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IanS1
22-11-2013, 07:23 PM
Currently looking into buying a welder, TIG or MIG?


My current preference from watching Youtube videos is TIG, looks like it might be an easier technique to master for the novice.


Would like to hear some thoughts on your personal preferences and why you might prefer one over the other.

deisel
22-11-2013, 08:08 PM
depends what you want it for, tigs more specialized aluminium/stainless etc.tigs fine for welding mild steel just not as practical to use as a mig if you have loads of steel to go at ,migs much faster,i also found tig harder to learn than mig.

EddyCurrent
22-11-2013, 08:21 PM
I'm not a welder myself but I have done many searches with regard to welders for the types of material used in cnc builds such as steel box section, never envisaged welding aluminium, and the one most recommended was MIG with stick welding second. A 150 Amp model seemed to be the ideal size for all round work and my Brother in Law says he found the small gas bottles lasted no time so it was better to go for a full size bottle if using gas, though I have no idea what the price difference is or how easy they are to acquire.

mekanik
22-11-2013, 08:27 PM
Hi IanS1
I own both, cheap DIY MIG set and a combination of bit's that allows me to do TIG. I got my TIG gear about 30 years ago after watching a pipe welder repair a three branch manifold off my Mini Cooper(got to get me one of these i said)
The amount of times it has pulled me out of the *hit it was money well spent, it is so versatile, you can see exactly what your doing and you know you have got penetration, and with Argon you will be able to weld Stainless & possibly Ally if you flash a bit extra on a decent inverter set. don't get your gas from BOC as the yearly rental is extortionate. and i had mine in my shed for years just to have it on hand for when something hits the fan. I have used the MIG set and i think with practice i could become competent, but still prefer TIG.
Regards
Mike

m_c
22-11-2013, 08:42 PM
MIG is far easier to learn, especially for steel. It's also one of the quickest welding methods, and if you use gas, requires little post weld cleanup. It will also tolerate slight contamination (i.e. rust/scale), unlike TIG which will errupt at the slightest sign of contamination.

TIG is one of the harder welding methods to learn. Best way to think of it is essentialy gas welding, but with an arc, however due to the sheilding gas it allows a far wider range of materials to be welded. It is an inherently slow welding method, and is far more suited where MIG or Arc can't be used. It's also more expensive for the required gas. Last time I priced it, pure argon was nearly twice the price of argon/co2 mix used for MIG welding.

Alot of TIG boxes are also capable of Arc welding, and are far easier to use for Arc due to the well regulated DC source (the cheap buzz boxes can be a right PITA to get going). However Arc takes a bit more practise than MIG, as the flux hides what's actually happening at the weld point, so you have to rely more on knowing how fast you should be moving so you lay down enough metal, rather than eith a MIG where you can see how much metal you've put down.
The same comments also apply to gasless MIG, as it's essentially Arc welding but with a continuous feeding rod.

My first preference is always MIG.
Arc gets used where either I have to run of a 13A socket, I need to use Low Hydrogen rods (the saviour of repairing carbon steel!), or I'm welding something where more heat/penetration is needed.
TIG is usually used when I want to play, or on the occasion I need to deal with Stainless.

EddyCurrent
22-11-2013, 09:15 PM
I need to use Low Hydrogen rods (the saviour of repairing carbon steel!),

I used to work with a load of welders and this is true, they always went for low hydrogen rather than mild steel rods.

birchy
22-11-2013, 09:28 PM
I've been fabricating for 22 years, so can shed some light on this much asked question. MIG is by far the easiest to learn and cheapest to run. It's ideal for mild steel down to 2mm - 3mm thick. Anything less than 2mm thick will be best welded with TIG, although MIG can be used if you "spot" weld to avoid burning through. Basically, use MIG if you're going to be building steel frames and welding thick(ish) materials and use TIG for anything like sheet metals, etc. TIG is also preferred for Stainless Steel and Aluminium, although MIG can also be used with the correct equipment and set up. Note that for Aluminium, you will need a welding set with an AC setting. These don't come cheap and will generally double the price of a standard machine. Buy decent quality kit. The Chinese welders on ebay aren't up to much I'm afraid. SIP and R-Tech are 'OK' brands...made in China but are of a decent standard and (more importantly) have UK based customer support, servicing and spare parts. For good machines, I recommend Oxford which are UK built. I've had my Oxford 180A MIG set for 20 years and it's never let me down despite heavy use.

TIG uses a LOT more gas than MIG and requires pure Argon which ain't cheap, so running costs are much greater vs MIG. For MIG, I've used CO2 "pub gas" for many years without any issues. Technically we are MAG welding because CO2 is an active gas and gives better penetration than Argon mixes. The only thing to be aware of is that you must get the fizzy drinks CO2 as it is pure, whereas the beer gases will have nitrogen, etc in them. At 10 a bottle, no deposit and a lifespan of several years, it's a no brainer. There's a bit of an urban myth going around that CO2 is crap but very few (if any) of the "welders" saying it have actually used CO2.

deisel
22-11-2013, 10:09 PM
CO2 is an active gas and gives better penetration than Argon mixes. There's a bit of an urban myth going around that CO2 is crap but very few (if any) of the "welders" saying it have actually used CO2.
birchy ive used up 100,s of bottles of argon as a former welder fabricator with variuos fab shops much nicer welds with argon ,the co2 is crap and commonly used in the car trade and back street garages in my neck of the woods at least, i scored a fair bit of it from them for side work from home, both will do the same job but theres a noticable difference between the two when using it.

m_c
22-11-2013, 10:21 PM
I'll second Diesel's comment, although I wouldn't say CO2 is crap, it certainly is not as good as using an Argon mix, especially if you're working on thin metal.

deisel
22-11-2013, 10:35 PM
I'll second Diesel's comment, although I wouldn't say CO2 is crap, it certainly is not as good as using an Argon mix, especially if you're working on thin metal.
yeah craps a bit harsh ,perfectly usable and its got me out of many a hole .

Boyan Silyavski
22-11-2013, 10:56 PM
Hi there,

Actually i had the same dilemma before a couple of months. After spending a month reading forums and watching Youtube videos i decided on my choice.

For the price of a decent MIG and much under the price of a decent TIG or combine machine, I became an owner of 2 very good machines. Yes, Chinese, but not so crappy as many lead you to believe.

I feel that owning those 2 covers the basic needs of any hard DIYer, or even a small shop.

I acquired them in different order, but here is the order i recommend:

1. MIG+ ARC welder in one , 250A (http://www.ebay.es/itm/MIG-250AI-Schutzgas-Inverter-Schweisgerat-MIG-MAG-E-Hand-IGBT-250Amp-230V-/380517310579?pt=Schwei%C3%9F_L%C3%B6ttechnik&hash=item5898996073&_uhb=1)

This is unique as its 2 in one, 250A and at the time of my purchase there was no other similar machine, specially at that price. i bought it for 310eu, now is a bit more expensive i see. Works great and is my workhorse. the mig melts 10mm steel like a butter.

2. 200a Pulsed Tig+Arc+ 50a Plasma (http://www.stahlwerk-schweissgeraete.de/en/ct-520-puls.html)
This is the second toy. 5 year warranty should clear your doubts

Both work great in all modes, the Mig I still use with cheap C02 bottles.

And by the way you can weld aluminum with any of them. With the stick, the mig or even with the DC tig. Search you tube if you have any doubts.


I had many reasons why exactly these 2, but the main are-price,quality,versatility, run on 230v 16a household supply/yes even the 250A MIG/ ,. Even if a board is faulty, at aliexpress a board is 100eur.

PS. Every one of them payed itself by the first job i used them for


Hope that helps

birchy
23-11-2013, 02:30 AM
Granted, Argon mixes can give a better looking weld for inexperienced welders but once you learn how to set up correctly with CO2, it's more than adequate for home use, particularly at a fraction of the cost of Argon mixes. Personally, I'd rather buy a decent 2nd hand machine than a cheap Chinese one. Main reason is that I don't have much faith in Chinese electrical goods as they use low quality components to achieve the low prices. I very much doubt a Chinese welder would last 20+ years but I'm willing to be proven wrong...

IanS1
23-11-2013, 12:59 PM
Thanks for all the advice folks. So MIG it is then.

What about amps? I need the welder for my machine frame which is mostly 100 x 100 x 5mm, a little research suggests I need something up in the 250amp + range. This should cover 5mm and give me the option of welding thicker box section if needed in the future.

I'm not going to be production welding so how important is the duty cycle? If I aim for something around the -35% @ 250amps, would that be sufficient?

birchy
23-11-2013, 04:49 PM
180A with a decent duty cycle (60%+) should be sufficient up to around 8mm thick. A 200A - 250A machine will have plenty of head room as you'll only use 100A - 150A for most DIY jobs. The extra ooomph may come in handy when you have some thick plate 10mm+ or your local farmer drops his tractor bucket on your front lawn for you to repair. I see the Oxfords are now 600. I paid 400 for mine 20 years ago and it paid for itself the first week due to my first car being a Vauxhall Nova which seemed to need new sills and rear wheel arches twice a year.

What sort of budget are you working to?

IanS1
23-11-2013, 05:37 PM
Thanks birchy. No fixed budget as such, just want something reliable and to give me some headroom on plate thickness, 10mm + should be enough. The Oxfords look more than suitable and I've also looked at Portamig, any idea on reliability of these? I know you can get cheaper but I do like to support British manufacturing whenever possible.

birchy
23-11-2013, 05:53 PM
I've not used Portamig, so you'd have to do your own research on that. Obviously I rave about the Oxford welders because they're just good work horses. Just ask anyone who's owned one of their oil filled arc welders - most of them are about 40 or 50 years old and still going strong. Butters are decent quality, as are Esab, Miller, Lincoln, etc. Keep an eye on the power supply required. Many of the 200A+ machines will require a 16A supply. Even my 180A welder will take out a 13A fuse at the highest setting. I now have a dedicated 20A MCB for the welder socket.

I'd also make sure the welder can take a 15Kg spool of wire. It's much cheaper to buy the large spools as they're "industrial" size. Plus it indicates that the machine is capable of doing some man-work. If you're not sure what diameter to get, 0.8mm will be suitable for pretty much everything. If you'll only be welding 5mm+, then 1mm might be a better choice.

IanS1
23-11-2013, 06:15 PM
Thanks birchy, I'll look into those makes. No worries on the power supply, I've just moved into a workshop with 240 & 3 phase supply, I'll get the leccy to install whatever breaker/socket is needed.

birchy
23-11-2013, 06:56 PM
I've just moved into a workshop with 240 & 3 phase supply
In that case, it might be worth looking for a used industrial machine. They're usually fairly cheap because not many people will have 3 phase. Have you got a Saracen near you? They're a local company who supply workshop equipment and often have reconditioned/serviced machines they've taken as part-ex.

m_c
23-11-2013, 09:44 PM
If you have 3 phase, get a 3 phase welder!
The 3 phase means you get a far smoother DC supply, which translates to smoother welding, and as birchy says, because very few people have 3 phase, 3 phase welders go for peanuts secondhand.

corkcnc
24-11-2013, 12:39 AM
I think if it's a case of one or the other I'd go with the TIG. As been mentioned, TIG will get you out of a lot of tight spots in mild steel, ally and ss so it's pretty versatile. If you have a lot of mild steel welding though in terms of a large frame then MIG is twice as fast and simple once you get your set up and angles right.
However if it's an outside job on a windy day, welding gate posts etc.. my ancient Pickhill Bantam kicks ass everytime. (Once you have someone to reset the trip after the inrush into the coils knock the mcb).
Still for a lad with a workshop or garage I'd still go for TIG. The control you can achieve lends it to many applications. Even putting holes in work hardened stainless when someone calls over after trying to drill a hole in ss with high speed on their battery powered drill....(clamp a heavy washer around the hole first to limit the burn.)
Definitly agree about gas bottle rental. Don't dream of taking out a rental contract on your bottle, even the small ones. Pick on up second hand is your best bet.

magicniner
24-11-2013, 11:44 AM
with Argon you will be able to weld Stainless & possibly Ally

If buying a MIG pick a good one and it will be easier to learn and produce good work than one with less-good characteristics. I have an ESAB MIG that's great on light mild steel with CO2, for heavier sections a mixed gas like Argoshield is better and with pure Argon and the right wire it happily deals with Aluminium, Stainless Steel, Bronze, Copper, Brass and makes a lovely job on Cast Iron (with pre-heat and insulated slow cool), pick the right gas and wire and you can weld/braze most of the above (except Aluminium) to any other of the above.


Tig is easier to pick up if you've gas welded to a standard where your welds are a lovely neat series of half-moon shapes, you understand about maintaining a weld pool and where using filler keeping the rod tip at the right temp and dipping it to add filler. If you need to work with thin Stainless or Aluminium Tig and Gas are by far the best options.


MMA (Stick) is brilliant for heavier work in most materials, building up worn surfaces on machinery and hard facing, it's also excellent for outdoor work as not relying on gas for shielding it's tolerant of wind and even a bit of rain when you need to weld a hinge back into your neighbor's gate post on an inclement day.


I would have all three if possible, but if choosing one it depends on the intended use.
If you want pretty welds in light materials then your only option is TIG, also TIG if you're predominantly working in Aluminium and Stainless in a workshop.
Generally speaking if you're working with materials above 1mm and you're happy with some post-welding cleanup on finer work then a MIG will do the job nicely, I've built Mini-Skips outdoors on a calm day with a MIG ;-)
Never underestimate Stick, on fabrication work it will perform and produce a lovely job outdoors where MIG and TIG will struggle to function,
Regards,
Nick

birchy
24-11-2013, 05:03 PM
I'd have to agree that Mig will do most jobs but there are occasions when TIG and ARC are more suitable. If you have a workshop and 3-phase, then I'm assuming you're setting up something a bit more professional than a garden shed workshop? If so, get a 3-phase MIG welder and a small inverter TIG/ARC. The latter will often be combined into one set as they're almost identical electrically. Inverter driven arc welders are an absolute joy to use. I bought one of these last year for 300. It's been better than expected, however it drinks Argon faster than I can drink scrumpy!

SIP (S.I.P) 05266 Weldmate Welder P178 (160amp) HF Tig/MMA/Invert Welding | eBay (http://www.ebay.co.uk/itm/121084614061)

magicniner
24-11-2013, 05:57 PM
MIG ......... It's ideal for mild steel down to 2mm - 3mm thick. Anything less than 2mm thick will be best welded with TIG.

That's innacurate information and as a former Vauxhall Dealership Panel Beater and Jig Operator I can inform you that body steel down to 0.8mm is easily welded with MIG and CO2, ESAB set bodyshop proceedures for this using 0.8mm wire, thinner material than this is better welded with 0.6mm wire, some good MIG sets designed for lighter work will have an intermittent setting to help welders who are unable to deal manually with thin material,
Regards,
Nick

IanS1
24-11-2013, 11:48 PM
Thanks for all your advice folks. I'll have a good look into a 3 phase and good look into MIG in general.

birchy
25-11-2013, 02:18 AM
That's innacurate information and as a former Vauxhall Dealership Panel Beater and Jig Operator I can inform you that body steel down to 0.8mm is easily welded with MIG and CO2, ESAB set bodyshop proceedures for this using 0.8mm wire, thinner material than this is better welded with 0.6mm wire, some good MIG sets designed for lighter work will have an intermittent setting to help welders who are unable to deal manually with thin material,
Regards,
Nick
I didn't say it CAN'T be done. For "on the bench" type work, TIG does a nicer job of sheet metals and gives better pool control, particularly for none-expert welders. I also said that thinner materials could be welded but you generally have to "spot" weld to avoid burning through if you're not an expert. I've welded cars with an arc welder in the past but I wouldn't recommend it.