|
|
|
|
|
|
|
|
|
Glen
Experienced Roboteer
Joined: 16 Jun 2004
Posts: 9481
Location: Where you least expect
|
Mig can be gasless, but its horrible. Avoid like the plague unless you have to weld outside in a hurricane or something.
Got some more time to type now so here's my assessment, take it with a grain of salt
Mig is good for heavy fab - making trailers, big framework, or when you need to make lots and lots of parts quick. Once you learn how to use the machine, setting the wirespeed and voltage is easy enough.
But you only get one go to make it look nice, not too hard when you get good at it but very few seem to be, Its as messy as a stick welder (spatter and smoke and sparks n shit go everywhere) plus tacking up delicate stuff is a pain in the ass cause unlike a tig, the wire has to touch the part to get started so that normally knocks the part away.
Very easy to get a cold weld on a mig too, were the weld sits on the joint without fusing into the metal.
Aluminium on the MIG is straight up horrible in my experience. Doing it via short arc (the normal way with steel) works and looks okay but its not strong at all. Spray arc is very strong and not that hard but can only do thicker metal and holy balls is it messy. I tried it a few times and smoked out the whole workshop
Also have to use a different gas (pure argon vs the argon mix for steel) for the aluminium too.
Swapping the torches and wire spools gets old fast, trust me you'll do it once then probably never again.
Now - TIG. Tig is like soldering on steroids. The torch has an electrode that doesn't get eaten away (in theory!) and you dip the filler rod in with your hand, like solder.
Biggest advantage for me is you can tack things up very delicately cause there's not much force on the part given nothing touches it, and can go back and reweld anything that came out bad as you don't have to use the filler.
Aluminium welding while tricky, is much nicer than with the mig and easier to set up for - don't need to change gas and wire spools etc. Just grab a different filler rod.
Personally the learning curve is less steep. People think mig is easier to learn but IMHO spraying bird shit weld at something and half sticking two parts together doesn't mean you know how to do it. Getting a strong TIG weld is easier once you got shown or told the raw basics.
Also much cleaner and just nicer to use - no spatter and silent (ac mode for ali gets pretty loud though). Don't have to armour up to weld anything, just throw a hoody on and weld away at 2am in your boxers lol, that's how half of decimator got done
Disadvantages are tungstens are expensive, however they last a LONG time, gas is expensive ($460 to buy the bottle and $160 for a refill which lasts me about a year and a half) plus a little bit slower. Unless you are making 200x of something that's moot.
Like Don says, they all have their uses. It all boils down to the sort of work you see yourself doing. _________________ www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz
Last edited by Glen on Thu Nov 19, 2015 9:53 am; edited 1 time in total
|
Wed Nov 18, 2015 10:30 pm |
|
|
Spockie-Tech
Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
|
+1 for Glen comments.
I used a friends MIG a lot, then bought myself a DC HF Start TIG welder + Plasma Cutter) (now looking to upgrade to AC for Ally when the budget allows).
The TIG is much *slower to weld lots of stuff together, you wouldnt try to build a trailer or a heap of angle-iron shelves or anything with TIG, but since nearly all TIGS also do Arc/Stick welding mode, I just switch to stick mode if I have to glue any large amount of big steel chunks together quickly.
And Stick welding is great for burning through nearly *any crap on the steel construction without giving a damn. The stick rod coating is a flux as well as a shield and floats any crud in the weld pool to the top to be chipped off when it solidifies. So paint, mill scale, small amounts of oil/grease, you just burn on through it. The gas shielding in Mig and Tig *doesnt act like a flux, so you have to get all the crud out of the way first.
Migs arent *quite as fussy as Tig cleanliness wise, but if you want *quality welds, they require nearly as much pre-weld cleaning of your parts for good adhesion.
So while its a bit smokier and messier than Mig, I think Arc is better (in some ways) than Mig for fast, low precision building of big heavy stuff. You dont have to constantly stop and clean the gun either, which often clags up and jams with Migs. You do have to keep stopping and changing the Rod of course though, so its probably much the same overall speed wise.
Also as Glen once said, while Migs dont make quite as much smoke as sticks do, they still throw out an incredible amount of sparks, which will set anything within a meter or so of you on fire, including you. You get almost as much spatter/BB's as a stick weld all around your Mig welds too.
Tig is slow and fussy (joint prep), but neat, clean, quiet and precise. But the ability to easily switch to stick for quick, messy, smokey/sparky, bulk welding means a Tig is really a 2-process machine. (If not a 3 process if its a Plasma cutter as well, which many are).
Migs are sort of in the middle.. The fast one handed "Hot Glue Gun" aspect of them is nice, but the sparks, jam ups, joint cleaning, spatter, etc are annoying, they dont offer the same precision clean/quiet work as a Tig and a Mig is always only a Mig (unless you buy a $5k multiprocess machine) so you dont have the ability to switch to Arc mode (which is also useful when you dont want to burn gas, or have run out)
I think Gary uses a Mig for nearly everything, but hes been using them as a day job for years, so its probably 2nd nature to him
*edit, hah, Glen updated his post while I was typing this and already said pretty much everything I Did. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
|
Thu Nov 19, 2015 9:37 am |
|
|
|
|
|
|
|
|