Thread: Chinese MIG Spool Gun Problems

hey guys starting a new thread, as discussed in my other removed thread i mentioned i was going to try a chinese mig spool gun converter its a basic mig spol gun with a little power pack that does some type of power converting to run off a inverter MMA/stick welder, im using my chinese mishto TIG/MMA machine to power this converter spool gun and i have done some testing
karl mentioned im getting burnback from too little wire feed speed now i measured 90cm worth and it took 17 seconds to feed from the gun, the spool gun only has 1 V drive roll with two sizes .6 and .8mm i was sold the only aluminium wire in stock which was .9mm and all that seems to be happening is burnback and melting the tip, what im getting on the work pieces is blobs/balls of melting aluminum covered in black stuff
i thought it might have been a faulty gas solenoid untill i spoke to karl thanks mate, is there anyway i can increase the wire feed speed or could my problem be on the TIG/MMA machine i only have it set to around 100-120amps and the mig converter might need maximum amps to operate?

this is a sample model the mig spool gun converter arrived broken around the gas outlet

Originally Posted by gazza2009au

i only have it set to around 100-120amps and the mig converter might need maximum amps to operate?

Does the "user manual" printed on the top of the unit say anything about how the supply welder should be set?

I know you have a completely different setup but just to give to a comparo
Running my MIG just now on a bit of 3mm plate getting a decent weld.
The readings were just using straight MIG, no pulse using 1.2mm wire:
15 volts
79 amps
5.0 metres/min

So going by that you possibly need to increase your wire speed and decrease your power supply output.

Hard to know what settings you will need as you are also using smaller 0.9 wire.

MIG usually works between constant voltage setting and wire speed to determine the welding current and your power supply is setup as constant current making it hard to compare settings.

It will just be a bit of trial and error I think but try setting around 80 amps and up the wire speed considerably. Try to have the wire curling up away from the weld keeping about 20mm stick out, use a pushing action and if running right should not be burning back but making a hissing sound.

If it is still burning back check the gun is feeding smoothly and solidly and keep increasing the wire speed while maintaining or dropping the current.

Burn back is usually from too slow a wire speed or insufficient stick out or both. Other things like feed problems also

hey rusty, thats just instructions on how to connect it pretty basic really, i just done some testing on the wire speed

.8mm drive roll, .8mm gasless wire fed 90cm length in 7-8 seconds timed with iphone stop watch
.8mm drive roll, .9mm aluminium wire fed 90cm length in 8 seconds

according to the miller calculator/web site using .9mm wire i should be using a wire feed speed of 889-1016cm per minute

my wire feed speed is only 675cm per minute

Miller - MIG Welding Calculator

what a flop waste of $150

Originally Posted by johncar

I know you have a completely different setup but just to give to a comparo
Running my MIG just now on a bit of 3mm plate getting a decent weld.
The readings were just using straight MIG, no pulse using 1.2mm wire:
15 volts
79 amps
5.0 metres/min

So going by that you possibly need to increase your wire speed and decrease your power supply output.

Hard to know what settings you will need as you are also using smaller 0.9 wire.

MIG usually works between constant voltage setting and wire speed to determine the welding current and your power supply is setup as constant current making it hard to compare settings.

It will just be a bit of trial and error I think but try setting around 80 amps and up the wire speed considerably. Try to have the wire curling up away from the weld keeping about 20mm stick out, use a pushing action and if running right should not be burning back but making a hissing sound.

If it is still burning back check the gun is feeding smoothly and solidly and keep increasing the wire speed while maintaining or dropping the current.

Burn back is usually from too slow a wire speed or insufficient stick out or both. Other things like feed problems also

thanks john, i have the wire feed speed set at maximum and im still getting the burnback i think its just a poor design i just listed this spool gun on ebay i have no further use for it i will look for a mig that can aluminium weld to use as a back up if my TIG machine fails half way thru a job

I was very disappointed with the performance of my Lincoln 180C with spool gun set up and it cost me around the $1400 dollar mark!!
Found it hit and miss with set up and still had feed problems with the .9mm wire.
Rollers on the Lincoln spool gun also were a v type.
The little Lincoln works great for steel but not the best machine for ally.

Ended up pushing it aside and spending the big dollars for a machine that is 10 x easier to use and with quality results.
Ive tried the synergic values on the new machine with normal mig on 3mm plate and didn't like it as much as pulse. Still was heaps better then the Lincoln. Settings were 140amps with a 8.8 wfs.

Then tried same material with synergic pulse at 91amps and 5.6 wfs.
The big decrease in heat made it a lot easier for me to do the same job with much better results.

1.2mm would be the minimum wire size Id use for aluminium. Anything less and your asking for trouble.

there is one thing i thought of today while testing this spool gun which is inside of the gun between the aluminium spool and drive roll is a nylon tube but up the front of the torch from the drive roll to the tip of the gun looks to be the same spiral metal tube used on mig welders for steel do u think this could be the problem? without the wire inserted thru the gun the electric motor has a much higher RPM, i tried sticking my finger on the drive roll and pressed the trigger it had some grunt

Try poking your .9mm wire through the liner to see how much drag there is. The Lincoln gun also has a steel liner up front, shouldn't cause a problem over that length.

Originally Posted by cwcarter

I was very disappointed with the performance of my Lincoln 180C with spool gun set up and it cost me around the $1400 dollar mark!!
Found it hit and miss with set up and still had feed problems with the .9mm wire.
Rollers on the Lincoln spool gun also were a v type.
The little Lincoln works great for steel but not the best machine for ally.

Ended up pushing it aside and spending the big dollars for a machine that is 10 x easier to use and with quality results.
Ive tried the synergic values on the new machine with normal mig on 3mm plate and didn't like it as much as pulse. Still was heaps better then the Lincoln. Settings were 140amps with a 8.8 wfs.

Then tried same material with synergic pulse at 91amps and 5.6 wfs.
The big decrease in heat made it a lot easier for me to do the same job with much better results.

1.2mm would be the minimum wire size Id use for aluminium. Anything less and your asking for trouble.

Do you know what your voltage setting was? I must admit that I was trialing mine on basic MIG so I could independently set the wire speed and voltage. Anything above 5.5 wfs and 15 volts about 80 amps I was melting holes in 3mm plate at the end of a 40mm stitch or maybe I was travelling too slow, but at the settings above I was able to do a decent enough weld. Bead was sitting a little higher than with pulse.

I will play around with the synergic settings tomorrow and see what happens but synergic pulse and double pulse is addictively easy by comparison I agree.

Spool guns must work OK as there are plenty around but I think that like everything with welding ally things need to be optimum to be able to tweak it just right. Most machines that take a spool gun seem to have an additional board to drive the thing and I don't know what that entails but the machine has to be spool gun compatible basically.
Not to say that some sort of converter is possible and there may be a way to get it to work even be it a bit touchy. Worth giving it a try though with not a big outlay. It's all a bit of fun.

Originally Posted by cwcarter

Try poking your .9mm wire through the liner to see how much drag there is. The Lincoln gun also has a steel liner up front, shouldn't cause a problem over that length.

cheers carter, i just tested that and it has 75grams of pulling friction on my digital scales


i just pulled the spool gun semi apart and went over everything, the steel liner was going past the 4 gas flow holes in the tip holder and some of the outer steel liner coating was melted inside of the tip holder so i removed the melted plastic and cut back the steel liner so it ends just before the 4 gas holes in the tip holder

i than greased the wire spool shaft and i left the spool gun cover open and also left the drive wheel cover off so i could minimize everything stopping the feeding i set the welder to 110amps and it welded YAY not the best and way to much heat but non the less it didnt burnback

heres a picture of the messy weld and inside the 40x40x3mm tubing showing the penetration

my pics are not uploading now for some reason so ive uploaded them to photobucket there was a lot of spatter i forgot to mention

Now you see why I have always advised against spool guns, just another variable to cause trouble.
I would suggest that your converter is probably best utilised as a paperweight. As I mentioned earlier, I have used a voltage sensing wire feed unit before and while it did the job, it was not in the same league as a mig.
I think you are on the right track with purchasing a mig that will run 1.2 ally wire. Buy a decent one, preferably with a separate wirefeed unit.
Honestly, I beleve that the spoolgun unit you bought was at best a compromise that was of more benefit to the vendor than the customer.
You win some, you lose some.

John, pretty sure you must be over the 22 volt mark to be in spray transfer for aluminium. Miller has good calculators. In any case I find normal spray transfer to hot for 3mm ally. Must move very quick.

My synergic values don't show voltage settings as it is. Pretty sure I read somewhere that I can view it though. I'll check it out tomorrow.

Gazza was thinking the liner is made to fit only .8mm wire?

Yeah I thought so too re the volts. I initially set it at 20 volts and it just blew a hole virtually straight through the 3mm. May have been ok on some 6mm.
I just kept winding it back until it came under control and to my surprise it was showing 15.1volts on the display. It sounded more like short circuit transfer though as you would expect but it was welding OK with a fairly clean result.
Anyway I will mess with it a bit more and see for sure what is going on and see if I can get some better results at 20+ volts. pretty sure on synergic pulse it was running at around 17 volts for 2.5mm at 5.5 wfs which was slightly hot.


I was just trying to get some current vs wire speed as an indicator as to where gazza may need to be with the spool gun and assuming that .9mm wire would have to run considerably faster than 1.2mm

Most of my settings when I built the mig cart were around 94-116 amps with 5.7-7.1 wfs depending on joint using pulse and d/pulse.
These settings were for material thickness between 3.1 -3.6mm. Shall have to find the voltage settings for a better comparison.