates for FCAW.

The whole idea is to create a quick reference table for this welder that has absolutely no recommendation or tables for setting the voltages and speeds. Fluxcore wire would be one thing I'd want in that quick reference table of settings.

[Poland308]

The actual amperage of the mig weld process is directly related to the cross sectional diameter of the wire. There are some older posts that have reference charts that may contain the information you are seeking. I don’t have those charts, but I’m sure some of the others here might have them saved. These same charts might also be found on a manufacturer web site detailing the specific wire your referencing. What brand and kind of flux core wire are you working with?

[glivo]

Thank you for your answers but you are missing the point of my line of questioning.

The welding machine in question has no data, not tables and no real guidelines for settings in the user manual. This is why I looked at this method to determine settings for this particular machine. This scenario is exactly what it's for.

The Welding Tips and Tricks Website "Basic Mig Welding Part 3" page is all about setting a welder to run a good weld without any data. It is based upon the wire feed on a welder completely and solely and without any charts tables or numbers from a book. It is based solely on the thickness of the material to be welded and the diameter of the wire being used. From these 2 numbers a calculation is done to determine the necessary wire feed rate in inches per minute. The appropriate setting is found on the welder by simply measuring the output of wire from the welder and then setting the wire feed to the correct calculated point. Then you leave it alone.

After this is done the range of voltage settings is tested until the weld is running smoothly. The wire feed is not supposed to be moved any more up to this point. There is no mention of, nor need know, the weld current. It is all about finding the weld settings with nothing to go on but the thickness of the material and the wire diameter. Nothing from the wire manufacturer or welder. Just the thickness of the steel to be welded and the size of the wire.

To facilitate this, the calculation is done which involves multiplication factors of 1, 1.6, 2 and 3.5 for the different diameter wires.

Wire feed in inches/minute = Material thickness in thousands of an inch X the multiplication factor for the wire being used.

I had 2 questions.

1) The welders I have here do not have independent wire speed adjustment. The Hobart welder shown in the video from the web pages does. On the welders I have here the output of the wire feed mechanism is affected by a change in the voltage settings. It is not consistent across the full range of voltages. This makes the process for my welders different. Slightly more involved but still achievable by the production of the little table above. So that was my first question and I answered it myself by measuring the wire feed output of all 3 welders across the full range of settings. The welders I have here operate differently to the Hobart machine Jody demonstrates with.

So now I went and tested out my calculated table of settings. This is where question 2 comes from.

2) I used 0.030" (0.8 mm) flux cored wire and when I put the welder on the calculated settings for 0.030" solid wire it didn't provide the desired result. It welded but I think there was something wrong and it is obviously the use of fluxed wire. The calculations don't transfer directly from solid to fluxed wire. My question is about the multiplication factor for flux cored wire. It will be something different to 1, 1.6, 2 and 3.5. I'll probably have to try to work it out for myself. I just though somebody might know.

[Poland308]

In order to calculate the correct multiplier for your flux core wire you will need to know the cross sectional diameter of the wire. This should be available from the manufacturer, and will vary depending on the size of the hollow center of flux core wire. Then you can treat it like a ratio.

[glivo]

So you mean that I'd need to know the outer and inner diameter (sheath thickness) so that I can work out the cross-sectional area of the steel, sheath only? The other thing to do would be to accurately weigh a set lengths of wire for the different wires. If the length of wire were long enough or your scales accurate enough you could get a pretty close ratio.

I found length to weight ratios for a fluxcore and a solid wire but only in 0.045" and in different units.
To standardize I converted to inches per pound: Solid wire is 2260"/lb and Harris Dynashield E71T-1 is 2700"/lb. Approx 4:5.

Applying this ratio to the multiplication factors would give fluxcore factors of 1.25 for 0.045", 2.0 for 0.035" and 2.5 for 0.030". Probably not going to use 0.023" fluxcore but it would be a factor of 4.0. So basically I would just need to bump the calculated solid wire speeds up by 25% to get a rough starting point for fluxcore of the same diameter. Maybe even as much as 50% for smaller diameter / thinner sheath etc.

Either way it does explain why my first test run of this method wasn't what I expected.

[Poland308]

You would still need to know the cross sectional area of the void and the weight of the internal flux to do it by weight.

[glivo]

I agree with you in principle, if this were an exacting procedure and method. However, the original premise is not a precision operation from the outset. Based on the idea of approximately 1amp per thou of material thickness and then a multiplier based on wire diameter gives only a calculated approximate feed rate. The welder feed rates obtained by measurement are subject to some error and slight variation as well. Once the rate is set close to the calculated mark, the range of voltages are trialled until the balanced arc is found. None of this is done to any significant degree of precision. This is, at best, a "ballpark" method of obtaining settings and I would think that at the end of the process, and after doing test welds, the wire feed may then require fine tuning adjustment anyway.

There would probably, or at least possibly, be variation in burnoff rates from one wire manufacturer to the next or even across batches. I think I now have an understanding of the problem I encountered and sufficient information to set this welder up to run based on metal thickness and wire diameter including FCAW. I've now added adjusted columns to my spreedsheat table so I'll put it to the test and see what happens.


EDIT: Just to throw a spanner into the works, in the material thickness range I have been using here, the weld settings guide table inside the cover of the Cigwled 150 MIG shows that the wire feed setting for fluxcore should be slower than for solid wire of the same diameter with the same voltage setting. For very thin material they are suggesting the same settings but above 1.5mm they say that fluxcore should be slower. This is directly opposite to the theory so far.

I suppose the disclaimer is that these are "suggested" settings only and that personal experience and ability will affect the results.


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[Poland308]

Yes the variables are almost endless. Part of another difference is that the flux does affect the weld process. It essentially uses some of the heat of the arc to do its thing. And polarity is reversed during the process most times, but I think some flux core wires I think are designed to run with the same polarity as solid wire. Another question that’s usually easy to research from the manufacturer.

[glivo]

That is assuming you know the manufacturer. Two rolls of wire I have obtained with a welder appear to be "generically" labelled. I'll have to take a closer look. I can't say I've ever used, or even seen, standard polarity fluxcore wire, even though I've heard of its existence.

A strange thing happened yesterday. I was running sample / practice welds on my different welders, to test this method of setting up, using 0.030" fluxcore wire. Fillet welds, 4" long on material 0.110" thick. I was using a magnetic support to hold the pieces in position and firm on the table.

When I used the Cigweld 150 Mig, for about 1" the weld wire refused to push into the corner, instead laying separate beads along the surface of each piece with no connection or penetration. Confused at first (mask down), I then realized it was coinciding with the position of the magnetic support. I scratched my head, removed it ( the magnet, not my head) and held the now already joined at each end pieces in the vice, ground it back out, and I was able to weld over that section without issue.

The odd thing is that I did not have the same thing happen with the other 3 welders. They welded continuously from end to end directly over and past the magnet, no problem. Has anybody else ever had magnetic supports interfere with weld deposit and penetration? Why would it affect only this welder?

I'm going to keep playing around with the different welders just for practice and experimentation. I'm finding they behave and weld quite differently and out of the 3 second hand machines, I'd say at this point I really like using the Unimig 180, followed by the Toolex 140N and then surprisingly last, the Cigweld 150. I've ordered a new wire feed assembly for it as it just won't feed properly at the low end.

The happy news is I also struck an arc on the new welder, (4 weeks after buying it) using solid wire and gas. Very nice to use and I made a good weld straight up so I'm pretty pleased with it. I'm now looking forward to teaching myself how to Tig weld on it, albeit only Lift DC. I've got the matched 17 gun here and a 9 arriving today, Coldman has sent me his pedal which I'll need to modify. Now I just need to find some time.

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[Poland308]

Yes magnets and magnetism can interfere with the arc. This will affect stick and tig as well.

[ljdm1956]

Never tried it with Tig, after finding out how magnets affect my Mig arc. If you use a 90deg magnet to hold pcs together, etc, try and tack as far from the magnet as possible.

[glivo]

That's what I was using.
I can see why it would now thinking about it. Droplets of liquid magnetic material floating around in a magnetic field. Doh!!! But unusual that it really only seemed to affect the weld of 1 out of 3 welders. Or at least it really gave that one a nudge where the other 2 (3 if you count the new one) welded right over it. Maybe something to do with the suspicious / dodgy wire feed???

Now that I think about it, it was harder to maintain even weld distribution with the other welders over the magnet but nothing like the Cigweld.