Thread: TIG Welding Aluminium back for more Q's

new torch arrived its not much bigger it came with a few accessories but i think all the collets are the same 3.2mm size so i will need to buy some to suit the 1.6mm tungsten, i will test the torch tomorrow when i get a new cylinder of argon

If you're buying some collets, get some 2.4mm ones too - and matching tungsten. This size is a good all round size that I use for just about all my welding.
The tungsten I use is 1.5% (or some of them are 2%) lanthanated. The 1.5% have a gold band and I use them for stainless, ally, steel. I don't even have red or white tungsten's - no need.

Agree with Mick with using 2.4mm, much more universal. Ive tested all the tungsten types on ally and was using 2% lanthanated as my preferred type until I gave the BOC rare earth ones a go. They are a 3 mix type tungsten and I give them a big thumbs up

ive been playing around with the welder and new torch ive ran 2.2 meters of weld i think im going thru heaps of gas so far used 1/4th a D size tank using around 7L

the new torch became heavy after a while but it stayed cool enough to keep welding

Looking better gazza,

Circled red bits look best to me.
gazza.jpg
With your fit up... which version are you doing?

Good:
good.PNG


Not so good (minimal penetration):
Not Good.PNG

That weld is much better than you were getting before. Always a bugger to weld over ground areas, so I reckon you probably had a bit of trouble there.
Just need to work on fusing both sides of the joint and getting more consistent with your travel and addition of filler material.
A D size argon cylinder is 1.7M3 so that would equal 1700 Litres of gas which should be around 4 hours welding @ 7lpm. If you have been welding for 1 hour solid then that would be a quarter cylinder of gas. Have you verified that you are actually flowing 7LPM? The regulators designed for mig welding can be inconsistent at lower flow rates. I realise dollars are tight, but it will not take long to burn up a lot of dollars in gas if you are flowing too much. The bobbin type regulator and flow meters excel for low flow tig work. I would possibly set your flow more by ear, (it should feel/sound like someone gently blowing in your ear), rather than by the gauge due to the fact that I suspect your regulator is inaccurate, like many, at low flows. Use less gas in a shed with no breeze than if you were welding in a breezy area.
I would also echo what several others have posted. 2.4mm is the sweet spot for tungstens. They will reach down to handle 1.2mm but still handle welding 10mm ally. 3.2 handles the thick sections better, but won't reach down like 2.4mm. None of them are magic bullets though.
The beauty is that now you have a torch that you have options for. You can experiment with shrouds, tungsten sizes and even gas lenses if you wish and consumables are readily available and cheap.

Originally Posted by WelderMick

Looking better gazza,

Circled red bits look best to me.
gazza.jpg
With your fit up... which version are you doing?

Good:
good.PNG


Not so good (minimal penetration):
Not Good.PNG

i think the top picture in 1.6mm alloy will only give me more grief than i can handle, at the moment ive found a nice sweet spot with this new torch im able to get good penetration without melting thru or getting thin penetration marks on the other side that widen as i weld along, even tho this new torch is much making it much easier to weld this 1.6mm stuff im still having problems with the speed i move and the amount of filler im adding i think a pyrex cup might be the solution?

Originally Posted by Karl Robbers

That weld is much better than you were getting before. Always a bugger to weld over ground areas, so I reckon you probably had a bit of trouble there.
Just need to work on fusing both sides of the joint and getting more consistent with your travel and addition of filler material.
A D size argon cylinder is 1.7M3 so that would equal 1700 Litres of gas which should be around 4 hours welding @ 7lpm. If you have been welding for 1 hour solid then that would be a quarter cylinder of gas. Have you verified that you are actually flowing 7LPM? The regulators designed for mig welding can be inconsistent at lower flow rates. I realise dollars are tight, but it will not take long to burn up a lot of dollars in gas if you are flowing too much. The bobbin type regulator and flow meters excel for low flow tig work. I would possibly set your flow more by ear, (it should feel/sound like someone gently blowing in your ear), rather than by the gauge due to the fact that I suspect your regulator is inaccurate, like many, at low flows. Use less gas in a shed with no breeze than if you were welding in a breezy area.
I would also echo what several others have posted. 2.4mm is the sweet spot for tungstens. They will reach down to handle 1.2mm but still handle welding 10mm ally. 3.2 handles the thick sections better, but won't reach down like 2.4mm. None of them are magic bullets though.
The beauty is that now you have a torch that you have options for. You can experiment with shrouds, tungsten sizes and even gas lenses if you wish and consumables are readily available and cheap.

i actually think im contaminating the cut area with the jigsaw blade, there was one stip that i left welded this was 2 sections of metal cut by the shop i had only the start and end to weld up to finish that section off but it welded fine no contamination and a nice shiny bead, all the other sections ive cut with the jigsaw come out crap with black stuff all around it, im also using the flow meter in my picture

If that flow meter says 7LPM, then you should be good to go.
Welder Mick is right, that corner to corner joint is what you should be aiming for. 1.6mm is not a good way to start learning. 2.5 to 4mm would be much easier. Re contamination from jigsaw. You aren't using CRC, WD40 or such as a lubricant are you? The only lubricant I would use if I had to weld the cut area is metho from a spray bottle and even then only in 4mm+ thickness material. I've never had a contamination issue with jigsaw cut areas unless the blade had a lot of paint or grease built up on it. Use a coarse ish blade, you don't need or want a fine tooth metal blade for ally. A good basic rule for ally is, if it works on wood, it'll work on ally.
The only real advantage to a pyrex shroud is that they are see through, but, they are fragile. I don't really see it helping you much. Practice is what you need more than anything. The real problem with 1.6mm is that the movements are all the same as 2.5 or 3mm, but they have to happen faster and pauses are rewarded with holes melted. If you think that's bad, try welding the fins on an intercooler!
If you think about the game were you place your hand with fingers spread on a table, then stab a sharp knife between your fingers faster and faster. You never stab your hand while going slowly, only when going fast. So it is with welding thin sheet. The movements are all the same, just the speed at which they are made causes you to run off the rails a bit and lose coordination. Start with some 3 or 4mm and work down.

Originally Posted by Karl Robbers

If that flow meter says 7LPM, then you should be good to go.
Welder Mick is right, that corner to corner joint is what you should be aiming for. 1.6mm is not a good way to start learning. 2.5 to 4mm would be much easier. Re contamination from jigsaw. You aren't using CRC, WD40 or such as a lubricant are you? The only lubricant I would use if I had to weld the cut area is metho from a spray bottle and even then only in 4mm+ thickness material. I've never had a contamination issue with jigsaw cut areas unless the blade had a lot of paint or grease built up on it. Use a coarse ish blade, you don't need or want a fine tooth metal blade for ally. A good basic rule for ally is, if it works on wood, it'll work on ally.
The only real advantage to a pyrex shroud is that they are see through, but, they are fragile. I don't really see it helping you much. Practice is what you need more than anything. The real problem with 1.6mm is that the movements are all the same as 2.5 or 3mm, but they have to happen faster and pauses are rewarded with holes melted. If you think that's bad, try welding the fins on an intercooler!
If you think about the game were you place your hand with fingers spread on a table, then stab a sharp knife between your fingers faster and faster. You never stab your hand while going slowly, only when going fast. So it is with welding thin sheet. The movements are all the same, just the speed at which they are made causes you to run off the rails a bit and lose coordination. Start with some 3 or 4mm and work down.

nah no lubricant and ive only used the blade for cutting perspex also its a fine metal blade

the next job i do ill buy a whole sheet of 3mm ally

also about the tungsten any idea why mine isnt balling up? it keeps splintering after i sharpen it, once splintered it stays that way, im using the sanding disk to sharpen

Originally Posted by gazza2009au

nah no lubricant and ive only used the blade for cutting perspex also its a fine metal blade
There's your problem - Perspex contamination. On that subject. If you buy PVC coated ally and I would by preference, don't forget to peel the PVC back at least 50mm before you try to tack or weld the sheet.
the next job i do ill buy a whole sheet of 3mm ally
Don't forget that the most cost effective way to learn is often to go through the scrap bin at a sheet metal workshop and using their offcuts. Better to learn on scrap than an actual job.

also about the tungsten any idea why mine isnt balling up? it keeps splintering after i sharpen it, once splintered it stays that way, im using the sanding disk to sharpen

While a sanding disc will sort of do the job, they don't like tungstens much. A silicon carbide grinding wheel on a bench grinder is textbook for grinding tungsten unless you have a proper tungsten pointing machine, (never seen or used one of these in the flesh). You shouldn't need to sharpen your tungsten much for AC. Try leaving them square other than a slight chamfer if you desire, then striking an arc at 120 odd amps. You can strike the arc on a piece of 4MM+ steel if you want, it doesn't have to be ally. What type of tungsten are you using? I personally still use the good old Zirconiated for AC and Thoriated for DC. I only sharpen for AC if I am welding thin material, (sub 1.6mm), with a 2.4mm tungsten. On AC current, tungstens will spit and pop a bit if dipped in the puddle, but don't actually tend to full on splinter.

Originally Posted by Karl Robbers

While a sanding disc will sort of do the job, they don't like tungstens much. A silicon carbide grinding wheel on a bench grinder is textbook for grinding tungsten unless you have a proper tungsten pointing machine, (never seen or used one of these in the flesh). You shouldn't need to sharpen your tungsten much for AC. Try leaving them square other than a slight chamfer if you desire, then striking an arc at 120 odd amps. You can strike the arc on a piece of 4MM+ steel if you want, it doesn't have to be ally. What type of tungsten are you using? I personally still use the good old Zirconiated for AC and Thoriated for DC. I only sharpen for AC if I am welding thin material, (sub 1.6mm), with a 2.4mm tungsten. On AC current, tungstens will spit and pop a bit if dipped in the puddle, but don't actually tend to full on splinter.

im using the white tungsten 1.6mm

ahh so thats the problem all along me using the jigsaw to cut perspex bugger!

It catches the best of us sometimes Gazza.
White tungstens are Zirconiated so you are on the money there. Surprised it isn't balling up, particularly in 1.6mm size. Don't sweat it too much though, as long as you get a nice clean consistent arc who cares what shape the point is. I know the Hobart Tig I used to run, produced a very different size and shape ball than the Miller at the other end of the workshop and my Transtig different again. I've never met anyone who examined the ball on the end of my electrode, most prefer to look at the completed welds
You're making some really good progress here though. Using a coarser blade in your saw will be easier to cut with into the bargain.
I had a thought. I don't suppose you own a router? If you do, you could cut the sheet a bit oversize and then clamp a guide to the sheet and with a straight cutter machine the edges back nice and straight with your router, (TCT cutter of course). A circular saw with the correct blade works well too.
One of the most pleasant jobs I ever had was fabricating ally that came off a profile router. No square or measuring tape required hardly and perfect fit up every time.

Originally Posted by Karl Robbers

It catches the best of us sometimes Gazza.
White tungstens are Zirconiated so you are on the money there. Surprised it isn't balling up, particularly in 1.6mm size. Don't sweat it too much though, as long as you get a nice clean consistent arc who cares what shape the point is. I know the Hobart Tig I used to run, produced a very different size and shape ball than the Miller at the other end of the workshop and my Transtig different again. I've never met anyone who examined the ball on the end of my electrode, most prefer to look at the completed welds
You're making some really good progress here though. Using a coarser blade in your saw will be easier to cut with into the bargain.
I had a thought. I don't suppose you own a router? If you do, you could cut the sheet a bit oversize and then clamp a guide to the sheet and with a straight cutter machine the edges back nice and straight with your router, (TCT cutter of course). A circular saw with the correct blade works well too.
One of the most pleasant jobs I ever had was fabricating ally that came off a profile router. No square or measuring tape required hardly and perfect fit up every time.

nah mate i dont have a router i do have a circular saw but it doesnt cut inline with the notch on the front lol

i just finished welding my welds are not the best i found 7 leaks, 6 of those are along the bottom welds 1 is on the upper side of the bait tank ive marked each one so i can grind them down and reweld

Originally Posted by gazza2009au

nah mate i dont have a router i do have a circular saw but it doesnt cut inline with the notch on the front lol

Don't let that concern you too much. As long as it cuts parallel with the sole plate it's ok. If you clamp a guide such as a piece of box section on the sheet, the saw will run along that and you will get a nice straight cut that should fit up quite nicely, knock the burrs off with a file or sheet deburring tool such as this one D063 | Sheet Metal Burr Deburring Tool | machineryhouse.com.au. A fair bit faster than a jigsaw too, not that this really bothers you too much for what you are doing.
Before we had the guillotine at my last workplace that's how we did it.
The type of blade needed is a negative rake, triple chip blade. like these. Aluminium+ Series Blades - Tools - IRWIN TOOLS
Some food for thought anyway.
The leaks get less with experience, we used to compete at work. If you got a leak in a tank, you supplied the friday drinks.