the snooper
getting older by the day
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thought this may be of some use to people with a Dc only machine
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Richard.
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I wouldn't watch that twit if you paid me! It's nothing new that
Alu can be welded in DC to a degree but the two best methods I know of have big limitations to the point it's only worth doing as a one off get you out of trouble.
It can be done in DC- with a helium shield which aids a hotter arc for melting the oxide layer but it doesn't move the oxide layer so it's a very dirty looking weld or it can be done in DC + with big tungstens and low current which welds much cleaner but you put a lot of strain on the torch and parts for the very little current you put out. Ok for thin stuff.
Bet "I'm mr tig" proves me wrong mind. Plonker imho.
Alu can be welded in DC to a degree but the two best methods I know of have big limitations to the point it's only worth doing as a one off get you out of trouble.
It can be done in DC- with a helium shield which aids a hotter arc for melting the oxide layer but it doesn't move the oxide layer so it's a very dirty looking weld or it can be done in DC + with big tungstens and low current which welds much cleaner but you put a lot of strain on the torch and parts for the very little current you put out. Ok for thin stuff.
Bet "I'm mr tig" proves me wrong mind. Plonker imho.
the snooper
getting older by the day
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well I cant argue either way as I have never had a go with tig, just thought other people may not know its possible
Richard.
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Which is a fair point tbf
I think jody WTT does a couple too of Alu in DC - with helium.
Richard.
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The issue is with either suitable method it really only works at extreme ends of the scale.
I've had success results with DC + on a piece of 1-2mm plate at 50 amps with a 3.2 tungsten but any thicker and your pushing your consumables too far.
In DC - it also works but only on really thick lumps because you need the helium to boil out the oxide layer and because it's DC - with the aid of helium the penetration will be waaaaaaaay deeper than the same weld produced in AC with argon.
The plus side is you can get away with much smaller tungstens and there is no heat in electrode.
From my personal experience both methods are a bit of pig to strike up and arc stability on DC+ is less than ideal with low current been used in conjunction with a lump of rebar as a tungsten.
There is no middle ground really
2-6mm plate is an unsuitable range for either method imo which is where most single phase sets spend there lives.
I've had success results with DC + on a piece of 1-2mm plate at 50 amps with a 3.2 tungsten but any thicker and your pushing your consumables too far.
In DC - it also works but only on really thick lumps because you need the helium to boil out the oxide layer and because it's DC - with the aid of helium the penetration will be waaaaaaaay deeper than the same weld produced in AC with argon.
The plus side is you can get away with much smaller tungstens and there is no heat in electrode.
From my personal experience both methods are a bit of pig to strike up and arc stability on DC+ is less than ideal with low current been used in conjunction with a lump of rebar as a tungsten.
There is no middle ground really
2-6mm plate is an unsuitable range for either method imo which is where most single phase sets spend there lives.
