Like most tools and equipment, you get what you pay for. Better quality welder can be expected to do a better job.

Same applies to the gasless flux-cored welding wire you use. Better more expensive wire gives a better weld. This applies to stick welder rods too. Get the good brand names.

Robin

A good inverter MMA welder will go down to 1 mm or a bit less with a decent small rod and a steady hand. Needs some practice and the self control to keep the welds short so as not to overheat the metal before the arc joins it. Tack together first then extend. If you go too long the metal suddenly disappears at an amazing rate!

Mine is an older industrial standard Fronius Transpocket which does a good job of kidding folk that I can actually weld! As I understand it the affordable breed have pretty much caught up in capability.

With lower cost MIG the main issue is wire feed drive and weld current stability. Gassless being much more demanding on both than plain wire. Back in the day affordable SIP won an unenviable reputation for being less than good at both whilst the Clarke wire feed system was justly considered very effective. Reliable wire feed gives the power supply a much easier ride.

I tried MIG a time or two with basic boxes and got nowhere fast. Finally picked up an ESAB synergic at a £££ very reasonable and am now doing just fine. Although MMA habits still sometimes creep in. Am convinced that the lower end MIG work just fine for someone who can do MIG but if things don't click quite quickly a neophyte is basically stuffed.

If you do go MIG best to bite the bullet, get a half decent one and proper gas. Mine came with the Air Liquide Albee cylinder so I didn't need to get a regulator.

Clive

Clive has it ! I've had mig for almost 50 years and MMA for longer. I have 2 cheap MIGs both given to me and though I have reasonable skill I cannot get what I would call good welds from either. There is no such thing as GASLESS MIG ! It is MMA with the filler rod on a reel. If you want to avoid gas rent Etc then speak to a publican about a bottler of Co2, now your in the realms of MAG. A good MMA machine and 1.6 rods should do your job with a bit of practice, turning the power down if blowing holes is often the wrong move, it may need turning UP.

Using a toy car motor for wire feed was never going to work well though that's what some used. IF you can find a BOC AUTOLYNX buy it, you will have one of the best 160A migs ever made. Good luck Noel.

Plenty of stuff on youtube about welding thin materials

The only "easy" route seems to be a good TIG unit with a bottle

Any other cheapy route will need a lot of practice and experimentation, I tried with stick for quite a while and the level of concentration needed was too much for an old guy, and there were just too many variables

I haven't tried thin sheets with gasless MIG yet but if you do get one get a decent unit for a nice steady arc, I dumped my £100 lidl unit and got a Vevor type one for 200+, the electrics are far better and the welding much easier, a better machine will always give you a better chance of doing a decent job

Youtube is your pal here, spend an evening filtering through the garbage to find the more useful videos

Edited By Ady1 on 28/03/2022 10:13:44

The main advantage of MIG for me is that when I mess up and blow a hole I can pulse the trigger and blob enough weld in to fill it up and then try again. Never got the hang of doing this with arc, have been trying to learn TIG but have probably left it too late as dexterity and eyesight aren't up to it, and it's slow going compared to the others.

I use a SIP unit bought in late eighties, looks very similar to Clarke units still sold by Machine Mart & others now. I have had refillable bottles in the past when doing car work but for odd jobs now the disposables are OK, note there are different fill capacities for the same size bottle (390g vs 600g) so read description carefully before buying.

Glad to have been of service Robin! The reason the increase of amps works if holes appear IS ! There are 2 reasons holes may appear in thin material, A, The current is way to high – obvious ! the second is the current is to low, you dwell on the spot to get the metal to flow, way to long and plop – it's gone ! Increasing the current to the right value will cause almost instant joining (flow) and your away – more heat but for less time at that spot. Good luck. Noel.

A copper heatsink, behind thin metals, is a good ploy to avoid blowing holes quite so quickly.

"she's a psychologist for some reason "

That has to be quote of the day …

pgk

I think the thing about a good inverter welder is that they clamp the current almost instantaneously once the arc is struck. An old style transformer welder inherently controls the voltage rather than the current so by altering the arc length you have some manual control over the actual weld current and heat input. The AC output helps as the continual voltage cycling between zero and peak reduces the average heating input but still has a decent peak to make the weld. Sort of like an uber fast preheat – weld cycle I guess.

With a DC inverter what you set is what you get. If you set a bit too much it rapidly burns through due tothe continuous heat input. Strike voltage is generally higher so arc starting can be more reliable but breaking the arc harder. My Fronius needs a very quick pull back to break the arc. If you want to play silly games on higher current settings a slow, careful pull back can stretch the arc to 6 or 8 inches long before it breaks!

Good Inverter welders can work with a very short arc length. Which helps on thinner materials as the ent heat input is less. With the right balance of current and metal thickness its possible to make good welds between well prepped edges by simply dragging the rod own the joint with a little side to side movement. Handy on vertical welds. But a trick I've not yet mastered. About 50/50 good/crap ratio. The good ones are amazingly clean joins.

John is absolutely right to say that the art is getting a sufficiently capable machine able to do relaible work without too much operator compensation. The usual price performance ratio.There is only so much capability you can pack into a lower cost machine so the operator generall has to work harder. Which makes life difficult for neophytes.

Clive

I've joined quite a lot of thin steel assemblies over the last few years, mostly SHS with wall thickness around 1.2mm but also some sheet down to 0.8mm using a plain inverter MMA welder and 2mm rods. Like others have said, the trick is plenty of current and short 'stitching' beads all linked together. Too much time spent in the one spot will certainly blow a hole, but these are repairable. Sometimes i stick the bare end of another rod into the hole and weld over it, other times a spare scrap of metal from the waste bin, even ordinary nails are useful for this. Like other skills it takes time and practice to reach any level of proficiency, and a touch with the angle grinder afterwards hides most mistakes.