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View Full Version : How many amps do I *really* need?



rlincolnh
31st Dec 2007, 03:43 PM
Hi All,

I'm contemplating buying a Mig welder. Never done any welding in my life, and it will only get very occasional use (few times per year, probably, although new ideas do seem to keep popping into my head). My requirements will be from thin (1/2/3 mm) fabrications (turned, milled parts onto bits of angle, etc) to frames of about 4mm WT square tube, with similar thickness brackets etc to be attached. I had been considering the Transmig 165, but my son-in-law (boilermaker, structual contractor, has just bought (another) 300-and-something Amp Lincoln, etc etc) says no, no, no, don't consider *anything* under 200A. You'll feel the difference, he says.

Now he's a good bloke, but I suspect he may be a bit like one of my electrical engineering lecturers of long ago who always used to 'round off to the nearest 10A'. In my work (electronics) I'm always fighting to save 1mA!

I get the idea of duty-cycle restrictions, but I wonder how much is that likely to affect my proposed work? e.g. the Transmig 165 is rated at 20% @ 150A. So how much (linear travel) 4mm work would I likely be doing in, say, a one-hour period? Not that time is all that important, but spending the whole afternoon doing something that should only take 15-30mins after lunch will probably start to get old fairly quickly.

Sure, I could get him to do the work for me, but I'm one of those guys who wants to do everything himself!

Never minding the price difference (Just Tools have the Transmig 165 for $880 incl GST, while the 200 and 220 work their way up towards $1500), the change in physical size and weight are a major concern for me.

So, does anyone have a comment?

Also, while S-I-L didn't actually turn his nose up at my mention of Transmig, he didn't give it any glowing endorsements either. More comments?

Roger

moose
31st Dec 2007, 03:58 PM
165 will be more than enough

DJ’s Timber
31st Dec 2007, 04:04 PM
For the sizes your quoting, the 165 will handle that with ease using standard wire with gas. If you start using it for gasless welding, that's where it will start to struggle, especially on long run times.

Brickie
31st Dec 2007, 04:12 PM
I just bought this (http://www.discountwelding.com.au/product_details.php?cPath=178&products_id=313) and am more than happy with it..

You will be struggling with 165 amps to weld much more than a couple of mm's thick.
Also, check out the duty cycle, at 165 amps the duty cycle would only be about 10%. ie, weld for 1 minute out of 10 minutes, not real good.. :doh:

Barry_White
31st Dec 2007, 06:06 PM
I have a BOC 175 that I have welded up to 10mm with and I find it quite adequate for what I do with it. For the average handyman that size is good enough. Since I bought it BOC have changed the amperage sizes slightly but not enough to make much difference.

aussiecolector
31st Dec 2007, 06:19 PM
165 amp will be flat out with the 2-3mm especially if you have a good run of vertical down. It will be very slow going with 4mm. Having said that if you are only doing small jobs of a couple of minutes welding at a time you may be happy with it.

rlincolnh
31st Dec 2007, 07:07 PM
Well, thanks guys, but your replies (and similar comments that I have seen elswhere) combined with equipment brochure specs still leave me wondering.

Brochures say 6, 7, 8, 9, 10 mm for machines in the 160A - 220/250A range.

Some people (e.g. Bazza) say they use small machines on thick material. Others, like Brickie, say that you won't get a decent fillet without high amps. (Similar un-solicited comment from son-in-law). All this being unrelated to duty cycle considerations.

What is the real story?

Roger

Barry_White
31st Dec 2007, 07:14 PM
If you are patient Grahame Collins will reply in the thread and you will get the real answer.

Brickie
31st Dec 2007, 07:31 PM
If you want to buy one machine buy the right machine that will do all the jobs you will ever need to do.

I think if you buy the 165 amp machine you will be disappointed later on.

Brickie
31st Dec 2007, 07:38 PM
but I suspect he may be a bit like one of my electrical engineering lecturers of long ago

I just read that bit again.

So why are you asking us, youre the one who should be telling us lot..:?

jmk89
31st Dec 2007, 07:40 PM
If you want to buy one machine buy the right machine that will do all the jobs you will ever need to do.

I think if you buy the 165 amp machine you will be disappointed later on.

I'm going to give exactly the opposite advice - because you can get access thru the SIL to the monster to handle the big jobs (even if you have to ask him to do it), get the 165 for the little domestic jobs you can do yourself. If it turns out that the 165 isn't up to a job, then go and eat some humble pie with SIL.

rlincolnh
1st Jan 2008, 01:50 PM
Thanks guys, useful comments.

Bazza - yeah, I've been waiting with bated breath for a dissertion from Grahame.

Brickie -
If you want to buy one machine buy the right machine that will do all the jobs you will ever need to do.

In an ideal world... As I said in my original post, it's not really so much a matter of money as size and weight. My garage is home to my wife's car, my car, a Bridgeport, a 13 x 40 lathe, a Puma 17K compressor, a beautiful 60-year-old English drill on its own bench, a work bench, a grinding bench, a couple of storage cupboards, and another 7' cabinet with all my brother's boating tools etc (he lives on his yacht, so I'm the work depot). It's like one of those puzzles where there is one spare slot and you have to shuffle all the other pieces through tortuous paths to find a solution:C

Brickie -
So why are you asking us, youre the one who should be telling us lot

When doing a power budget for a new design, my work sheet goes something like:
Device draws multi (or, gnash teeth, tens of) milliamps - figure how that part can be powered down most of the time, keep thinking/searching for a less power-hungry part.

Device draws tens to a few hundred microamps - ok, but let's not get too carried away

And finally, keep an eye on all the nanoamp leakages - the just keep on adding up

As you can see, anything that draws over an amp is HIGH POWER ENGINEERING:U. So welding is in the same class as base-load power stations in my book. I couldn't possibly presume to pass technical comment on the process. It's just my curiosity that keeps me asking why there is so much conflict between all the claims and counter-claims.

Grahame, where are you...

jmk89 - good, reasonable advice. But, damnit, I hate pie..

Roger

rlincolnh
1st Jan 2008, 02:02 PM
Sorry, I missed a response:

aussiecollector -
especially if you have a good run of vertical down

Remember, I know zip about welding. What's the significance of your comment? Why does direction/attitude come into it?

Thanks,

Roger

aussiecolector
1st Jan 2008, 02:14 PM
When you are doing vertical down you can turn up the welder and pore the metal on as there is less chance of blowing a hole

Brickie
1st Jan 2008, 02:22 PM
I went through this process a few months ago before settling on the machine I bought.

I went and talked to sellers of machines, told them what I wanted, listened to all the bullsheet, compared prices, etc.
Every seller will tell you a different story about the supposed power of the machines.

You can always turn the power down with a more powerful machine, but its a bit hard to turn it up with an underpowered one..

If you only want to weld very thin 1 to 2 mm stock, the machine you are thinking of may do the job, but honestly once you start you will want to weld more and more, and will find the machine underpowered.

Have some gravy with the pie, it helps it slip down a bit easier..:D

Brickie
1st Jan 2008, 02:24 PM
When you are doing vertical down you can turn up the welder and pore the metal on as there is less chance of blowing a hole

Vertical down is a crap welding technique (unless there is absolutely no other way to do the job), vertical up is a way better.

thesupervisor
1st Jan 2008, 02:45 PM
i would forget the mig go for a decent inverter stick welder you can weld all of your wants with a 160a machine
vertical up is the only way to performa structual weld thats a australian standard
vertical down is only recomended for very thin material eg 2mm down but i still go up

aussiecolector
1st Jan 2008, 07:03 PM
If you refer back to my first post I was talking about welding 2-3mm steel and didn't mention structural welding. There are many more kg's of weld put down vertical down than any other position. Any fabrication work including high pressure gas lines, all sheet work where possible and I have seen up to 50mm plate welded vertical down. The reason is when you have the amps and everything going for you you can put down about 3-5 times as much weld which has a much smoother finish which will be less likely to lead to fatigue cracking.

Now I am not talking about some important weld on some earthmoving equipment or the weld that holds some highrise up or a repair to something that wasn't built strong enough to begin with. I'm also not talking about trying to weld 4mm with only 165 amps.

Any one who welds especially with a mig who doesn't do some vertical down welding isn't getting the most out of their welder.

Brickie
1st Jan 2008, 07:22 PM
There are many more kg's of weld put down vertical down than any other position. Any fabrication work including high pressure gas lines, all sheet work where possible and I have seen up to 50mm plate welded vertical down.

So vertical down is preferred to flat welding? I dont think so.[/quote]


The reason is when you have the amps and everything going for you you can put down about 3-5 times as much weld

But no penetration


which has a much smoother finish which will be less likely to lead to fatigue cracking.

Right..:rolleyes:


Now I am not talking about some important weld on some earthmoving equipment or the weld that holds some highrise up or a repair to something that wasn't built strong enough to begin with.

Obviously.


Any one who welds especially with a mig who doesn't do some vertical down welding isn't getting the most out of their welder.

Ill try it next time Im bored with welds that have penetration and hold the job together.

Not wishing to hijack this fine thread.

But.
Not once did the vert down weld rate any significant mention when I did Pressure Plate at the School of Mines in Ballarat many years ago.

It rated a mention, and it was the last resort weld to do if there is no other way to weld something. :D

Brickie
1st Jan 2008, 07:57 PM
This says it all really.. (http://www.woodworkforums.com/showthread.php?t=62780)

Grahame Collins
1st Jan 2008, 11:12 PM
There are many more kg's of weld put down vertical down than any other position. Any fabrication work including high pressure gas lines, all sheet work where possible and I have seen up to 50mm plate welded vertical down.
Any one who welds especially with a mig who doesn't do some vertical down welding isn't getting the most out of their welder.

aussiecolector

I believe you are very,very wrong in much of what you have written. I cannot let it pass as I believe there is a potential safety issue here.
I don't think I missed the "its ok to do vertical down bits" when reading AS 2885 Pipelines Gas and Liquid Petroleum and the SAA 1697 Pipeline Code.

Perhaps your shops had a different WPS than the rest of us.

It is a Change in Essential Variables.Big NO NO without a re qualification of the procedure.

Some open root pass work certainly can be done vertical down.Fill and cover butt passes in pressure pipeline can not.The simple reason is the a vertical down pass (by virtue of the nature of molten metal to obey the laws of gravity) has to be achieved with a fairly quick technique. Downwards travel with a large fluid weld pool atypical of a fill or cover pass means the operator needs to go like the clappers- result-too fast for adequate penetration.

Amperage alone does not provide penetration.Travel speed and wire stick out has a bearing on it as well .
Seeing such procedures carried doesn't account for validity of the practice -it indicates that the shops involved in this practice were probably cowboy outfits. Such places are usually shortlived as their work will come back to them eventually and bite them on the bum.
Try a comparison etch test of vertical down coupons and vertical up coupons. There will be a discernible difference in penetration depths.I have performed many such tests as an Accredited Testing Officer AS testing for AS 1796 Welding Certificates in Queensland.

To make a general statement like you have is misleading at best. We have some dam fine people here who are amateur welders. There is potential here for those people to utilise this information in the wrong context and get into some real strife.

There are limited situations where vertical down is acceptable such as sheet metal where the very limited penetration can be used to advantage or certain root run passes in open root pipe and plate work were again a minimum level of penetration is required.

This a pretty good forum and I for one don't wish to see it dragged down with one of our members involved in liturgation because a weld failed and some one got hurt or even worse, killed.

By all means fellow forum members, do some research on this topic and just don't take my word for it.
regards
Grahame

Grahame Collins
2nd Jan 2008, 07:45 AM
Hi Rodger,
I sincerely apologize to you as I got distracted elsewhere and should have replied to you first as the originator of the thread.

Regarding your intended purchase of the Cigweld machine. We all start out with the best intentions (of what we want to achieve ),but somewhere along the line things have a way of changing. I would surmise as has been the case of nearly everyone I know that down the track a bit ,you will find find the machine is not big enough.


Its a heap of cash to drop on a machine so your first choice had better be a good one.

A point not mentioned was the spool size. The smaller spool makes for less weight and better portability,but when it comes to cost you are paying considerably more for your wire per kilo.

Many of us will want to experiment with the different metals available and eventually you may find that you want to weld aluminium. This little machine won't do it. Aluminium on these machines requires a small OD wire so it will burn efficiently with the smaller max amps available.In turn the smaller wire size lead to wire drive snarls.

Having said that, if your mind is made up, at least go an try you machine at the dealers as once you paid for it it is hard to return because you do not like it..Also check out what accessories come with it particularly the regulator. Some don't supply a reg as part of the start up kit -it is an extra.

In answer to this <So how much (linear travel) 4mm work would I likely be doing in, say, a one-hour period?> at 200mms / minute -your 20% duty factor maybe 10 meters if you're a robot and don't stop .For the rest of rest of us-maybe 6 or 7 meters per hour.

I hope this helps
Grahame

Fossil
2nd Jan 2008, 09:23 AM
Any fabrication work including high pressure gas lines, all sheet work where possible and I have seen up to 50mm plate welded vertical down.

I worked on the SA-NSW border run of this countries biggest gas pipeline for 3mnths as a pipeline welder (Internal). That is another story, but the info that you posted, as quoted above is B.S. :rolleyes:

I realise it has already been covered by others, but when I saw your post I felt I had to reply anyway.

Fossil.

rlincolnh
3rd Jan 2008, 12:27 AM
Grahame and Brickie, thanks for your comments. When I get beaten over the head often enough, with a big enough stick, I eventually get the idea. So it seems that less than 200A is out. It was never carved in stone, just seemed particularly desirable. And I take your point about the low-amps/thin-wire/feed-snarls for Ali work. I knew about all three points, but hadn't made that connection. Thanks also for the linear-travel indication.

I looked at the Weldmaster that Brickie got, and the WIA, Liquid Arc, and Transmig, all in the 220 - 250A range. The Miller, Esab, Lincoln, etc are too rich altogether for me.

Hmmm... SIL has just been around here, so I discussed it further with him. He said 220A, and if I need to do anything bigger I can use his shop gear. I was a bit surprised when he steered me off the Liquid Arc range, although he also said their wire and rods are second-to-none. So right now I am looking at the Weldmaster Mig220 which, at $1595 incl GST, seems like the best bang for my buck.

Again, I would like to thank everyone for their input... but... I still haven't seen an explanation of why some people assert that they can do satisfactory (large-fillet?) work on thick material with smaller machines:;. Is it that it is, in fact, possible, but very slow, or ...???

I feel that there must be a story lurking in there somewhere. One thing's for sure, I have a lot of learning to do.

Regards,

Roger

Brickie
3rd Jan 2008, 04:58 PM
So right now I am looking at the Weldmaster Mig220 which, at $1595 incl GST, seems like the best bang for my buck.

Dont forget that those machines come without the hand piece which is another $140 for a 3M binzel style.



Again, I would like to thank everyone for their input... but... I still haven't seen an explanation of why some people assert that they can do satisfactory (large-fillet?) work on thick material with smaller machines:;. Is it that it is, in fact, possible, but very slow, or ...???


I think the claim is either a beat up or they pre heat, if you have to pre heat you need a torch which is more expense.
Maybe its the manufacturers claims that are exaggerated?

You wont be disappointed with the Weldmaster I am more than happy with mine.
If you buy from the same mob I got mine from, again you will be very happy with the service, it took 3 days from ordering to get to my place in Melbourne and they are in Campbelltown NSW..:2tsup::2tsup::2tsup:

rlincolnh
4th Jan 2008, 12:10 AM
Yeah, discountwelding seem to have the best price. Thanks for pointing out the missing gun - I was blinded by the price, and the 40% @ 220A rating, which seems pretty good for a single-phase machine.

When I look at the gun page, it starts all over again - more styles than I could poke a stick at! I presume (??) that there is some degree of standardization of the connector so that several different types could be used an the one machine. So what does it come down to when selecting a gun?

Roger

Grahame Collins
4th Jan 2008, 12:59 PM
Roger
There are few criteria for mig gun selection,

Brands-
Tweco, Bernard and Binzel were the big names now copied by all and sundry.The main difference being noticeable to me in the contact tip and nozzle shroud mountings. For instance I like a nozzle that can pull straight off for cleaning and a 1/4 turn cam lock fit contact tip. Others have screw in fittings.I can't remember who had what, other than the Bernard had the trigger on top which I hated.

Ergonomics
Some welders like the trigger on top,some on the bottom,some triggers have a latch to lock on for continuous welding.

Amperage
A 250 amp capacity is more than ample for your 200 amp machine

Attachment
Two types , that I am aware off
Euro connection - All in one ,quick connect and disconnect.
Standard spigot fittings,slow,fiddly and old came out when the arc was built.Gas ,wire feed and electricals are all 4 separate connections.

Length of cable
Some ,not all, are available with varied cable lengths to suit operator requirements.

This is off the top of my head ,if I remember more ,I will post, but you should be able to select something from that lot and asking the right questions to the vendor.

Cheers
Grahame

Riley
4th Jan 2008, 04:06 PM
Hi everyone been lurking for a while and decided to post eventually.

"My requirements will be from thin (1/2/3 mm) fabrications (turned, milled parts onto bits of angle, etc) to frames of about 4mm WT square tube, with similar thickness brackets etc to be attached."

I do agree with all said re the size. (No to vertical up) You may well get by with 140-180 but it wont be long before you regret not getting 200+.
With Migs my preferences lie with Lincolns, SAF's and Arc Liquide's .
With guns I swapped all my welders over to Kempi's with the large ribbed liner as its all aluminium mig welding and with 1.0mm and 1.2mm wire its no problems with the 4.5m lead even with twists.

If you have no experience in welding and want to go down to 1.0mm wall , have you considered a Tig? especially if its all stainless or mild steel (AC tigs for ally is another story). Much better for thin wall and you have the option to Stick weld also. A 160 Essetti will just handle a 4.0mm rod in stick.
My preferences there are Essetti's for small and Lincoln's for bigger AC ones.
With little experience in Mig welding 1.0mm stuff will end in tears.:~


Edit: I just noticed I said :"(No to vertical up)" Sorry that was a mistake vert. down is the easiest way to have no penetration and inclusion etc.

rlincolnh
4th Jan 2008, 05:23 PM
Thanks Grahame, that gives me something to go on.

Riley, I take your point about no-experience/1mm-walls. I must say that 1mm is at the bottom of the list for most of the work that I envisage. I hope that by the time I get there, I will have a reasonable amount of experience with (mostly) 3mm. I have seen some beautiful smaller work done with tig, and I expect that I will give it a go at some stage. Ease of learning was one of the driving forces in my choice of mig as the first step into welding.

What was behind your comment <(AC tigs for ally is another story)>? Was it just with regard to the high cost of a good AC tig, or was there more to it?

Maybe a subject for a new thread, but just what is the great difficulty with tig work? On the face of it, it appears completely analogous to ordinary oxy-acetylene work, yet any mention of it brings an instant response along the lines of 'oh, yes, difficult though, yes, very hard...'.

Roger

Riley
4th Jan 2008, 05:51 PM
Thanks Grahame, that gives me something to go on.

Riley, I take your point about no-experience/1mm-walls. I must say that 1mm is at the bottom of the list for most of the work that I envisage. I hope that by the time I get there, I will have a reasonable amount of experience with (mostly) 3mm. I have seen some beautiful smaller work done with tig, and I expect that I will give it a go at some stage. Ease of learning was one of the driving forces in my choice of mig as the first step into welding.


IMHO a Mig is not the most appropriate machine for 1 and 2 mm material.


What was behind your comment <(AC tigs for ally is another story)>? Was it just with regard to the high cost of a good AC tig, or was there more to it?


To have a AC tig you are either looking at a inverter .The pluses are size and 240v, minuses cost. Or a 3 phase if non inverter type .You will find you will tend to max out at 4-5mm wall on straight Argon 1/4" at a pinch with He/Ar mix with a 180amp Ac Tig on Aluminium.Over 200amps you are paying big money for a good one.


Maybe a subject for a new thread, but just what is the great difficulty with tig work? On the face of it, it appears completely analogous to ordinary oxy-acetylene work, yet any mention of it brings an instant response along the lines of 'oh, yes, difficult though, yes, very hard...'.

Roger

The jump from Oxy to tig is a small one .As with mig Tig is all practice. With beginners I do believe you have more awareness of penetration.

boilermaker
21st Dec 2008, 08:58 PM
Well, thanks guys, but your replies (and similar comments that I have seen elswhere) combined with equipment brochure specs still leave me wondering.

Brochures say 6, 7, 8, 9, 10 mm for machines in the 160A - 220/250A range.

Some people (e.g. Bazza) say they use small machines on thick material. Others, like Brickie, say that you won't get a decent fillet without high amps. (Similar un-solicited comment from son-in-law). All this being unrelated to duty cycle considerations.

What is the real story?

Roger

I wouldn't buy less than a 150 amp... As most home welders rarely work with steel more than 6mm thick a 165 to 200 is ideal. I prefer Lincoln or WIA as brands like SIP have many plastic components that need replacing often.

As to wire.. save bottle gas hire and usea quality flux core wire .. either Lincoln or CIG 0.9 mm wire with a 1.2mm liner.

To weld thick steel with a small mig just means multiple runs to get the weld fillet size... a 170amp using 0.9 wire may need 3 runs for a 6mm fillet.. in comparison a 450 amp machine would give you a clean 6mm fillet but needs 3 runs to do a 10mm fillet weld. For thicker material ensure you have a good clean weld prep.

Grahame Collins
22nd Dec 2008, 06:46 AM
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

boilermaker
22nd Dec 2008, 09:07 PM
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/Catalog/equipmentdatasheet.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.

Grahame Collins
23rd Dec 2008, 12:10 AM
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

boilermaker
23rd Dec 2008, 07:49 PM
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.

simso
29th Dec 2008, 12:21 AM
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

patrolos
14th Jun 2009, 08:51 AM
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.

Grahame Collins
14th Jun 2009, 09:47 AM
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

patrolos
14th Jun 2009, 02:53 PM
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?

soundman
15th Jun 2009, 01:20 PM
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 :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

NewLou
15th Jun 2009, 06:53 PM
Gidday :D

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! :D:D:D

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 :2tsup:

patrolos
16th Jun 2009, 05:33 PM
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?

patrolos
28th Jun 2009, 11:27 AM
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

pipeclay
28th Jun 2009, 12:25 PM
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.

patrolos
28th Jun 2009, 04:38 PM
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

Grahame Collins
28th Jun 2009, 07:30 PM
The whole point in the development of the spool gun was to overcome the near 2 metres of soft wire being pushed ahead of the drive wheels.

This is the cause of all the grief.


If the existing set up runs steel wire why not use it it?
Grahame

patrolos
28th Jun 2009, 07:37 PM
Thanx Grahame, but will it run steel?

Grahame Collins
28th Jun 2009, 09:32 PM
I have no idea.In any case if you wanted to do so I think you will find yourself winding wire on your own spool.

Given that the unit is dedicated to welding aluminium there is room for things to go wrong.

Its a lot of fluffing around for little obvious return.Do the instructions give any indication of being able to run steel?

Grahame

soundman
28th Jun 2009, 11:32 PM
my understanding of the lincon spool gun thig is that the spool gun replaces the standard handpiece and hose set up.

to change from steel to aly you would just untread the steel filler wire from the drive gear, uncouple the standard gun and couple up the spool gun.

that is the beauty of the system, you don;t need to clean anything or change liners.

or is the problem that you didn't purchase a standard handpiece with the unit?

cheers

patrolos
29th Jun 2009, 07:13 AM
my understanding of the lincon spool gun thig is that the spool gun replaces the standard handpiece and hose set up.

to change from steel to aly you would just untread the steel filler wire from the drive gear, uncouple the standard gun and couple up the spool gun.

that is the beauty of the system, you don;t need to clean anything or change liners.

or is the problem that you didn't purchase a standard handpiece with the unit?

cheers

No. I have both guns. I won't be using it often, so rather than swapping guns over thought it would be easyer to swap spools.

soundman
29th Jun 2009, 12:11 PM
One thing you need to be very aware of is the need to keep the feed path uncontaminated when using aluminium.

So unless you want to clean out the spool gun and possibly change some items in the feed path...using steel and aluminium in the same gun isn't all that good an idea.

As I said all you should need to do is wind back the steel and change the handpieces, which looks very easy....I've been lookig at one of those machines too.

Apart from the wire feed issues one of the bigest advantages is you don't have to clean or change liners going from steel to ally and back....you just change the handpieces.

you should be able to leave the spool gun fully loaded and ready to go and the spool of steel wire in place in the main unit.

cheers