Hi all,

I recently recieved my new 200 Amp DC MMA/DC Tig welder by Magnum welders. It promptly arrived 2 days after purchasing online. This is despite me choosing the cheaper "standard" postage over the "express" which was a few dollars more.

All arrived well packed and in good order.

The unit itself looks quite well made and put together. The welding leads connect very positively with a type of bayonnet fitting which I assume is a type of industry standard now. My older AC welders just use a brass nut and bolt.

I have since tested this welder with some scrap steel and found that it produces a lovely bead and a stable arc with both GP and low hydrogen electrodes. However, I won't bore you with endless pictures of welding beads because I get the impression that even the cheapest welders can do this when knew.

I also tested the welder using my 3.5KVA generator. It was all a bit too much for it at the higher current settings but under about 120A it was actually not bad, even with low hydrogen. Indeed the instructions suggest a minimum of 7.5KVA generator. Previously if I tried to weld from the generator using my AC trnasformer welder, the poor governor on the generator would be all over the place and as a result I could never achieve a stable arc.

Next I did what I like to do with just about everything..... I took it apart.

While I have never owned an inverter DC welder and so have nothing to compare it to, I was pretty happy with the way it was put together.

All the parts came apart nicely. Nothing had to be forced or flexed to be removed. All the screw holes lined up nicely. Even the metal cover looked well made.

After I took the case off, a nice big heat sink running the full length of the unit and fed by a decent sized fan was the first thing I noticed.

I removed a couple of the clamps that hold the IGBT's onto the heatsink and noticed neatly applied heat sink compound under all the components. While Im not familiar with reputable brand names for these IGBT's these ones had no name on them so I assume they are just cheapies. Certainly no Toshiba to be found!

Being a budget model MMA/DC Tig, the front panel is a simple affair with a POT, an ammeter, toggle switch and overtemp/Duty cycle indicator. The front panel is neatly made and accurately punched out of steel. A nice touch is the threaded brass inserts molded into the plastic cover that it screws into rather than just self tappers into plastic.

Inside the cover you will find six capacitors in the rectifier section. While their value of 470 uF didn't hit me as being over the top, what I did notice is that they had printed on them "for welder". I didn't realise that there were specific caps used for welders but I guess it's nice that the desiners have gone to the trouble of using such.

All in all the unit itself looks to be reasonably well made. Certainly a reflection of it's 2 year warranty. At $350 plus delivery I think it represents good value for money for anyone wanting a DC arc welder and don't want a bargain basement model that may only last a couple of years.

Probably my biggest dissapointment with this welder are the leads. At 5M I am pretty happy with the length, I fail to get excited by the earth or electrode clamps. While both have copper on their connectors, the electrode holder just feels terrible. It's not a piece of equipment that feels nice to use. While It does do the job and I can't fault how it clamps the electrode, it just feels yuck!

As for the earth clamp, the spring is nice and tight but the flimsy piece of braided copper wire that connects the top and bottom parts of the clamp is see-through and does not look like it will last very long.

All in all I think I made the right choice. I really don't think I could get a much better welder for my $350. The electrode holder may well be a personal preference thing. I may end up replacing the clamps. Or, I may just use them until they fall apart!

Hope some people may find this helpful.

Simon



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