Thread: Aluminium welding examples

113 views and no guesses or comments?

Bottom is zirconiated top is thoriated. According to the salesmen the zirconiated should be the way to go. As you can see from these beads there is very little difference between the two beads using the different electrodes. Further welds I have performed since this day have mirrored these results.

Im my experience Thoriated is a great all round electrode.

I will put up some photos of various lap and butt welds if people are interested. However if people prefer to dicuss theory and hypotheticals and not real life examples then I wont waste my time.

just not knowledgeable enough to comment on the differences but happy to look at any further pics

Can you use these sticks in a normal stick welder? ie 50 Hz

No they were done with a TIG

Good work and keep up the practise. Like me, you're getting a crater at the finish. Add bit more filler at that point.

Originally Posted by 19brendan81

Bottom is zirconiated top is thoriated. According to the salesmen the zirconiated should be the way to go.

Im my experience Thoriated is a great all round electrode.

We used to teach A-Z ,ie Aluminium - Zirconated , Thoriated- sTeel.

In regards to thoriated electrodes they have probably found favour with new operators due to ease of starting and a current carrying capacity higher than the zirconated type.

Thoriated rods are touted as being radioactive but according to the Australian Atomic energy mob you would need to grind up the entire rod and inhale the dust to receive just 3 times the annual average background dose.

Thoriated can be used in the DCEN mode but they put a lot of heat into the parent metal.I don't do a lot of aluminium ,but my idea of it is that miniumum heat inputs are better than max.

Cheers
Grahame

Originally Posted by 19brendan81

Ok here is a photo of some of my welds that I have been meaning to get up on here for ages (see attachment). Ideally id take another photo with less glare in it, but we'd probably have to wait another few months for that to happen, so this will have to do for now.

I did these welds to experiment with my welder (TokenTools Inv200). You can adjust the AC balance from 20hz to 100hz, and thats what I did here. On the left of each bead you can see what frequency I did the weld with. On the bottom right of the piece was the amperage I used.

My favourite is 95amps, 100hz. It was a nicely proportioned bead. The 105amps beads seemed a bit flat, but the 60hz one was probably my second favourite bead. I didnt like any of the 85amp beads, it was definately too cold.

In all amperages, penetration increased with frequency. All of these welds were done with 2.4mm .8% Zirconiated tungstens, and 2.4mm filler rod.

The very bottom piece is two welds I did out of interest, one was with 2% thoriated tungsten, the other with ..8% Zirconiated. Anyone care to guess which is which?

my fav would be 95ampx100hz,for what its worth my exp as a boilermaker is that thoriated is not to be used on alloy

Hi Graham, Thanks for that info on the radioactivity of thoriated electrodes. I have heard people complain about the risk of using them and im glad the info you have provided suggests that the risk is minimal, especially for a hobby welder.

It doesnt bother me having to switch between electrodes as I own both types and its really not that hard to do. However I did find it interesting to note that the bead I put down with thoriated was pretty much identical to the one I put down with zirconiated. Im sure industry have their reasons for suggesting zirconiated for alloy, but as a punter who welds for fun and to make stuff around the house...if I was out of zirconiated and I had a job I needed to do id use my thoriated without worrying.

I do notice the zirconiated balls better though.

I'll do some joins. Welding on flat plate is all well and good, but joining metal is what its all about really.

Hi all,
I have used various tungsten electrodes as Grahame has described – thoriated for steel/stainless and zirconiated on aluminium at Tafe on a variety of machines (the best being a Kemppi 3 phase). At home I have been using 2% ceriated for all metal types, no need to change electrodes. Ceriated apparently have some better qualities like "better current carrying capacity; longer electrode life expectancy; better starting characteristics; greater resistance to contamination; produce a more stable arc; and reduced risk of tungsten inclusions contaminating the weld." (Theory & Practice of GTAW SA Davies, 1991, Harcourt Brace Jovanovich Group (Aust) P/L) - incidentally this guy wrote the Tafe manuals we used in NSW.
I'll see if I can find some links to some free stuff I found on the web (from reputable sources )
Regards, Richard

Here are some links.
Miller - Resources - TIG Handbook
http://www.millerwelds.com/pdf/gtawbook.pdf
http://www.diamondground.com/HowtoPrepareElectrodes.pdf
http://www.diamondground.com/Guidebook0105.pdfhttp://www.diamondground.com/Guidebook0105.pdf
The Tungsten Electrode Experts - Diamond Ground Products
NB: Americans use different colour coding.
I'll see what else I can find.
Richard

Thanks Richard,

I guess my point is, as evidenced by the two welds above, that all the resources on the web can say all they want about which tungstens to use in various situations, but when the result is that the bead between a thoriated tungsten and a zirconiated tungsten is identical....who cares? Does the average punter need to buy 3 or 4 different types of Tungsten? I very much doubt it.

Of course, someone who works in industry building aeroplanes or something might want to use the correct tungsten for the job as a wing falling off a plane due to tungsten contamination in a weld, is slightly more worrying than the aluminium shelf I made for my greenhouse cracking due to said contamination.

Brendan

Morning all,

Something that is occurring to me is that Brendan is using his thoriated tungsten on an inverter machine and yet I know from past experinces that this should not be so.

My experiences mainly were at TAFE where the welders were then,the venerable Miller CY50- bulky units about the size and weight of a medium domestic refrigerator.They are /were AC/DC rectified traansformer units.

My observations were that students who used thoriated tungstens on those old machines often had problems with splitting of the tungsten and subsequent parent metal contimination..

I suspect that the current breed of inverters produce an altered set of welding variables that allow the use of these thoriated tungstens on AC mode without the afore mentioned problems.

Or is it, I wonder that tungstens have been manufactured to a better standard that avoids the old problems?

Somewhere on the net I do recall reading where one of the Yank gurus espoused using a thoriated electrode.He even had his welds x rayed to prove his point.

In a way,everyone is correct. If it works with out problems, hey! go for it.

I would point out however that the method of sharpening I have seen else where is wrong.

This method is by tapering the tungsten either on the side of the wheel or the face but with the grind lines circumfrential to long axis.

The grind lines need to be parallel to the long axis. If they are not is has a bad effect on current flow, believe it or not.

Your tungsten axis needs to be square to the (bench) grinder and twisted in the fingers & tapered at about.2.5 to 3 diameters.

A happy new year to all
Cheers
Grahame

Your probably right Grahame, some of that stuff on the miller TIG welding handbook differentiates between electrode selection for modern square wave machines, and older transformer machines. So perhaps my inverter is more forgiving, hence my success.

What I find amazing is that in the case of lanthanated, adding 1% of the stuff to pure tungsten increases the current carrying capacity of the electrode by 50%! Whod have thought such a small addition could make such a big difference.

I grind my electrodes as you describe Grahame. There is one guy on the net who swears this is unnecessary, but everyone else says to do it this way....so I do. Its not that hard and it seems to work for me.

Brendan

P.S happy new year!