TIG critiques?

[dstealth]

Well since I've now got my big bottle of argon from Energas, I've been practicing quite a lot with the TIG. My set-up includes a twin-gauge argon reg. complete with separate flowmeter for accurate gas flow. The photos are rubbish because I dont know how to take good quality photos, but I've tried my best. I was welding 0.7mm mild steel at 10l/min using 1.6mm filler and 1.6mm 2% Thor. Tungsten. For the elitists out there, what do you think?

 

[^neo^]

Try welding 2 bits of metal together

 

[dutchman]

Except for the burn through it doesn’t look too bad I think….
My results do not look much better
10 l/min argon sounds a bit high on the thin stuff though. I can get away with a lot less, approx 6 l/min.

 

[matt1978]

As Dutchman said, maybe could decrease the gas flow a little.

How considering its only 0.7mm thick steel, thats pretty good

You maybe be better with a smaller dia filler wire, because the amps needed to melt the filler are way higher than required for the 0.7mm parent material. You wouldn't get as much burn through then......try some small lengths of your mig wire.

 

[dstealth]

As Dutchman said, maybe could decrease the gas flow a little.

How considering its only 0.7mm thick steel, thats pretty good

You maybe be better with a smaller dia filler wire, because the amps needed to melt the filler are way higher than required for the 0.7mm parent material. You wouldn't get as much burn through then......try some small lengths of your mig wire.

Thanks Dutchman for the advice on the gas flow. I'll decrease it to six and see how it performs. Matt, I've only got 0.6mm MIG wire which is really too thin to be of practical use as a filler rod - 1mm would have been better. I've been told that you can get proper TIG filler rods less than 1.6mm, but they're not that common so 1.6mm is normally the smallest standard rod. It may be worth hunting some down though, because I'll only really be working with thin metal.

I'll try and do some butt joints and post them on here.

Chris

 

[matt1978]

You can get 1.0mm Tig rods, but I think they will be expensive. You could get some 1.0mm or 1.2mm Triple Dioxidised mig wire, it'll be cheaper but it depends if you can use the Mig wire as mig wire later........if not then you'd be best getting the 1.0mm tig wire especially if you have a lot to do!

 

[malcolm]

what do you think?

I think you are crazy practicing TIG on 0.7mm sheet. That's exactly what I did and it'd not too bad laying welds, but when you butt weld two sheets it's really tricky to get going without blowing a huge hole. I moved to 1.5mm and it was much easier to practice joints before going back to the thin stuff.

 

[TonyWilk]

I think you are crazy practicing TIG on 0.7mm sheet. That's exactly what I did and it'd not too bad laying welds, but when you butt weld two sheets it's really tricky to get going without blowing a huge hole. I moved to 1.5mm and it was much easier to practice joints before going back to the thin stuff.

I'd second that... not only is thin stuff really easy to blow holes in, but 1.6mm (or thinner) TIG wire is harder to use than, say, 2.4mm because it so easily melts into a blob-on-a-wire as you approach the arc if you're not quick enough.

Probably easier to polish up your technique on thicker stuff before getting frustrated with thin material.

Yours,
Tony Wilk

 

[mcfearn]

i used to practise on s/steel brick ties
about 4mm thick

 

[dstealth]

I think you are crazy practicing TIG on 0.7mm sheet. That's exactly what I did and it'd not too bad laying welds, but when you butt weld two sheets it's really tricky to get going without blowing a huge hole. I moved to 1.5mm and it was much easier to practice joints before going back to the thin stuff.

That's exactly the case Malcolm. I haven't actually yet managed to do a butt weld (or lap weld) with the setup I'm using! It just burns the edges of the sheet away or just blows holes straight through.

I didnt think it was necessary to practice on thicker sheet as that's not what I will be using eventually. Thanks for the info about the filler rods Tony - I was told I would be best off with 1.6mm rods, but I might try some of the 2.4's now that you've mentioned it. I think I'll be sticking with the 0.7mm steel for the moment though as I have a big sheet of it.

Chris.

 

[TonyWilk]

...Thanks for the info about the filler rods Tony - I was told I would be best off with 1.6mm rods, but I might try some of the 2.4's now that you've mentioned it. I think I'll be sticking with the 0.7mm steel for the moment though as I have a big sheet of it.

Chris.

Dunno if this is "acceptable practice", but I've found I can "cheat" a bit on thin material... lay the end of the filler on the join and start the arc up right next to it. Since you're immediately 'welding' and there's more metal there, it does help prevent that initial blow-thru.

You can even hold the filler low and steady and just move the torch like doing a fusion run (instead of dipping the filler in and out).

I'll leave it to the other more experienced welders to tell me if this is A REALLY BAD HABIT or not

Yours,
Tony Wilk

 

[matt1978]

It can be done like that Tony and it is a little easier, but you must be sure that you have good fusion to the 0.7mm........it can also lead to a very "proud" weld sticking up that is extra work to grind off if you need it flat after.

 

[dstealth]

Would it also be advisable to use a bigger sized tungsten? - I'm currently using 1.6mm.

Someone recommended using the Miller calculator for the consumables - think it was Shenion. So I went off what the calculator told me.

Chris

 

[shenion]

The miller calculator only goes down to 1/16". 0.7mm is less than half that. I would think a 1.0mm tungsten would be more appropriate.

 

[Drains]

I'm sure a 1.6 tungsten would be fine, but make sure it's ground to a long point to concentrate the arc.

 

[dstealth]

I'm sure a 1.6 tungsten would be fine, but make sure it's ground to a long point to concentrate the arc.

Cheers Simon. I do try and grind them to a longish point. 1mm tungstens seem to be hard to come by as well. 1.6mm seems to be the lowest 'common' tungsten.

Chris.

 

[GeorgeB]

That's exactly the case Malcolm. I haven't actually yet managed to do a butt weld (or lap weld) with the setup I'm using! It just burns the edges of the sheet away or just blows holes straight through.

I'm shocked to hear all the warnings about TIG blowing holes through sheet of around 0.7mm thickness. I thought thin sheet was what TIG was all about. Perhaps I'll drop ideas of getting set up with TIG gear.

 

[malcolm]

The advice was to avoid trouble in learning TIG. I'd advise anyone learning MIG not to start on 0.7mm sheet as well.

Get really good at TIG and with the right machine you can weld kitkat wrappers, but again not the best place to start off learning the process.

 

[Weldingartisan]

That made me smile Malcolm, thought I was getting on quite well with ally welding a while ago - found a roll of Baco foil lying around, click! flash! puff! where's that foil gone? Always worth finding one's limitations! W/A