In article ,
Bradford Chaucer wrote:

I am cnsidering a tig welder.

Price range?

My main interests are welding aluminum,
steel and stainless, in thicknesses up to 3/4 in, mostely repair and small
shop fabrication projects. I have a big-a**ed stick welder for the heavy
work on steel.



3/4" aluminum is not practical to TIG weld.
For aluminum heavier than 1/4" consider a MIG welder.
Much more efficient than TIG for heavy aluminum.


Questions:

1. The choices seem to be between the transformer welders and inverter
welders. I know that generally inverter types have lower duty cycle. Other
than that, are the as reliable?
Has there been a problem with blown power semiconductors??
Is the ability to weld (within the capacity of thre machine) similar
for transformer and inverter supplies?

The newest Inverters exceed any transformers in duty cycle and
efficiency.



2 I presume that if one tries to exceed the duty cycle for long, the
machine will trip out on overload/thermal protector... How does this effect
the weld in process?? Will an abrupt termination of the weld mid way
result in damage/ruination of the parts, or does one merely commence
welding again when the machine cools down?
Can one extend the duty cycle by adding a fan to cool the inverter
supply?


It is unlikely you will trip the breaker on a large inverter.


3 Some TIG welders claim that HF is not needed because they output square
wave power or other means to start the arc, Are the non-HF types as easy
to use/start as the traditional HF equipped ones?


Inverters don't really need continuous high freq for AC TIG.
They generate something that works just as well using capacitor
discharge high freq.

4. Almost all of my welding jobs would be of short duration - a couple of
minutes. Would a water cooled torch be needed or is air cooled sufficient


A 200 amp air cooled torch like a CK210 from CK Worldwide would work
just fine.



5. I have noticed some off brand TIG machines on Ebay, mostly inverter
types, i.e. an outfit called Smiley Tools which makes a combo
tig/Plasma/ARC unit typically providing 120 or 150 Amps to the Tig torch.
The unit looks like an inverter. There is a similar unit by MITECH. These
units sell for under $1000. Is this a strictly you get what you pay for
situation?? Has anyone out there seen or used these units? I presume that
they all are made in China or thereabouts.

Thank you in advance for your comments.

For the size of work you want to do a transformer will likely be more
affordable.

Look at the Syncrowave 350LX

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