MIG inverter vs Transformer?

[Mendeljef]

Can anyone say how MIG inverters compare to classic transformer type welders nowadays? I know a few years ago inverters were supposed to be less reliable, would be damaged easier and were more expensive to service and repair. But does this still hold true today? And how different is the welding? I'm asking because I want to buy a new machine and these are my options: Lorch pro 170 basic (1000 €) or Thermal Arc fabricator 181 (1000 €) or One Welding 200 (800€).
Though I do have some experience with Stick welding, I'm new to MIG welding. The welder is intended for hobby use and some semi professional jobs in construction: mainly sheet metal, furniture and light constructions. Also a reasonable amount of aluminium and Stainless steel welding. MIG use only, for stick and TIG I have a Fronius transpocket.

Here's a look at the machines: (web pages are not from the shop where I buy)

http://www.one-welding.be/index.php...&category_id=8&option=com_virtuemart&Itemid=1

http://store.cyberweld.com/tharcfa18miw.html

http://www.waspsupplies.com/lorch-m...chine--email--ring-for-latest-deals-858-p.asp

They come from a decent, reputed shop nearby , the vendor being very helpfull. The One Welding is a noname machine he adopted as his house brand. The Lorch is a demo model from the shop, it is 3 moths old and has been used about 30 hours, hence the 300 € reduction on the normal price. The fabricator is new out of the box. All machines come with full 2 or 3 year warranty. What I’m mainly intersted in is to know if there are considerable differences in welding techniques or possibilities; or machine quality.

 

[Angusdog]

I have only owned two machines, a Telwin BiMax 150A transformer MIG which was replaced with a Mitech 160A inverter MIG. The inverter seems much smoother and easier to weld but the main difference is infinitely variable wire feed and voltage so I can dial it in closer for welding thin panel steel. In other words, I much prefer my new inverter.

 

[matt1978]

This topic has been discussed before, try the search engine.

Inverters are definitely more portable so it depends on how much you plan on moving it about or taking out on site.

 

[matt1978]

Wire speed is infinitely variable on all machines, inverter or transformer!

The general consensus from the last time it was discussed was that a "good" quality European made Transformer machine was better value than a run of the mill Chinese cheaply made inverter.

Inverters do offer more control on voltage selection but if it's a comparably low amperage output machine anyway (eg less than 200) then this is not really a consideration.

I think the main deciding criteria should be on how movable and portable you need it to be. Inverters will always score higher in that instance.

 

[Wedg1e]

The problem with most (if not all) inverter-type designs, whether it's welding sets, mains generators, x-ray generators, switched-mode power supplies etc., is that the designers often start with the semiconductor manufacturers' data sheets for some power device and design a theroetically perfect circuit around it that takes no account of real-world conditions like back-e.m.f, heat and so on and THEN go on to specify the rest of the components to be barely up to the job. So these equipments tend to start working fine but give them a few hundred/ thousand/tens of thermal cycles, add in some electrical spikes through poor suppression and pop, another piece of kit that generally isn't worth fixing because they are so cheap (relatively speaking) to start with.
Give me lots of copper in a transformer any day (as long as I don't have to carry it around - otherwise, as said, inverter is always going to be preferable).
That said, big triacs, thyristors and so on are getting harder to come by than they were a few years ago: when I needed one for my Oxford 300 there was only one UK supplier that could get me one at a (semi) realistic price and quick delivery. There was some American Ebay comedian who wanted six dollars for the part... and 95 dollars to freight it. I paid Technical Arc's £38 with as much good grace as I could muster

 

[Mendeljef]

Movability is an issue here, so think I'll much prefer the 35 lb of the Fabricator over the 145 lb Lorch.

 

[matt1978]

You've answered your own question then