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Duncanstives
10-17-2007, 02:00 PM
I know there are a ton of other topics so hopefully no one will kill me for making another but I have a couple of questions which are not answered elsewhere:

1. My shop is in a barn with no electricity available. I have got a crappy 2.5kw generator but it is only 120. Is it in you guys opinion possible to MIG weld a tube frame buggy with a 120 welder? This also leads me to my next question:

2. Anyone know how much current these things pull FROM THE WALL? I have seen references to 300 amps or 90 amps or whatever but I am unsure of the voltage that the welding occures at. I know a 240 welder certainly is not drawing 300 amps at 240 from the outlet (do they even MAKE breakers for residential use that big?!... LOL). Watts law tells me my generator can supply like 20 amps (2.5kw @ 120v continious=20 amps... 3.5kw peak). This SHOULD be ok cause a typical 120 outlet is rates at 15A so I would assume welders are designed not to draw more than that?

3. A final question on an unrelated note: My co-workers tell me it will be possible to teach myself to mig weld with a couple of pointers from them and a few scrap pieces of metal (obviously my skill level will improve with expirience like anything else) but right now I pretty much know nothing so... Aside from the welder itself I know I need a mask and thats pretty much it... Can someone give me a rundown of everything I will need so I can get it all next time I go on a shopping spree? Suggestions of exact models for would be REALLY appeciated if only so I can look them up and check them out for myself and kind of compare.

THANKS!

Skyline
10-17-2007, 03:23 PM
I just went through the process of buying a welder, and I can tell you a couple of things that will help:

---The welding output of a given welder is not the same as what it draws from the wall. My 250 amp welder pulls 45 amps or so at full power.

---Newer welders that use inverter technology use less input for a given output. My previous welder took 90A at 220v to produce the same 250A output, and that was a machine less than 10years old.

---More voltage will require less amps.

---A 110v welder will do for tube...not ideal, but it will do if you go slow. You'll start to have trouble when you want to weld anything thicker. 3/16" thick steel is probably the limit unless you do multiple passes.

Take a close look at the Miller web site. Not only does it have full technical brochures for each unit they sell, but you can also find tutorials on welding. If you do stick to a 110v mig machine, I think you will need just about the most powerfull 110 machine you can find. Plan on also buying a helmet, gloves, wire, and a tank for shielding gas.

phillyzj
10-22-2007, 04:20 PM
I just went through the process of buying a welder, and I can tell you a couple of things that will help:

---The welding output of a given welder is not the same as what it draws from the wall. My 250 amp welder pulls 45 amps or so at full power.

---Newer welders that use inverter technology use less input for a given output. My previous welder took 90A at 220v to produce the same 250A output, and that was a machine less than 10years old.

---More voltage will require less amps.

---A 110v welder will do for tube...not ideal, but it will do if you go slow. You'll start to have trouble when you want to weld anything thicker. 3/16" thick steel is probably the limit unless you do multiple passes.

Take a close look at the Miller web site. Not only does it have full technical brochures for each unit they sell, but you can also find tutorials on welding. If you do stick to a 110v mig machine, I think you will need just about the most powerfull 110 machine you can find. Plan on also buying a helmet, gloves, wire, and a tank for shielding gas.

I agree with this ^

A lincoln sp135 would probably work for what want to do. they work alright, but really don't penetrate over 3/16" well at all.

I know you have the 2500 watt generator, but you might want to look into a more powerful one, I see 5kw generators for not a whole lot of money. I just started using an Hobart 210, man what a machine compared to my old Lincoln sp135! I am glad I didn't have to buy it though, haha.

Duncanstives
10-22-2007, 04:47 PM
Wow... For some reason this topic was not showing any replies :confused:

Anyway... Thanks for the tips guys... I have some 1/4 parts that will need to be done so it looks like I will have to figure something else out... I know we have a 220 powered welder at work I can use for thing I can carry in... But I cannot get the whole vehicle in here.

Hmm...

phillyzj
10-22-2007, 04:49 PM
Wow... For some reason this topic was not showing any replies :confused:

Anyway... Thanks for the tips guys... I have some 1/4 parts that will need to be done so it looks like I will have to figure something else out... I know we have a 220 powered welder at work I can use for thing I can carry in... But I cannot get the whole vehicle in here.

Hmm...

If you don't mind multiple passes or converting the welder to flux core, you should be able to handle the 1/4" parts that you need to weld.

Duncanstives
10-22-2007, 04:55 PM
Yeah but there is no way I am going to be able to do that with just 20 amps... And the generators breaker will trip if I draw more than that... Hell with a 7 amp angle grinder and a couple amp shop light the thing sounds pretty loaded down.

phillyzj
10-22-2007, 10:07 PM
Yeah but there is no way I am going to be able to do that with just 20 amps... And the generators breaker will trip if I draw more than that... Hell with a 7 amp angle grinder and a couple amp shop light the thing sounds pretty loaded down.

It shouldn't take any more current than running mig on the same settings, i wouldn't think. i ran one on a 15A circuit and it was ok but it would blow the breaker occasionally, but seemed to work.