MIG or TIG advice needed

[Ciaranfox10]

Hey guys,

Looking for some advice on buying a new welder i cant decide between going for a MIG or TIG welder ive been looking in my local welding shop which are selling 160amp DC R-tech tig machine and 180amp SWP redline mig for close enough the same money.

Im into off road challenge comps and will be doing fabrication of roll cages winch mounts and chassis and suspension mounts etc. but i also need capability to weld light body work.

I fear the 180amp mig would be a bit over stretched on heavier stuff and more powerful versions seem to get very expensive

I like the idea of the R tech ive used TIG machines in college and i would love to get better at it plus it can be used as a stick welder which is a plus. But would it be as suitable for body work ?

Any advice much appreciated

Thanks Ciaran

 

[hotrodder]

TIG can certainly be used for bodywork but it's a very different approach to MIG... the typical technique is more akin to traditional coachwork with oxyfuel where distortion is accepted rather than feared and welds are planished out correcting distortion at the same time. Unless you're a dab hand with hammers and dollies (or want to learn rather than just fix/modify bodywork quickly/efficiently) then TIG will be a slow PITA. Without wishing to sound rude TIG welding overhead while lying on your back/doing an impression of a contortionist to reach bits of rollcage is VERY different to standing/sitting at a bench...

What's the thickest section you're likely to need to weld with regards to 'heavier stuff'? No idea about the SWP but if bodywork is on the list of jobs then one to watch with MIGs is their min output as some don't really go low enough

 

[Shox Dr]

TIG welding overhead while lying on your back/doing an impression of a contortionist to reach bits of rollcage is VERY different to standing/sitting at a bench...

Really I wondered why my back's in bits tonight

 

[Ciaranfox10]

Heavist stuff i would be welding would be about 6mm. I wont be doing alot of body work just the odd repair.

In an ideal world i would buy both but im a student at the moment and its alot of money so im just trying to figure out the best all rounder really.

When we done tig in college i liked it alot but as u said that was on a bench.

 

[hotrodder]

A MIG probably ticks more boxes imo. If it's a steady diet of 6mm could probably do with the next size up so you're not running the thing flat out all the time, in either case will really need more than a 13A plug

Really I wondered why my back's in bits tonight

That's called getting old The one that pees me off is your body just getting used to it as the job ends and having to go through it all again next time

 

[Ciaranfox10]

Will 40amp min on the mig be too high for 1mm thick sheet ? and will the 180 amp mig be up to welding 3/4mm roll cage tubing ?

Kinda leaning more towards getting the mig now

 

[hotrodder]

40A is a bit high (something with a 30A min would be better), at the top end a 180A mig should just cope with 6mm. If you haven't already found these then have a read here... http://www.mig-welding.co.uk/tutorial.htm and also look in the Weldequip shop- dunno if buying from there would make sense living in Ireland but the kit is probably better described with regards to capabilites etc than from many other sources

 

[Ciaranfox10]

Thanks for ur help hopefully il manage to make my mind up this week

 

[ChrisJohnsSculpture]

I would say that for general automotive work MIG is probably the best bet. Having said that TIG would probably be the best option for fabricating roll cages, all else being equal.

Form your description is sounds like it's a fairly even split of what would be the best single welder.

In terms of performance the big advantage of MIG is that it's pretty much point and weld which is a big advantage for the limited access and awkward positional welds which tends to go along with working on vehicles. For bench fabrication TIG does have some significant advantages though, especially for stresses parts.

 

[Ciaranfox10]

Ended up buying the R-tech being playing around with it so far and started my first real project with it but ran out of gas today which it seems to use alot of.

Cant really comment on the machine as all i have to compare it to is the TIG welding plants in college which i was told are twice the price. But it looks to be good quality and the torch is nice as is the digital display.

 

[FranV8]

Get a flow meter quickly! Saved me a lot of gas use.

If I'd read this post earlier I wold have said the running costs of TIG are a lot more in my opinion, you do get through the gas.

Glad you like your machine. What torch came with it?

 

[Ciaranfox10]

To be honest i was thinking overall it would be cheaper because i could use it in MMA mode to save gas.

I have it set to 8 Lpm as it recommended in the manual. Im happy with the welder but at the same time i would of liked to get the MIG.

What filler rods are best for stainless steel want to practice making up some pipes but i have alot of practice to do yet

 

[FranV8]

I run the acdc equivalent of your machine - I normally run 4-5 lpm without issue

 

[hotrodder]

Dual gauge regs are never that accurate with regards to flow rates. The ones supplied by Rtech are infamous for overreading a LOT. Plenty of threads here on the topic, either add a 'proper' flowmeter or set the flow rate using one of these (available from all decent welding suppliers)... http://www.weldequip.com/gas-flow-tester.htm

The type of stainless filler depends on the flavour of stainless being welded. Two most common suspects are 304 and 316 welded with 308L and 316L respectively although mixing and matching isn't a big deal for some jobs. If you go to the http://www.mig-welding.co.uk/tig-tutorial.htm section there's a link to 'welding different steels' which covers stainless amongst others. Searching the TIG forum for 'purge' or 'purging' will also get you a bunch of threads

 

[FranV8]

Sorry - should have said. I run an inline flowmeter (rotameter type - it's got the bullet shaped "float" in the middle of it) - I've never paid attention to the 2nd gauge on the reg, it's useless.

 

[Ciaranfox10]

How long should i roughly get out of a 9 litre bottle ?

I bought a 9litre rent free bottle for 130euro and its going to cost me 60euro to fill it

 

[Ciaranfox10]

Fitted inline flow meter today reading about 15 lpm the way i had it set turned down to 5lpm now so hopefully that will bring down the gas usage somewhat.