Need help with 240 volt tig welder selection please

[sleepy]

I love the way you worked in the story about the Tits well done Sleepy

Back when I heard the story a female welder was as rare as male nurse, now anything goes what is the world coming to!!

[GMC]

These old EMF welders were good value, my father bought one like this long before I was born, its been in the family longer than I have! I used it for quite a few years when I first started but now its just a bench to hold up the radio and phone. Haven't been able to plug it in for many years now, decades even.
Yes they are 200 amps but the Miller inverter 200 I switched to was more powerful and has a smoother arc.
They are actually 2 phase-480 volts, they only use 2 of the 3 phase legs and this option can be found in some places that don't have 3 phase.
Those DC converters were sort after decades ago, I was going to buy one once but they were over a grand new and rarely came up for grabs, times change and DC welders are now as common as mud

[GMC]

You need AC to TIG alloy, as Sleepy says its to lift the oxides so you can create and control the weld pool.
When the Alternating current flows to the electrode it lifts the oxides and when it flows towards the work piece it creates the weld pool
Normally AC alternates 50 times a second (the electrical gurus here might know better than me), but the modern welders can vary higher and lower than this which creates different advantages when welding.
I find it hard to fathom how it can change so often every second but then I also find it hard to imagine how a four stroke valve can open and close 5000 times a minute

Zirconiated tungstens are the go for AC welding
Thoriated tungstens used to be the go for DC welding but the 2% of thorium in them has been deemed dangerous when grinding them so they are getting harder to find as Retailers/manufacturers now try to avoid them
Alternatives are now Lanthanated and Circoniated which I beleive can be used on both AC & DC
I have been using the Lanthanated for DC now for quite a few years but still use the Zirconiated for AC

Also note that you should reverse the polarity of you DC machine when you want to arc weld, this is due to the electrode flow, when TIG welding you want the workpiece to absorb the heat and save the non consumable electrode but when arc welding you want the consumable electrode to absorb the heat to melt into the workpiece.
Some modern machines can do this with a switch rather than physically swapping the leads over.

[Slakewell]

Have a nice 3 phase tig welder for sale if any one needs one.

[shelpi]

Only recently found out the application for DC aluminum welding, it is used for thick jobs as it penetrates the job extremely well with out distortion, can be used for critical welds and Xray tested to a very high standard, its not some thing I would be doing
please see the forum I was sent to on the subject   forum.weldingtipsandtricks.com  like I said ive been welding for years and just only found this out myself (just thought very interesting)

[80-85 husky]

what was the lady welders nickname???

[Mick D]

Mine had a seperate HF box for Alloy welding.. it was missing when I went to pick it up....   life is full of theives 

Mick, pretty sure I've got one of those boxes at my other house - you're welcome to it if you want it,
Pete.

That would be awesome thanks Pete 

[Mick D]

I have had a couple of looks at that welding forum you put up Shelpi,, lots of good stuff there, Thanks.

You too thanks Geoff and Sleepy,, I will be certainly reading all this over for supply choices etc when I start.

Cheers  

[Momus]

I started alloy tig welding about 40 years ago using one of these.
http://www.graysonline.com/lot/0004-5000686/engineering-and-toolmaking/sheet-metal-welder-emf-pilot-arc-6-5-kva-150-amps-415-volt-3-phase-po
Add says 150 amp but they are actually 200 amp, a few years after buying my first one I got a second and joined them together and had a 400 amp AC high frequency welder.
They were in service doing repairs on mainly Harley engine cases and heads up until about 5 years ago when I picked up a new 350 amp inverter machine that was made in China and it has worked well in that time.
I stopped doing the Harley shit just after buying the new welder as I just got sick of welding and dealing with the shops.

 A good 200 amp welder sounds like it will do all you want but the foot pedal are really only good if you can sit at a welding table, I have one with the new welder but hardly use it.
Someone was talking about filler rod earlier. You will need atleast 3 types if you are to play with bike stuff. I mainly use 5% silicon on cases as it is the lowest melting point, the 5% mag is the strongest and machines better but is more prone to cracking on cooling, pure magnesium also comes in handy but it is expensive and hard to get.
With the Gas. Boc do a deal with the D size[small] bottles where you pay $108 rental a year and get 1 free fill of gas a year. Bunning have it now as well with a $200 refundable deposit on the cylinder and no rental. I still pay the $240 year rental on the E size argon as I go through a bit and it is about half the price for the gas in the big bottles.

Good luck and do plenty of practise before doing your big fin head.

Valuable! thanks Sleepy
Your not going to believe this,,, I have one of those EMF "pilot Arcs" buried in the shed,,, did a lot of steel etc with it in the day, then bought it of my employer when we decommissioned the site. Still no 415v power at home though see if I can get close enough for a pic,,,

Started with an EMF as well. Great pie warmers.