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View Full Version : Mig or ARC Welder... What should i go for?



AdCNC
14-04-2011, 12:56 AM
Hi Guys ive got alot of box and mild steel plates to weld ranging from 5mm up to 10-12mm at the moment ive only got a old sureweld 120 ARC, thats ok for 4mm stuff but even then it cuts out after 10 or 15mins of use (abuse).

Ive been looking at the Oxford welders on MigTigArc's websites, but these are MIGs
i also like the look of the kemppi welders but if im going to splash out on a good welder i want to make sure i get the right one for the job.

So what would be best a modern Arc/Inverter or a good MIG Something like the Oxford270

m_c
14-04-2011, 02:07 AM
ARC or MIG will do for what you're wanting to do.

Main points to consider are -
MIG will be quicker/cleaner but you have the additional cost of sheliding gas (and the associated rental).
A good inverter will be far more versatile, as it will give you TIG capabilities, which is very handy if you ever do thin metal work.

I've got a Clarke 255TE MIG, which does the majority of welding, including anything from 0.8mm sheet upto 1/2" plate.
I've also got a Cebora inverter (ebay bargain!), which is ideal for heavy jobs where it's just not practical to haul the big welder to (plus there is the issue the MIG needs a 32A power supply), but also gives TIG capability for anything involving thin metal.

wiatroda
14-04-2011, 09:05 AM
Why not TIG ??? Still need to use argon, but it gives you extreme weld quality. You can weld from very thin to thick steel. Since I bought a TIG welder I dumped my MIG, it just outperforming all other welding techniques. It have stick welding option, so I can weld with sticks as well.
Gas: I rent of argon cylinder - 6 per month, to fill it up something about 50 and it last sometimes for months( I don't weld a lot )

m_c
14-04-2011, 12:21 PM
TIG would never be my first choice for anything over a couple mm thickness, because it takes too long, and at the thicknesses stated, you'd be needing a water cooled torch so you could still hold the torch after a couple minutes use. Plus on thick metal, the heat put into the parts you're welding is far higher than MIG or ARC.

Also pure Argon is a good bit more expensive than MIG gas, as it costs more to produce pure argon.

wiatroda
14-04-2011, 12:53 PM
Yes, I agree, it is slower and you need pure argon ( for MIG you can use cheaper CO2). Some sources claim a thermal distortion is lower in case of TIG welding so I assume the heat you put into material is lower as well. The thickest part I TIG welded was 8mm steel plate with 16 mm bar, but it was at the very beginning of my TIG welding adventure with little experience in welding (see pic below) and I'm by no mean I was professional welder.

3948

Of course it is possible to weld with sticks If there is an option in TIG inverter. In summary TIG initial an running cost is higher, but there is no spatters, post weld clean-up and is more precise. You just need to decide what needs do you have and choose suitable welding technique.

AdCNC
14-04-2011, 01:24 PM
Hmm Choices choices... im Tempted go with the Oxford 270 http://www.migtigarc.co.uk/MIG_Welder/mig_welder.html for the money and output it dont look a bad machine! What you guys think?

Web Goblin
14-04-2011, 01:46 PM
AdCNC
Pm sent.

Regards

Ian

m_c
14-04-2011, 02:14 PM
Yes, I agree, it is slower and you need pure argon ( for MIG you can use cheaper CO2).
Pure argon is expensive. I'm sure last time I checked, it was almost twice the price of Argoshield at BOC.
Although you can use CO2, it's far better to use the proper mix, as it does lead to better welds. The proper mix is Argon with a percentage of CO2 (the higher the percentage, the hotter/deeper the weld will be) and a trace of oxygen to help burn of any impurities.

Also, some CO2 isn't pure CO2. Some suppliers add nitrogen to make it useless for welding.


Some sources claim a thermal distortion is lower in case of TIG welding so I assume the heat you put into material is lower as well. The thickest part I TIG welded was 8mm steel plate with 16 mm bar, but it was at the very beginning of my TIG welding adventure with little experience in welding (see pic below) and I'm by no mean I was professional welder.

It all depends where you're measuring the distortion. As you can see in that photo by the blueing, the amount of heat has been high and has travelled pretty far. The plus side is the weld will be relatively free from thermal stresses, but you end up with a far bigger heat affected zone. With MIG (set so it's short circuit transfer) or ARC, the HAZ wouldn't be anywhere near as big, but the thermal stresses within the weld will be higher. It all depends on what you need from the weld.

I'm not a professional welder either, but I do have my MIG/MAG certificate (mainly so the employer can cover their ass should I put anything up flames!), and have had plenty experience bodging bits together using various combinations of welders to of learnt some of the things that are possible.




You just need to decide what needs do you have and choose suitable welding technique.

birchy
14-04-2011, 05:04 PM
I'm a City & Guilds 229 I, II & III qualified welder and fabricator and used to work for a company who build steel bridges, electric pylons, sub stations, etc. I've owned an Oxford 180A mig for at least 15 years, am a ham-fisted bugger and have made more gates and wrought iron work than I care to remember. It takes 15Kg spools of wire and I'm currently on spool number 5 or 6. Other than replacing a couple of tips, the trusty old Oxford hasn't had any new parts and just plods on forever and ever. I very rarely need the full 180A but even when I do, it can still lay about a metre of continuous 6mm fillet before it cuts out on overheat. I can only remember a few occasions where I actually worked it so hard it needed a 10 minute cool down.

Stick a reel of 0.8mm wire on it and get a bottle of CO2 from a pub or pub gas supplier. It'll be "food grade" CO2 if you get pub/fizzy drinks gas so it will be guaranteed pure. Argoshield does give a slightly better weld finish but CO2 costs 10 a bottle and no rental...

AdCNC
14-04-2011, 06:05 PM
Cheers Birchy :beer: ill have to look into that then, the oxfords do look a good machine.

WSD
05-12-2011, 02:20 PM
I happen to think that Mig Welders (http://www.weldingsuppliesdirect.co.uk/welding/Mig_Welders.html) are the better of the two options. Very good machines.

WSD
08-12-2011, 02:01 PM
In my opinion Mig Welders (http://www.weldingsuppliesdirect.co.uk/welding/Mig_Welders.html) are about the best whichever one you go for but i do think that it is an individual choice and not everyone will agree. Do plenty of research into all three - i mean Tig Welders (http://www.weldingsuppliesdirect.co.uk/welding/Parweld_XTI_201_AC_DC_Tig_Welder.html) are good too. A lot really does depend on what you use them for. :confused: