TIG: would you trade min amps for max amps, or vise versa?

[dogma]

I'm on the fence between ordering a 255EXT (250A) and a 350EXT (350A), as the cost difference on AMZ is currently $550. I've already got a MIG machine at home so I'd like to try to end up with only TIG box.

The 255EXT is dual voltage (which is nice to have but not a requirement) and goes lower on the amps: 3A DC / 5A AC vs 5A DC / 10A AC . The 350EXT has a 30A higher 60% duty cycle and, obviously, higher max amps. The 350EXT also has slightly higher max voltage. I suppose the 350EXT probably has higher startup inrush current, which might be an issue on a generator (not a concern for me). The 350EXT comes with 18 & 26 torches instead of 20 & 9; I expect those will be promptly replaced either way anyways.

Perhaps a way to look at value is in terms of $/A.

255EXT - $9
350EXT - $8

I do occasionally want to weld 1/2" SS and mild steel plate but most of my projects are in the sheet to 1/4" plate range. Ignoring cost, if you could have only one, would you choose the lower minimum amps or the higher max amps?

 

[dieselshadow]

Lower amps for me. If you are welding big projects, more than likely you won't want a TIG for those unless you you were wanting to use it in stick mode.

 

[dogma]

Lower amps for me. If you are welding big projects, more than likely you won't want a TIG for those unless you you were wanting to use it in stick mode.

How often do you use < 10A? I'm having trouble coming up with a use-case.

 

[Holescreek]

Just a tip on purchasing. Save yourself the sales tax by getting your best price on Amazon or elsewhere then call Everlast direct. The sales people match whatever price you find including free shipping. In my case I saved about $150 in sales tax. The sales guys I talked to said they have so many different sales/incentives they have a hard time keeping track of them all.

 

[Uglydog]

If you do big aluminum then you might especially want the max amps.
Watch the duty cycle %.

Daryl
MN

 

[dogma]

If you do big aluminum then you might especially want the max amps.
Watch the duty cycle %.

One of the things that attracted me to this series was a video weld.com posted on doing thick aluminum with the 325EXT.

The only reason I'm not considering the 325EXT as well is that something must be different with the DC power supply, it says not to use it with 6010 rod.

 

[bss1]

From a practical perspective, I don't see any advantage of a machine that will go down to 5 amps vs 10 amps on the bottom end. Therefore, is the real question here should you spend $550 more for an additional 100 amps on the top end?

If so, then I agree with ugly dog, the larger machine with 350 amps would be handy for thick aluminum.

 

[brino]

but most of my projects are in the sheet to 1/4" plate range.

I use the "rule of thumb" of 1A per thou. thickness of material (for steel).
If you really need to do thin sheet, then the low-end amps are important.

On the high side 1/4" = 0.250, so by the "rule of thumb" you want 250A, right at the 255EXT max.

Of course, backer plates/chill plates can also help with thin material.

-brino

 

[bss1]

I guess I should have quantified my definition of practical. I consider 26 ga some pretty thin sheet metal. At .018 thickness and the formula mentioned above, that would require about 18 amps which is greater than the 10 amp minimum specified for the 350 amp machine. Therefore, if you think your usage will include welding more sheet thinner than 32 gauge (.0097") than you would larger stuff like 1/4"+ thick plate, then you may want to consider the smaller machine. To me the odds of needing to weld things on the larger end of this range would exceed my needs on the lower end.

I have a dynasty 200 which I think goes down to 1 amp. However in the almost ten years of owning it I don't recall having ever utilized a setting of less than 20 amps. In contrast, there have been times in which I have wished for more top end. YMMV

 

[DaveD]

One thing to consider is the higher the amperage, that you actually use, is going to crossover into the water cooled touch arena if you are going to do a lot of high amperage welding.

Go over and see what Jody has for info at weldingtipsandtricks.com. He has all kinds of tig, Mig, stick info.

Personally I wouldn't look for the lowest bidder/seller and would stick with Miller or Lincoln. You only cry once about he price.