Lincoln's STT wire feed

[tailshaft56]

Anybody familiar with Lincoln's STT. Vo-tech has a couple of them and thought I Might take one for a spin if I enroll in the upcoming MIG Class. Instructor says they are a bear to get the setting right but are very sweet once they are dialed in.

Dennis

[TRG-42]

Hi Tailshaft, there are many types of STTs

The stand alone units are the Invertec STT and STT II . These units can be hard to set up if you are not familiar with them. The best is figure out your application and call Lincoln. There is a ton of application data for these machines

The reason STT is confusing is everything you know about MIG you might as well forget because it violates the most fundamental aspect of MIG:

In MIG, Current varies with WFS - if you turn up the wire feed speed current goes up

In STT ( not a CV or true CC machine ) your WFS is independant of current.

This is why people get thrown for a loop with STT. They are use to WFS and Voltage ( as all other MIGs ) but now you have WFS, Background Amps, PEak Amps, and Tailout . There is NO voltage control

Fortunately if your machine is a Power Wave 455 STT , the its way easier because the Power Wave is fully synergic. Once you tell the machine what material ( steel , stainless etc ), wire size, and gas it chooses all the others to put you in the ballpark

The latest generation of Power Wave 455M / STT has synergic but oddly enough they ALSO have non-synergic . If the machines are these M models make sure you are not in the non-synergic modes.

BTW , STT is the most amazing short arc you will ever use !