Newb buying advanced mig, Lincoln Invertec STT, good idea?

[magnusk750]

I'm offered a Lincoln Invertec STT with separate wire feed LN742. Type plate on the main unite says IEC 974-1 and max 225 A. I can have it for about the same money as an ordinary ca 200 -250 A compact MIG/MAG. I will probably use it mostly for ordinary welding of auto sheet metal and laymans constructions of mild steel. A table here, a fixture there, but of course it's kind of tempting to know it CAN do much more advanced stuff than that. I'm not very experienced, long time ago I welded quite a lot but with a small ESAB Miggy 125, then it got stolen and I've not had a welder in ten years. Seller is says he's tried it for auto sheet metal fabrication but didn't get the hang of it. He got it in a package deal with other welders for his auto repair shop and haven't used it much.

So, question is, will this be a tricky machine to use for those kind of tasks? Will I be better off withfor example an ESAB Origomig 200 A, Migatronic 183A or something like that?

 

[MoreWellie]

small point and you probably know this is but going by the plug this welder is three phase, do you have a suitable supply?

 

[magnusk750]

Yes I have, 3 ph 380 v is kind of standard in a workshop here.

 

[Richard.]

The lincoln stt machine was built for putting in fast roots in open root gaps on pipe. V down position . Very expensive machine.
Lincoln list price on the new one is just short of 10 grand.

 

[magnusk750]

Yep. That's why I want to know if it is also a capable allround welder for laymans mild steel welding? The price is not a problem, question is if I will do better with an 'ordinary' compact mig welder?

 

[Richard.]

Well it's not your average joe machine. These are bought usually by companies that specialise in big pipe welding. Answer is yes it will do more than what your basic compact will but it's wasted if it's not gonna be used for what it's for. If I was in your shoes and a wanted a decent mig and the stt was going very cheap I would buy the stt then sell it for what it's worth then buy a decent mig machine to suit what I needed and line my pockets with the difference .

 

[magnusk750]

Yes, I'm perfectly aware that it's overkill for average joe like me. On the other hand, I know I will not start welding big pipes, though, with a capable welder I might do other type of welding, aluminium, or whatever. Or, just enjoy a top notch machine?. Sell to earn a bob, well of course, but that's not why I'm, (perhaps) buying. I can also say that I have quite a journey to reach it, at least a days drive. Toghether, this is why I'm curious if it's a usable, and even good, as a overall mig, or is it more awkward, difficult to find the right settings? Not even possible, suitable, as an universal MIG?

 

[Richard.]

I've only used one for pipe roots once. Which although I believe that is it's intended purpose I cannot see any reason why it would not be great at all the other aspects of mig. From what I can remember it does not have a voltage control it sets it's self in accordance with your stick out to prevent burn through. It's been years since I used it. You should look up what lincoln themselves say about it and go from there

 

[Richard.]

Yes, I'm perfectly aware that it's overkill for average joe like me. On the other hand, I know I will not start welding big pipes, though, with a capable welder I might do other type of welding, aluminium, or whatever. Or, just enjoy a top notch machine?. Sell to earn a bob, well of course, but that's not why I'm, (perhaps) buying. I can also say that I have quite a journey to reach it, at least a days drive. Toghether, this is why I'm curious if it's a usable, and even good, as a overall mig, or is it more awkward, difficult to find the right settings? Not even possible, suitable, as an universal MIG?

Did u go for it

 

[magnusk750]

Soon, I hope. I'll report.

 

[Jim Davey]

They are brilliant on sheet steel, buttery smooth with almost no spatter, however you will need to spend some time getting the hang of setting it up right as it's not as straightforward as a modern synergic mig can be.

 

[wheresmejumper]

Very low spatter, low noise, fairly easy to get results on synergic in a short time, with lots of potential adjustment in manual mode for the future.
if its a good price go for it

 

[Kent]

I have to say you can have too much machine, yup if its cheap I should buy and then sell it on for a profit and get a set that more suits your needs. I think the seller gives us a clue

 

[magnusk750]

Bought it yesterday. Tried it, not on sheet metal but on a ca 5 mm bar, and felt like we started to get the hang of it. I'm quite excited. There's 1,2 mm wire and feed wheels on it now, no reg or gas bottle. I've to get the correct feed wheels, 0,8 or 0,6 wire, regulator, gas etc before I can start fettle with it at home. Probably will change the pistol too. Water cooled pistol on it now, quite clumsy and I won't use that much power that I really need it. According to seller it's modified with a standard coupling and shouldn't be a problem to fit another pistol.

 

[magnusk750]

Warming up an old thread. Yesterday, at last, I got the welder working. Set up with 0,8 wire and mix gas, but difficult to get the settings right on sheet metal. There are charts in the manual with sample settings, but in general, when I went by the chart it didn't burn the material, only produced 'birdshit' on the surface. Applied more current, but then again it burnt through very quickly. On thicker materials I could sometimes come to the buttery feel someone mentioned above.

Is there a defined way to achieve the right settings? On most mig welders there's only two parameters, current and wire feed. Here it's four, backgroud current, peak current, wire feed and hot start, difficult to know which one is wrong.