score of the season

[the fabricator]

me and dad recently took a trip to Bunnings to get some skirting boards. dads being dads he got caught up in a long conversation with a mate. so i went to have a look around and found the welders section. sitting there was a display model Transmig 135 by Cigweld with a big yellow sheet saying $300. needless to say i took it, $20 in consumables later and i have a little mig i can use where i can be bothered for tig

my best bargain

do i REALLY need agrosheild. or will argon do the trick?

[Grahame Collins]

The short answer is yes you really need Argoshield.

To elaborate further on the subject.
It has oxygen and Co2 gas components which give the welding arc some bite or penetration.

For general purpose purpose work I suggest something like Argoshield light or its equivalent.

There are a big range of shielding gases that are for specific materials and tasks which when used in industry for mass production are very cost effective,but in your case your jobs will vary.

I am sure someone will ask why you use straight Argon with tig and the answer is that the penetration is gained in the much slower travel speed of the tig.

The mig by comparison travels at a faster rate.

I don't think fluxcore (gasless )is an option for you as the machine DC output supply must be reversed for fluxcore and from memory this little Mig has not got this capacity.

I hope that answers your question

Grahame

[the fabricator]

its on fluxcore now, with reverse polarity and it is able to be switched. i ran the fluxcore roll out today so when i get solid wire i'll get argosheild light

25% CO2, 2-3% oxygen sound right?

[Edd]

No, there's significantly less CO2 when you add O2.

Common gas is 75/25, 80/20 or 85/15 % Ar/CO2

Better gas is around 93/5/2 % Ar/CO2/O2, which Argoshield Light is. Linde used to sell this under the name "Corgon 5/2"

There's also ones that are 95/5 Ar/O2, but I'm not quite sure of their purpose, maybe stainless.

Have a look at this comparison of different gases. (http://www.mig-welding.co.uk/welding-gas.htm)