Thread: TIG question

Tig is better suited to thin stuff. I used mig on my bull/winch bar and had no problems. Mig is really easy to use where tig can be a lot harder to master, it's slower as well.
All the rust repair work I do I use mig with 0.6mm wire and it works fine. For any replacement patches I use 1.2mm thick sheet so it has a bit of body to weld to.

Dave

G'day Peter,

TIG (or look up GTAW as well) is very flexible and would do all the jobs you could use the stick function for + all the thinner metal work. BUT
- as DaveJ said - is harder to get the hang of
- you need a gas (argon) supply - starts getting expensive pretty quick
- you need a torch hangle, tungsten, and some other minor fittings
- some filler wire
- a very clean weld area (no rust, paint, oil etc - just bright metal.)
- a DC only machine can't weld aluminium (you need AC for that - more expensive)

I'm guessing your side steps are going to be made out of steel tube? If so, I would practice with your MMA mode and some light guage (1.6 or 2.4mm) 6012 or 6013 arc welding rods on some scrap tube. You should be able to weld tube down to around 2mm thickness without too much trouble.

Cheers

- Mick

Hi Peter

Something I have found (as a novice TIG user) is that when welding thinner materials (in my case <1mm) it is very easy to "eat away" the metal as such because there is no filler being added until you add it yourself and it melts into the pool. Getting the knack of being able to strike an arc and form a weld pool with some body behind it using the filler wire has been my biggest hurdle.

The quality of welder makes an enormous difference too. Our welder at work is a scratch start garden variety with no external control like a foot peddle or button start etc. I learned to weld with this and can weld (gorilla welds - ugly, but strong enough) most things between 0.032" and 3/16" with it but after using a whiz bang model with all the features last night it is easy to see the difference in welds just by swapping the welder itself. The extra features would definitely make the plunge into TIG a lot easier.

TIG is great, and a quite enjoyable form of welding, but it is hard to get that first bite at it. Good luck nonetheless!

Tom.

I have a 200A AC/DC TIG welder plus another 160A DC only TIG and taught myself to TIG weld to a reasonable standard (in steel, aluminium is a bit more tricky ). I'd suggest it's not that difficult if you have any experience with gas brazing, indeed you can TIG braze as well, something I'm about to try on some cast iron gears. Contrary to common belief, a filler rod is not required any more than it is in gas, the heat of the puddle can be used to fuse the two metals. Having said that, a filler is normally used. The dipping of the filler rod into the puddle is what gives the characteristic "stacked dimes" (as the Americans lik to call it) look of a nice TIG weld. Here's a picture of a bead I ran on 2 mm aluminium plate a while back to contrast the two. Sorry it's a bit crooked but I wasn't following any lines on the plate. You can clearly see the start of the bead at the top is without filler, the rest is with filler as one would normally do it. In fact the eagle-eyed will notice the bead actually runs bottom to top, so I actually ran a bead over the top of the previous.



If you're thinking of getting in to TIG welding I can thoroughly recommend it, it's one of my favourite shop activities to be honest. DC welding is very quiet and peaceful so I just listen to the radio as I'm welding. In addition to the welder itself you'll need to organise rental of the argon bottle. It's an area to shop around a little as the terms of rental can be somewhat difficult with big companies. An alternative are the disposable bottles, it's how I got started but can't recommend them. They're a VERY expensive way to get gas, and don't last very long at all. I think some of the small welding supply retailers can arrange short-term rental however and that may be more to your needs.

Hope that helps.

Pete

Thanks Pete. I am looking around for a cheapie tig torch. The BOC one was a shocker, no doubt very good but a shocker just the same. Yes I too am attracted to the concept of TIG I always felt much better when brazing and welding with gas. So are there any traps for young players with TIG torches? The guy at BOC said as long as they have 25mm DINSE plugs they should be OK but I asked a question on flea bay and the reseller said he wasn't sure about his ones as they weren't BOC torches???.

I think there's heaven and hell in welding! Heaven is when you don't know that you don't know and hell is when you do know that you don't know. Still I suppose I should just get some metal and blaze away.

FWOAH! Cast iron gears???? Man that sure sounds impressive.

Originally Posted by Pete F

An alternative are the disposable bottles, it's how I got started but can't recommend them. They're a VERY expensive way to get gas
Pete

You're not wrong! When I was first setting up my TIG, the disposable bottles were "recommended" to me. the best thing I ever did was not listen to this advice. If you're starting out - you need to practice. I get about 7-8 hours of welding out of a E2 sized bottle (from memory 4,100 litres) and I reckon I went though 2/3 of a cylinder just mucking about practicing. I forget what a refill costs but it's less than $200, and the cylinder rental is something like $45/quarter. Compare that to a disposable bottle with only 60 litres at a price of $30-$40 a bottle (this works out to be close to $2,500 for equivalent amount of gas)

I reckon if you're serious about setting up for TIG, set up a rental agreement, hire a reasonable size (say E2) cylinder or argon for a quarter, do all your practice and project welding in 3 months then return the bottle.

Cheers

- Mick

Yes you're right Mick. If I had bought the BOC 130 with TIG attachment, filler rods and gas it would have been over $600 all up! You're also right about needing to practice - obviously that's when you'd need it most. Hopefully I'll look at it again if I get a refund from the Taxman.

Originally Posted by pajeronj

Thanks Pete. I am looking around for a cheapie tig torch. The BOC one was a shocker, no doubt very good but a shocker just the same. Yes I too am attracted to the concept of TIG I always felt much better when brazing and welding with gas. So are there any traps for young players with TIG torches? The guy at BOC said as long as they have 25mm DINSE plugs they should be OK but I asked a question on flea bay and the reseller said he wasn't sure about his ones as they weren't BOC torches???.

I think there's heaven and hell in welding! Heaven is when you don't know that you don't know and hell is when you do know that you don't know. Still I suppose I should just get some metal and blaze away.

FWOAH! Cast iron gears???? Man that sure sounds impressive.

I can't say I'm surprised to find the BOC ones expensive, and possibly unnecessarily so from what you've said of your situation. Both my welders use the same DINSE plugs, however I believe there are different sizes. I think these are however the most common. However on a TIG torch you need to also consider there are 2 other leads, the gas supply and sometimes a switch unless you use exclusively a foot control. The gas and electrical fittings may vary between machines ... in fact probably will.

You'll also need an argon regulator for the gas, a gas bottle, and a way to thoroughly CLEAN the parts. That's the secret to TIG, the parts MUST be clean, you can't weld through crap as you may be able to get away with using other techniques. As they say, ya don't get nuthin for nuthin, and while TIG has the advantage of being able to beautifully weld pretty much anything, apart from the overheads of renting a gas bottle, it's very slow (compared to MIG) and requires the parts to be spotlessly clean. These is no flux used in TIG welding, the argon is merely a shield to prevent oxidisation when molten.

Mick, I also use an E size bottle, I used D size initially, but the rental is not much less, so while it was a convenient size, the D size is the way to go.

All in all, if somebody was looking for a general purpose welder TIG wouldn't be the one I'd suggest. Instead I think a gas/gasless MIG welder would be a better choice. The reason is it's much faster, you can get away with a lot more in the way of contamination, and if you have a big job you can rent a bottle for the job, then just keep some gasless wire for the times you just need it around for an odd job. Also any imbecile can use a MIG and lay a bead, it may not be pretty, but the chances are it will be structurally "ok" if not great. By the same token, a good welder can lay some awesome beads with a MIG and I've seen some MIG welds done by professional welders that absolutely blew me away with just how perfect they looked.

As much as I say TIG is quite easy, you do still need to learn and practice, indeed I was reminded last week that I probably need to sit down for an hour or so and simply run beads on aluminium plate to keep my hand in. I find if the aluminium welds are "ok", welding in steel is a piece of cake.

Pete

Well if it's going to cost me a further $400 to get my little BOC 130 to weld TIG, I might as well buy a MIG welder (... just waiting for a clip over the ears from dearly beloved)
Maybe get competent at stick welding first then shoot for higher targets?

Originally Posted by pajeronj

Maybe get competent at stick welding first then shoot for higher targets?

Oh gawd, to me stick is the hardest of the lot! Invariably my sticks are old, some cheap crap brand, full of moisture, and about -45 degrees. Needless to say I can barely even call the results of my efforts a "weld" ... more like 30 minutes of constant swearing before I give up, grind the lot off and TIG it

On the torch side of things you should be able to get a tig master valve torch setup for around the $180-200 mark I will price one up for you tomorrow and let you know.

Originally Posted by Pete F

Mick, I also use an E size bottle, I used D size initially, but the rental is not much less, so while it was a convenient size, the D size is the way to go.

Did you mean E size is the way to go? I've been meaning to work out if a G size would be better for me. I'm onto my 4th cylinder in a bit over a year and it's starting to hurt. I was thinking though, the little disposable bottles do have one advantage - portability to a remote site, so if someone does a lot of odd jobs I guess they have a purpose.

Originally Posted by Pete F

Also any imbecile can use a MIG and lay a bead, it may not be pretty, but the chances are it will be structurally "ok" if not great. By the same token, a good welder can lay some awesome beads with a MIG and I've seen some MIG welds done by professional welders that absolutely blew me away with just how perfect they looked..

I have to admit I've never used MIG but I get the impression that it would be possible to lay down a nice looking weld but with poor structural/penetration characteristics. My view is that at least if a TIG weld looks good, it probably is.

Originally Posted by pajeronj

Well if it's going to cost me a further $400 to get my little BOC 130 to weld TIG, I might as well buy a MIG welder (... just waiting for a clip over the ears from dearly beloved)
Maybe get competent at stick welding first then shoot for higher targets?

I was going to suggest that, but then again, unless you go gasless (which I gather has it's own peculiarities), then you're still need the gas (although maybe a cheaper mix). Before anything else I would practice a bit with the stick welder. You'll never regret the skills you learn and it'll make you a better welder regardless of which process you end up favouring. Get some good rods (search the welding forum).

Originally Posted by Pete F

Oh gawd, to me stick is the hardest of the lot! Invariably my sticks are old, some cheap crap brand, full of moisture, and about -45 degrees. Needless to say I can barely even call the results of my efforts a "weld" ... more like 30 minutes of constant swearing before I give up, grind the lot off and TIG it

I have to agree - you can get a somewhat acceptable TIG weld pretty easily. To lay down a perfect one is a completely different matter. The nice thing about TIG is that you can go at your own speed and see your mistakes evolving in front at a pace you can react to.

Cheers

- Mick

Mick I'm pretty sure it's an E size bottle I have now. I believe it's the most common type used anyway, and sits just over waist height I'd guess. When I changed it the guy in the welding store said the D size were pretty much only used by guys who needed portability. The only reason I'd have a disposable would be as an emergency supply in case I ran out of gas, but then again you can pretty much see the gas pressure and get an idea fron that how much is left.

The nice thing about TIG is that you can go at your own speed and see your mistakes evolving in front at a pace you can react to.

The other nice thing is if you don't like the weld, just go back over it and do it again!

I have to agree - you can get a somewhat acceptable TIG weld pretty easily. To lay down a perfect one is a completely different matter.

Do you do much welding in aluminium Mick? As I mentioned above, if I've been welding a lot in Al, switching to steel makes is so much easier. No more aluminium "no heat ... no heat ... no heat ... whoa!!! ... too much heat ... too much heat ..." For those who haven't TIG welded aluminium, it's a very efficient conductor of heat, so you start by desperately trying to get heat in to get a decent puddle, but once the material heats up it takes off like a thermo-nuclear reaction and the puddle can get away from you! Back off ... Back off!

Pete

Originally Posted by Pete F

Do you do much welding in aluminium Mick? As I mentioned above, if I've been welding a lot in Al, switching to steel makes is so much easier.

Yeah Hi Pete, I reckon half my TIG welding is aluminium - I think it is such a great material. There's a guy locally that sells every aluminium section you can imagine as well as sheet and plate - it's my favourite place in the world Probably the biggest drawback is the loss of strength/temper on thin sections after a lot of welds. In terms of welds I find the biggest challenge is outside corners on thin ally

I agree about switching back to steel - nice and theraputic ! Cheers - Mick