# Arc or Mig welding, very confusing!



## lastminute (12 Sep 2020)

I want to do a spot of welding, total beginner...Mig looks the easiest, also confusing is "Inverter"...Flux cored, so any tips/guidance etc. will be most welcome.

Gerry


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## TheTiddles (12 Sep 2020)

What are you wanting to weld? Simple question, kinda important!

Welcome on board 

Aidan


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## lastminute (12 Sep 2020)

Hi Aidan...I want to alter the size of a metal garden gate plus various smaller jobs!
Generally I use nuts n bolts when joining metals and have wanted a welder for some time, just not sure which type would suit.
Tried the Arc type long time ago... didn't take to it... the Mig looks like it might suit me!

Gerry


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## TheTiddles (12 Sep 2020)

Mild steel then, you could go either way.
Aidan


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## Ttrees (12 Sep 2020)

I suggest a used arc welder for steel plate like for what it sounds like you're wanting to do...something like anything past 3 or 4mm steel.
Although it could be a tubular gate of light gauge 2mm steel for all I know.
Not un-doable for an ark, but for sheet metal like van repairs, not suitable.
Steve Bleile videos are regarded as the best.


Depending on your supply might make a difference to your choice.

I suggest around the 180 amp models which look like they have a cooling fan.
I can't clarify on this

I have Lidl's cheapest one that has a thermal cut out,
and a 240 amp which needs 16 amp.

I see the 180 amp models all the time for around 50 that might need a tiny bit of panel beating back to a square shape and paint to spruce up.

New glass for the shield is about 2 quid, a new electrode holder or clamp costs less than a fiver at the co-op, where one might be going anyway to buy the cheapest welding rods at around a tenner for a pack.
A bench grinder to sharpen a pack of long masonry nails that you might get
in the co-op.
A 4" angle grinder, discs, and a wee tack hammer is all you need to be setup.

Tom


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## NickWelford (13 Sep 2020)

Ttrees said:


> A bench grinder to sharpen a pack of long masonry nails that you might get
> in the co-op.
> Tom



what are the masonry nails for?


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## Oddbod70 (13 Sep 2020)

as Aiden says it depends what you want to weld. I mainly do thicker stuff (over 2mm) for which arc is well suited. My arc welder can also do tig, which is for the thinner stuff. I found arc quite easy, but tig needed three hands! At least for me! I got there in the end but it took a while.

whatever you go for keep practising. It takes a while to “click”, but it will....eventually. There is a excellent migweldersforum whics is great for advice.


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## cammy9r (13 Sep 2020)

Hi, If you go the mig route you will find it much easier than arc. However arc is far more useful as it has its own gas shielding (flux around the rod) and lots of choices of rods/flux for different situations. I always found arc to be tricky.
I do mig tig and oxy/acetylene welding, arc if required.
The mig is definitely the easiest but still not as simple as pulling the trigger. As for machines, there are loads out there to suit all budgets and they will all stick metal together. Pop over to this forum MIG Welding Forum
As for jargon, inverter is the type of gubbins inside the machine that gets the electrons flowing. They work really well and are a lot lighter and smaller than the transformer version like for like. Flux core is the wire used when there is no shielding gas available. It is also good for outdoor welding as it makes its own shielding environment on arc.
If you go with the mig and want gas there are 3 ways I know to get it, you choose the cheapest for yourself. Disposable bottles, hobby bottles which are rent free with a deposit on them and rented bottles from one of the bigger suppliers. At home i use the hobbyweld rent free option as i need both pure argon for tig and argon mix for mig. Just remembered the 4th option 'pub gas' co2 is used by many hobby mig welders.
Tig welding is another option. A dc tig will weld many different metals and allow brazing of many too. You will need a dc/ac tig if you ever wander down the aluminium welding path.
With whatever you choose dont go less than 150amps if you plan on going 4-5mm thick.
Edit: many 130-150A might claim to be able to do 6mm. even 5mm can be a push for them in one pass. On thicker steel a 'v' is cut into the edge and a root weld placed followed by a cap weld. I have done 8mm with a 150A using 4 passes so it can be done.


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## hawkeyefxr (13 Sep 2020)

Like to add my little bit here, 
Mig is by far the easiest to use, it will do just about any metal work job you need for use at home..
Tig welding is for me very satisfying, you get the finish of half circles that look very neat.
Arc (stick) welding takes some getting used to as beginners find the rod sticks as they have not learnt 'how to'.
All welding gives you a sense of achievement, you have joined to pieces of metal together for good.
Thickness does not mean much to me as i had years of plate welding, up to 4in (100mm) thick but 3/4 and 1inch were the norm along with stainless, Ali, Copper. All of that was positional as well as we made furnaces for melting steel that weighed up to 25 tons.
I still like welding to this day.
Always wear as darker shield as you can. If you do Ali tig welding be careful of extreme sun burn.


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## TheTiddles (13 Sep 2020)

hawkeyefxr said:


> Like to add my little bit here,
> Mig is by far the easiest to use, it will do just about any metal work job you need for use at home..
> Tig welding is for me very satisfying, you get the finish of half circles that look very neat.
> Arc (stick) welding takes some getting used to as beginners find the rod sticks as they have not learnt 'how to'.
> ...


Good advice, I burned the logo on my t-shirt onto my chest once

Aidan


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## Ttrees (13 Sep 2020)

NickWelford said:


> what are the masonry nails for?


Long picks are good if you want to strengthen or tidy the edge of a weld.
Its very important that one does not try to weld on top of any slag whatsoever.
This can be after one grinds away a bad weld or do something awkward, or tidy up for show surfaces to make an invisible joint.
You could go fancy and make a handle for one nail, and have it sharper than 
the other 7 or 8 you might do at one time, for hitting with the wee hammer.

Close your mouth and wear glasses (as you should be wearing under your shield/mask!)
Hot slag can go anywhere.
Hitting masonry nails against steel will often ricochet and could break your front teeth.

Nothing else will give you that audible grit sound like a pick.
Yes we should be all as good as Steve, but you don't need to be good at welding to do an absolutely great job and what you'd build would pretty much always be stronger than something you could buy for the same application.
If in doubt then layer another bead or two on, as long as you follow that no.1 rule.

There must be no slag whatsoever, if you make a balls of it, then you take the grinder to it and go over everywhere with the nail.
Be ruthless, electrodes are cheap, so grind away until you have no sign of porosity.
A molten bead won't sit onto a surface if you have any.
If you have a hole in the weld, then you must grind into/around it to make an area that the bead will sit on, and not just sit on the walls of the hole

At worst case scenario, think of the weld as a 1/4" stick of warm blue tack , 
Attempt one single jab with moderate pressure into a crevice.
It likely won't penetrate into the hole and get caught up on the walls instead.
Then you have a pocket which is not acceptable.

Grind away until you have a nice wide gully with a clean bottom to lay a new bead ON, and not IN.

P.s Sorry about the terrible blue tack analogy


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## hawkeyefxr (14 Sep 2020)

TheTiddles said:


> Good advice, I burned the logo on my t-shirt onto my chest once
> 
> Aidan


Nothing like learning the hard way.


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## Lazurus (14 Sep 2020)

MIG Welding Forum



Full of advice and tips on all things welding for beginner. My vote would be a 180 amp R-Tech tig running Argosheld or Hobbyweld gas.


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## heimlaga (14 Sep 2020)

Cheap migs tend to be good at making people believe that they lack talent for welding.
Good migs aren't cheap. 

I have tested mig weding a few times and found it a lot more difficult tan it looks. I stick weld a lot and it took a bit of effort to learn but once learned it is a very versatile technique. 
Secondhand DC stick welders of good quality can be had for very little money. For the last 10 years I have used a 200 ampere Unitor rectifyer. Probably made in the 60-ies but as it was an absolute top of the line professional welder in it's days is is still very good by today's standards. Secondhand AC stick welders are even cheaper but that is because they are useless.
The greatest advantage of stick weldng is that it can be done outdoors even in windy weather.


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## bourbon (14 Sep 2020)

If it's thin I use my mig. If it's Thick I'll use either my Aldi arc cheapy buzz box or the Guardsman inverter arc. My welding isn't pretty by a long way, But it does stick two bits of metal together! Remember to budget for an Auto darkening mask, Made my life a lot easier when I got one. Leather gauntlets, and long sleeved non flammable jacket, chipping hammer (life is too short to water about grinding nails! they are only about a fiver) and a fire extinguisher is a good idea as well. Then Practice, Practice Practice


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## Ttrees (14 Sep 2020)

TheTiddles said:


> Good advice, I burned the logo on my t-shirt onto my chest once
> 
> Aidan



I hope that wasn't your favourite Steely Dan tee shirt!


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## NickWelford (14 Sep 2020)

What category do the SIP type wire fed welders come under? There’s no gas bottle involved


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## Jake (14 Sep 2020)

Kind of in between, flux cored wire. Generally regarded as the worst of both worlds.


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## Jackbequick (15 Sep 2020)

Lazurus said:


> MIG Welding Forum
> 
> 
> 
> Full of advice and tips on all things welding for beginner. My vote would be a 180 amp R-Tech tig running Argosheld or Hobbyweld gas.


To give an idea, a boilermaker who recently did some work for me used and an ancient 180A gas-less MIG. You may be aware that boilermakers especially having been approved with X-Ray are the cream of welders.Getting the current spot-on is a great part of good welding however penetration and width of weld are what gives the strength.

MIG users more so than stick welders use one (gloved) hand to support the other. Looking at how the molten metal is running and not rushing ahead is crucial. 

A well fitting helmet (maybe electronic) can cut out one of the nuisance aspects of welding. 

Try not to inhale the fumes.

Stick welding definitely has its place and it is not a poor welding method whether in ac or dc. That same (tradesman) welder of whom I spoke , has had a lifetime of expertise on pipelines etc. 

For stick welding he uses a unit about the size of two fists. That took me aback..._really?_...what cycling?...'continuous' he said......wow!! 

My portable stick welder is driven (ac/dc ) by a Fordson tractor engine!

Lumpy welds are likely to be weak. My suggestion is as one comment said...practice, practice,practice (each day) on the channel in a piece of angle iron....to relax, steady hand, control breathing to 'normal'. Look for examples of excellent welding and listen to 'how'...and by the way the welding 'sound' tells how well you are going....or perhaps do a welding course at Tech...there may be a short term course...or pay a welder to teach you.


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## Stu_2 (16 Sep 2020)

Did a limited amount of stick years ago. I was welding a boat trailer one day when a big lump of spatter landed on the tongue of my trainer (I know! I was young and foolish), leading to my first and only breakdancing performance… 

+1 for the MIG welding Forum. Great resource. I see they're still partnered with/sponsored by Weldequip, who gave a good service when I bought stuff from them.

A recurring theme when I was searching for advice on buying a MIG was to make sure it had a decent wire feed, otherwise I might struggle as a novice, and to make sure it had a standard Euro torch, as spares and consumables are cheap and readily available. The thing I’d add is if possible try and get something that doesn’t have a fixed earth lead. It’s a pain in the a***, and you might find you’re moving the welder around with annoying frequency on bigger jobs, and a real problem if you need to weld anything such as brackets at or above head height!

I’m no expert, but did do a fair amount of welding after buying the MIG, and found the following useful:

Auto-darkening helmet. You can also get magnifying lenses, which is great if your eyes no longer work like they used to.
MIG gauntlet for non-torch hand, and a thinner TIG glove for your torch hand will give a better feel for controlling the torch.
Using Tip Dip, and keeping the shroud nice and clean.
Flap discs (essential).
If fabricating from scratch, a second grinder is useful. Continuously switching between cutting discs and flap discs gets annoying, quite quickly.
If you’re in a small workshop, you might want to consider a couple of welding blankets. My workshop is tight on space, with stuff stored under the benches and in racking, and generally cluttered. If a bit a of spatter finds its way into a place you can’t see, you don’t want your workshop catching fire half an hour after you’ve finished and gone indoors for a brew!
Have fun.


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## Jackbequick (16 Sep 2020)

Stu_2 said:


> Did a limited amount of stick years ago. I was welding a boat trailer one day when a big lump of spatter landed on the tongue of my trainer (I know! I was young and foolish), leading to my first and only breakdancing performance…
> 
> +1 for the MIG welding Forum. Great resource. I see they're still partnered with/sponsored by Weldequip, who gave a good service when I bought stuff from them.
> 
> ...


HI...some very good advice there...

Circumspect of Chinese gear I nevertheless grabbed an 'electronic' helmet recently at Bunnings ...$49.00...interestingly the boiler maker who recently did some work for me had the same type of helmet...look a bit like a speedster helmet.

One thing...may sound pretentious I suppose...good welding shouldn't need grinding. When it is done you no longer really know the penetration which has been achieved and thus the strength. Having said that (you'd know it) , using the grinding tools _before_ welding is a key to success in what one produces....not just 'preparation' but_ 'correct'_ preparation for the weld. 

I noted with the boilermaker aforementioned, that occasionally he made almost imperceptible adjustments to his MIG (current not speed) during his various welds on same situation ..."just a tad, so fine'...that so-expert feeling he had developed over decades for having the flow "just so" with same sound of the arc all along. None of the welds needed prettying-up. "Funny" how fascinating it is to listen to that consistent sound and see the results of expert welding...admire the skill. 

On the other hand I watched with some 'dismay' a 'past- retirement' professional aluminium welder, who makes boat and jet-ski trailers, grind-away copious welding material. Maybe the trailers hold together, maybe not. I wouldn't buy one having watched the operation. I always look for a very neat and consistent weld with correct penetration...nothing needing to be hidden. 

I think I'd need a metre of practice to achieve it these days!


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## Redkite (17 Sep 2020)

Lazurus said:


> MIG Welding Forum
> 
> 
> 
> Full of advice and tips on all things welding for beginner. My vote would be a 180 amp R-Tech tig running Argosheld or Hobbyweld gas.


Another +1 for the welding forum, also covers arc welding, lots of good advice for beginners on techniques, equipment etc, definitely well worth looking at.


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## Spectric (17 Sep 2020)

As a total beginer and I assume no experience then the good old stick welder is a good starting point. Simple setup, only current to set and you want to weld what I would class as agricultural. Then if you want to progress I would suggest an evening class as you really need some theory as well as practical. MIG welding is ok if you get a decent welder that has the power, but it is easy to get a nice looking weld with little penetration. Modern invertor MIG welders are also a lot easier to setup than the older transformer types. Then you have TIG, my personel favourite and this is easier to learn if you have gas welding experience as you already have rod feed experience and using this process you can weld anything that can be welded.


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## Ttrees (17 Sep 2020)

That's not to say you can't make an invisible joint with the arc though.
Just not anything that's sub 2mm.


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## Jelly (24 Sep 2020)

heimlaga said:


> Secondhand AC stick welders are even cheaper but that is because they are useless.



Whilst I have access to big, 3-phase EASB MIG and DC Arc welders if I need them, the 140A buzz box I bought for £30 (for the £150 worth of high nickel content rods which came free with it) is generally sufficient for my needs to occasionally fabricate brackets, stands and the like.

So I would very much challenge that they're useless!

The old AC only units have their place but if the user doesn't understand the limitations, they will be endlessly frustrating to operate.


The biggest limitation is that AC Arc welding requires more control and finesse from the operator to _actually start and maintain the arc_, which *is* broadly incompatible with their position in the market as bargain basement entry level machines.

The reduced penetration compared to DC has to be considered too, but can be mitigated by appropriate joint design and prep, it's also occasionally a benefit (say when welding dissimilar thickness materials).


Overall the Oil filled AC units are pretty good for someone who welds infrequently and can't justify a lot of expense on a welder, but needs a machine to weld thick plates or do anything else which requires sustained periods of welding to deposit a lot of material.


The "Buzz-Box" air cooled types have pathetic duty cycles, but if you need to make short welds, and use it once in a blue moon they're fine for the price, I wouldn't want to spend much over £50 for one in good nick though.


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## highwood122 (24 Sep 2020)

heimlaga is not quite correct to say second hand ac stick welders are useless, if you can find one with open circuit voltage of 80v or 100v they are ok


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## hawkeyefxr (25 Sep 2020)

Jackbequick said:


> To give an idea, a boilermaker who recently did some work for me used and an ancient 180A gas-less MIG. You may be aware that boilermakers especially having been approved with X-Ray are the cream of welders.Getting the current spot-on is a great part of good welding however penetration and width of weld are what gives the strength.
> 
> MIG users more so than stick welders use one (gloved) hand to support the other. Looking at how the molten metal is running and not rushing ahead is crucial.
> 
> ...


Also try vertical and overhead for a challenge, remember not all jobs can be turned over easily.


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## Spectric (27 Sep 2020)

I cut my teeth on a big old oil filled Oxford stick welder and once mastered it could lay some very decent welds, providing the joint was preped and the rods dry, Stubbs rods were one of my favourites as the slag came away nicely to reveal a sound weld and it was always fun doing vertical up welds, as you said not everything can be positioned to suit the welder.


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