we thought we'd do a video on tig versus mig why we would use different ones um and why they're
kind of that why they are the main two types of welding you'll see in exhaust components
so the first thing which is the most obvious thing to most people is how they look um now forgetting
the the two examples we've got here look different
because of the the surface finish of the the actual tube what we've got are
two very visually different styles of welding so if we take these uh these joints here for example
we've got really small really precise tig welds here and then the kind of mig welded joint
we've got here is obviously much wider there's obviously a lot more material been put in here
this is really where the primary visual difference comes in it's just in how much
bigger mig welding tends to be dig welding isn't always nice colours you know golden or
rainbow colours like that sometimes you'll see tig welding that's really gray and oxidized but
what you see here with these mig welds is that's kind of your standard
um off-the-shelf exhaust type work so we've got like really wide weld bead and it's kind of
it's a it's a it's a it's a process that requires a lot less accuracy and a lot less skill
to actually carry out tig welding is essentially a two-handed one-foot process you know you've got
one hand that holds the torch one hand that puts the filler material in and then you've
got your foot which is controlling the power so it takes a long time to learn how to tig well
to a high standard um and and not very long at all to learn how to mig well to a high standard
so that they're the two like biggest differences in terms of
the the kind of visual of things because mig welding is a much bigger type of weld
it's much wider usually there's a lot more material that gets put in it means that you
don't actually have to be anywhere near as accurate with the fit up of the parts
you could have a gap between the two pieces you were trying to weld together and you'd be
able to mig weld that up no problem with tig that's just not possible you know you really
need really tight gaps and that means that the whole process is a lot more time consuming to do
we've got to make sure that everything is kind of millimeter perfect before we can even begin
the welding process and you just don't have that disadvantage with mig welding you can just
chop your pipe it doesn't really matter if it's that accurate and you can just
you know pull that trigger and and load it up with material which will which will bridge that
gap so tig welding is a much more time consuming process in terms of starting with raw materials
and ending with something that you can use on the car because it's a much slower
process not just in terms of the fit up but actually in the welding it takes a long time
to kind of go around the pipe and complete a full weld joint and it's much more precise with mig
welding you just kind of pull the trigger the material comes out and you can fly around stuff
so that so that that's that's where the big visual differences come in
and then when it comes to stuff like um
why it's better in terms of reliability and it's because with the with tig welding because it is
a much more precise process you can really control the heat input because you're doing that with your
foot so you can control the heat input and the amount of filler material that gets added with
each dab to that joint with mig when you pull that trigger the wire will come out at a preset speed
the amperage is set to a preset you can't adjust those things in the middle of the weld
so tig is a far more precise far more controlled type of welding and that's why you see it in
motorsport applications where they're looking for the you know they want the
most reliable thing possible they want it to be so reliable and the cost that
doesn't come into it and obviously because tig welding takes so much longer to do
the welding process and all the fit up involved it means that it is inevitably more expensive
and and that reliability comes in especially on things like downpipes so downpipes are obviously
at the very front of the exhaust system and that's where we see the most amount of heat
so the most amount of heat is pushing that material the hardest in terms of heat cycles and
the very peak temperatures it sees and that's when you need the strongest most reliable welds because
you're going to get those if if something's going to break it's going to be that it's going to be
in those kinds of areas on downpipes and things like that so you really want to make sure that
in those areas you have got the most reliable type of welding you can provide and that's
always going to be tig and again that's it that's why you will see it in motorsport applications
you won't see any mig welded down pipes or exhaust systems on a you know on a professional
kind of outfitted race car um and obviously never in like formula one or wood endurance
car or anything like that it's always going to be tig welded one of the disadvantages with tig
which is potentially a disadvantage but is mostly actually an advantage is that you must back purge
with tig so just like i said that how some tig welding you see won't be colourful won't be gold
or you know kind of like rainbow colours um it will be gray um not all tig welding you see is
back purged but it is critical because we need to we need to make sure that on the back side of that
weld as it's as it as it is welded the we've got argon gas which keeps the weld pool from oxidizing
we need to make sure that we keep it as strong and as nice as possible on the inside
so that means that it is an extra process so we we've got to make sure that we do that or
we end up with something that could potentially be less reliable than something that's mig welded
because mig melding doesn't necessarily mean unreliability but it does mean that
poor tig welding with no backward purge is most likely to be less reliable than mig welding
this is why you really have to do your research because just because something looks good
and this is where a lot of the chinese down pipes come in a lot of the chinese exhaust systems
you're never going to find any of those have been back purged they actually tend to do you
know quite a bit of cheating in terms of making their worlds look pretty as well they'll tend to
do a weld which will be gray and all oxidized and horrible and then they'll grind it down and then
actually pulse with the tig welder over the top of it and that's how they make it kind of look
attractive they're they're kind of cheating and and that means that actually underneath
you have got a weld that's full of oxidization and porosity and is probably not going to be reliable
so i guess to summarize tig welding if done correctly should be far more reliable far better
looking and more attractive than a mig welded part there's more skill and time involved in it
and you know to somebody that spends the time it takes to do tig welded parts correctly it's like
an art form you know it is a you know it's a very highly skilled job and you can be really bad at it
mig welding once you know the process um and once you've gotten you know a machine set
up people can learn to mig weld very fast with tig welding it takes hours and hours
but you do end up with what is ultimately a better product that will inevitably be more reliable
and it's something that you can be really proud of