Thread: How many amps do I *really* need?

Hi guys,
I have not had my eye on the ball for a while, so to speak ,sorry!

Sooner or later you will want to attempt something heavier /larger and /or aluminium.

Trust me, for general you want something bigger than 160 amp or so .You can still weld small wall thickness.

If going welding aluminium, 180 is your absolute minimum as there are issues in metal transfer mode at settings below this amp figure.


Don't forget you will also need a 15 amp power supply.

Cheers.


Ps for the guys who are looking for the lesson 3 in mig welding,It will be a little while.

I lost an external drive with all my stuff on it and will have to re write it.bugger!

Grahame

Originally Posted by Grahame Collins

Hi guys,

Sooner or later you will want to attempt something heavier /larger and /or aluminium.

Trust me, for general you want something bigger than 160 amp or so .You can still weld small wall thickness.

If going welding aluminium, 180 is your absolute minimum as there are issues in metal transfer mode at settings below this amp figure.


Don't forget you will also need a 15 amp power supply.

Cheers.


Grahame

I disagree with the 180 amp figure.. all depends on what you plan to do. I have found for most home projects, business and construction worksites my 170 has been perfect, be it for mild steel, stainless or aluminium. If you are going to get into regular heavy construction then a three phase welder will be needed. If it's a one off then take it to your local steel fabrication shop.


I don't mean to advertise the Lincoln but under $1k, a 3 year warranty, all parts available in Australia and durability I cannot falter, I wouldn't buy anything else . I have had mine since 1993 and it has easily done over 1000 hrs work, dropped from 2mtrs, dragged through mud, left on in the rain and not once gone in for repairs and handled everything I have attempted.
Nowdays it has been replaced by the Lincoln sp180.. http://www.mylincolnelectric.com/Cat...t.aspx?p=59619

I don't know about the 180 but my 170 easily runs off a 10 amp plug (with adaptor extension lead) as it pulls @ 11.3 amps ...just have to make sure not too many appliances are on.

180 amps is the figure that aluminium runs well at spray deposition mode .It will run below that but in short arc mode and aluminium does not like short arc The deposit looks like crap..

Don't take may word for ,go and do some research on it.The Lincoln procedure handbook is a good place to start.

In my experience as a teacher I find people in general have trouble with the multi pass fillets and don't get adequate penetration into the base plate in a HV position.

In respect of your Lincoln 170 amp aren't you comparing an inverter unit with a std transformer unit?If the Lincoln is a inverter yes 170 amps no probs as the inverter is not wasting 10% of the current as a heat loss like a transformer does.I looked at Lincoln when I was was buying my Kemmpi and in hindsight am sorry I did not go Lincoln

Again this is another reason to run a bigger hotter single bead on heavier plate towards 10mm.

As a trained boilermaker it should be second nature to read and set up your mig, but lay people mostly do not have that experience and it can take a while to get some up to speed.

Having certified candidates in AS 1976 Cert 8 I have broken many test plates and know well where the defects are most likely to occur.

Cheers
Grahame

Grahame,

You made a point that lay people do not have the experience.. so true.. which brings me to my point that most lay people will not be tackling heavy fabrication jobs. At best they may weld a 8mm plate onto 2.5/3mm RHS for a trailer coupling or fabricate some 4mm pipe or rhs posts with a 6-10mm base plate as examples.

As to aluminium welding I doubt many a lay person would go to the expense of setting themselves up beyond small projects or repair jobs on bullbars and tinnies, where the welds will be cleaned up with a grinder.


I am a qualified boilermaker, have held certs in pressure pipe and plate, have had welds pass and fail all testing methods. I have also had my own business and dealt with people whom have gone " Gee! welding looks easy.. I'll buy a welder and build my own........" and then called me to fix their mistakes and finish the job. Not once have I seen anyone with a welder plugged in at home attempt fabricating to the realms you speak of. Even on country properties with combine harvesters or cattle runs have I seen anything made from heavy plate/RHS/pipe by the occupants... they leave those jobs to the experts.

I fully comprehend what you are conveying, but people looking to these forums for advice won't be fabricating warehouse structures,cement silos or repairing ball mills, they will most likely be fabricating pergolas, outdoor furniture or repairing an old HG sedan. We can come down to their level, they can't come up to ours without proper training.

Not having read all the replys I may be simply repeating whats already been said, but either way. 1,2,3mm 130amps will breeze through it 4,5,6 160-185 amp units will breeze through it, 130 amp unit will require a triple lay down for 4,5,6mm thickness's. 7,8,9,10 = 215 amp unit will breeze through it 160 amp will require double lay downs.

Biggest thing however is not to get a unit that has switches for thicknesses eg the el cheapo bunnings stuff etc, if you ever want to weld thin stuff like on a car you need to be able to have control of your amps in increments of ideally 5, the cheap units will simply blow holes in your car panels but will work fine for 2-4mm thickness's

Hi guys.
I know this is an old thread but I also have been looking for a "domestic" welder.
I'm planning to do some body work on my old Patrol and build and aluminium slide-on camper. I'm planning to build the camper out of Aluminium tubing then I'll sheet it up. The welds don't need to be neat but they will need to be strong because I'll be doing a bit of off road driving.
I have been looking at the CIG 165 unit and a few of the other cheapies but somehow I don't feel comfortable. Their guns seem a little flimsy.
I did like the Lincoln 180 but I noticed on their web site that they say ".....• Spool Gun Ready – add the optional Magnum® 100SG spool gun for reliable operation at the high wire feed speeds aluminum welding demands. No expensive outboard modules required.
Would I need this Spool gun or can I get away with the standard gun? The optional spool gun costs $400.

Originally Posted by patrolos

I'm planning to do some body work on my old Patrol and build and aluminium slide-on camper. I'm planning to build the camper out of Aluminium tubing then I'll sheet it up.
]Would I need this Spool gun or can I get away with the standard gun? The optional spool gun costs $400.[/COLOR][/SIZE][/FONT]

Until you have tried to weld aluminium with a standard gun and cable, you do not, yet, understand the real meaning of frustration.
Within the meaning of welding the unit will weld but only for a very short time , and thats what the sales priks don't bother to tell you,as follows.

The first time you allow a slight kink in the cable or a bit a bit of foreign matter sticks in the cable liner,the wire will form a snarl at the wire drives.

The ratio of weld to stop and repair repair is about 1 to 10.Yep! Stop disassemble gun cable, clear the snarl and begin again.

You are trying to push a couple of meters of very soft,SMALL DIAMETER wire through A LONG tube. If there is any impediment to its progress it jams,but the wire drives will keep forcing that wire ,but not down the liner.

Alternatives are to do surgery on the std gun cable and drastically reduce its length and thereby reduce its friction resistance . I have done that on a workshop mig but not a little home one. You are also dealing with a very small diameter wire - read weak and soft that is yet more inclined to fold up at the drives.

In contrast a spool gun only needs to push the wire a few mms to the nozzle ,not metres.The down side is that on a cost to weight ratio the spool replacements are very expensive.

That,s whyI would recommend a spool gun as the only other alternative, a push pull gun won,t fit your rig easily and is double the price of the whole out fit- maybe $2000 -have not priced them in years.

Others may not agree ,but thats my opinion

Cheers'
Grahame

Ahhhh!
I used to work in a bull bar factory many moons ago.
I wasn't a welder but I did try my hand a few times.
I remember I was forever calling the repair guys in to fix the guns. When I mention to the sales reps today about how often we repaired our gusn in the past they all tell me that it is not an issue. They tell me that the reason that our tools were always breakinmg down was because the welders didn't treat their tools with respect.
I think they just want to sell me their machines.

Is there a particular machine that you would recomend for someone like me who will probably only use it for a couple of projects?

I'm another on thinking about a mig some time in the near future.

Like many others I have arc and oxy as well, so I'm looking at the mig for the lighter stuff, that both the oxy and the stick have issues with.

Big brother (the pro welder in the family) is trying to talk me out of it but he is an absolute god with a stick welder, he did his time when mig and tig were only for the rich or elite.

Unfrtunately I am not that good with stick....there is this "weld, chip, grind and re-weld cycle" for me with stick, then there is the OH NO big hole when you over cook with the stick then the weld and grind cycle gets 10 times worse and with oxy there is the heat and distortion issue, I love oxy but there is always the distortion issue and it asnt all that fast.

So I am thinking about the mig for the >1 sheet 2,3 mm rhs and angle that you can make almost anything out of and may be some sheet metal work.
For any heavier stuff firing up the old "easywelder" is fine.
I've been told my stick work would improve considerably with an inverter stick, but I think the mig is a better proposition.....lets face it no one is going to give me a cracker for the old " easywelder".

I have looked at the lincon unit with the accessory spool gun, but mmmmm it is still a bit pricey and I seem to think the spools on it are still pretty small.

I hear what has been said about inverter V choke bassed migs, the issue would have to be the same for stick....the inverters seem to do more with less current, are more consistent, produce closer to their stated current AND produce more output from less input current.

Now this is where it gets all very fuzzy and complicated.

How much current is needed to do effective welds on what thicknesses OR possibly more realisticly what thickness will what machines weld effectivey?

I do understand that different welds need different amounts of current.

lets call the flat downhand weld the nominal point, because that is the simplest and easiest weld.

How much more current is required for vertical up, V welds and god forbid vertical down?

How much variability is there in the actual welding capacity of similarly rated machines?

I have been told that hand piece selection can be a bit of an issue. Bigger hand pieces use a lot more gass. Do smaller hand pieces do better small work? Do smaller hand pieces struggle with heavier work.

I have been told that you realy arent all that far ahead of a stick using flux coated wire in a mig because you are back to chipping slag. Is this true.

The smaller migs are attractive to me because you have to drag it arround the job due to a limited hand piece cable. I dont have this issue with the stick because I have a set of long heavy cables. Yeh I know that the serious shops have the mig on a gantry... but that wont happen at my place.
Am I missing something.

I have a couple of mates with mig's. One baught a cheapie that had wire feed problems from day one. Another has a big old commercial unit and a smaller cheaper ( midrange cheapie), he rarely uses the big fella, another has a big 3 phase job with remote head unit on a gantry... but he has to bring everything to the unit to work. Big brother has a mig that he hardly ever uses because he says stick is much less fiddle, but he is a mistro with a stick.
I can see that everybody has different needs and views.

Oh how well do those lincon hand spool attachments work?


so many questions.

cheers

Gidday

Honestly guys your wasting your money buying a Mig for home/hobby use. I'd go so far as to guess after the first 12 months your rigs will be lucky to get used more than half a dozen times a year!!!

IF and only if your a mad car/bike/truck/automotive enthusiast constantly doing cars and what not up................ there just might be an argument for a Mig if not you'd be doing your self a favor by passing them buy.

I'm in the camp that reckons your much better off learning how to stick n Tig Weld N a little 180 AMp Tig/Stick inverter in my honest opinion will give you the most versatile cost effective rig on the market today!

Learning to weld properly requires constant practice and application So A couple a years worth of night courses at TAFE are well worth considering.

If you persist and persevere with stick and Tig the benefits of effectively learning these 'DARK ARTS' are boundless and you'll get a lot more Bang for your buck and develop some really cool skills which some will truely consider godlike!

Ive been working in a Fab shop for a while now and would never consider buying myself a Mig................... Its 1 tool ive decided i'll never need

However if your into furniture making and incorporating metals like copper n brass into your own slant on contemporary furniture then your Tig rig suddenly becomes worth its weight in gold

Regardless of the path you choose ENJOY!

Regards Lou

I saw an Awelco 170 today for $650. Are they any good?
The sales guy said it's made in Italy. Is that a good thing?

Originally Posted by Grahame Collins

Until you have tried to weld aluminium with a standard gun and cable, you do not, yet, understand the real meaning of frustration.
.................................In contrast a spool gun only needs to push the wire a few mms to the nozzle ,not metres.The down side is that on a cost to weight ratio the spool replacements are very expensive.

That,s whyI would recommend a spool gun .............

OK. OK. I did it already
I got a Lincoln 180C with a spool gun.
I was reading the instructions and there is no mention about steel welding with the spool gun.
Can I mothball my standard gun and only use the spool gun as it would be much easier to swap spools than guns when alternating between metals?
Thanx Mate

I dont think it would a useful exercise if it was possable,im not sure if you can do it.
As it is at the moment the Spool gun takes .5 Kilo rolls of Ali I think,the cost of .5 Kilo rolls of wire would be fairly expensive in there on right as well as not being able to get much of a run for the amount of wire.

I'm not concerened about the cost of steel wire because I won't be doing much steel welding. It's just for the odd bit here and there. I'm mainly going to be using alli.
I