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Marc
6th Jul 2007, 07:38 PM
I wonder if we have a resident welding guru that can answer a few question.

I am an ex blacksmith with the emphasis on ex who has burned many tons of sticks a long time ago when MIG and TIG were a mysterious machine only used to build planes..
Now I fancy to do some blacksmithing wrought iron again 30 years later and the hobby 140 amp arc welder I have gathering dust in a corner of the workshop has no appeal after having used three phase DC industrial welders with a smoooth arc.

So ... here comes the question. I have some tools I really don't need like a Bosh Brute breaker I used once 3 years ago worth some 3k new I am told, may get half that.
Ok I am getting at it ...In short...Mig or Tig ?

I have heard all the prises for the easy of use of the MIG yet when I have probably lost practice I am sure I can regain it so lack of skill does not scare me. Also the MIG is supposed to have a penetration problem and need for different shield gases for different metals. Don't fancy to hvae more than one bottle and use it once a month if that.

TIG I hear is supposed to be slow? only one gas, no spatter and prices look like are close to the mig.
One thing that confuses me when I read specs on the Lincoln web site for example...they have some monstrosities weighting 200k and other slim called Inverters...and both do the same job?
What's the difference besides the weight?

I will be welding the usual steel flat bar, L round etc. Occasionally some thick bastards and also like to know I can weld aluminium and SS thinner than one can venture with a stick.

Any ideas very appreciated.
Regards
Marc

DJ’s Timber
6th Jul 2007, 08:05 PM
If ya mainly welding black steel, I would stick with a MIG, I have both and the TIG can weld black steel but is slow and is really not suited for heavy stuff. Also to weld Aluminium with TIG you need to have DC Negative/Positive and AC and a new machine could set you back 5k.

Never had probs with penetration with the MIG, just really a matter of getting the settings right and using the right argon mix.

Grahame Collins
6th Jul 2007, 08:56 PM
TIG I hear is supposed to be slow?
monstrosities weighting 200k and other slim called Inverters...and both do the same job?
What's the difference besides the weight?


Tig Slow? In general about the same as oxy welding.

The difference between the monster machines and inverters ?
The solid state electronics of the inverter change the frequency of the input power from 50 Hz to multi thousands of Hz.This allows all sorts of useful manipulation of the arc characteristics and the huge savings in weight. In addition the operator gets more usable power (arc force ) as it is no longer lost as heat from the transformer.

If you want to go AC/DC to take advantage of AC for Ali welding you will need around $5K. If you don't need Ali then a DC inverter comes in much cheaper.
The difference between welding transformer vs inverter is chalk and cheese. Go and try before you buy.
With the Tig you get two processes,Tig and DC stick

Avoid bargains on Ebay unless they are very well known known brands with the appropriate warranty.

Welcome to the mob
Grahame

Scotty690
7th Jul 2007, 04:54 AM
I just bought a UNI TIG from a local toolshop as the price was right, 200 amp AC/DC pulse tig, I just couldnt justify paying 4 or 5 times the price for the Miller Dynasty I had my eye on. I too was sceptical of the Chinese origin but with a one year warranty it looked better.
Its copped a workout this last few weeks, I was impressed with the job it did. Ive never welded Alloy before, this unit made it easy to learn.

Ive seen the same tig on ebay for a similar price with no backup, I like to know I can take it back to the shop for warranty repair though.

Scott

Grahame Collins
7th Jul 2007, 08:19 AM
Guys,
The purchase of electronic welding equipment can be a trap for young players. There is more than just the issue of the warranty.
Longevity, spare parts availability, repairers with the experience of that brand and model are all factors that kick into play on the day after the warranty expires.

On a copper wound transformer model welder it doesn’t matter overly much as they are straight forward to repair. Inverter welders are a very different proposition altogether.

Inverters generate high frequency current. High frequency current is dynamite on circuit boards and componentry. The reason is in the environment the average machine is exposed to and somewhere, sometime ,it will ingest metallic grinding dust. Circuit boards do not suffer metallic dust and HF for too long

You can see where I am going with this of course .Its a recipe for the blue smoke. Once the blue smoke is let out of the machine it can be difficult and expensive to put it back.

That’s when you need a very good diagnostic electrician who is well versed in circuit board failure and access to a readily available supply of spare parts.

I see all this on a regular basis because my better half works at an agency where there is a 10x 4 meter space on the floor covered in welders awaiting parts. The better brands have the parts here in Australia , You may only have to wait a month for the parts and the leccy to work his way through the pile.

Availability of a n experienced repairer is a major issue in itself. This particular electrician has always worked on welders. As an example you can a name a welder part ,usually on a Lincoln machine and Andrew can quote the part number.

Why have I written all this? So some one does not have to spend a couple of grand and wind up in two years with a box of fused electrical circuits that no can, or wants fix.

Rant over
Gets down off his soapbox ,dusts it off, picks it up and wanders off into crowd.
Grahame

Marc
7th Jul 2007, 07:04 PM
Ha ha Graham, I hear/read you.

Inverter, is cheaper but all electronic so buy a Lincoln or buy a lemon.
Transformer Tig, no problem.
What do you think of THIS (http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&ih=012&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=220127852934&rd=1&rd=1) little one?

So it comes down to price. Clearly I wouldn't buy a $5ooo welder to weld a sculpture or a gate once a month. I will stay well under 2k better if 1500.

So what do you recommend to a melancholic ex blacksmith?

Fossil
8th Jul 2007, 11:02 AM
If it were me, I would "stick" with the welder you have, or mabey get a better stick welder new or at auction or whatever. For welding steel, as long as you ensure that you have:

Very good power
Decent quality appropriate type, and dry electrodes
Good set of leads etc

Then stick is great IMO.

Anyway.... just my opinion.

tomhowell
8th Jul 2007, 09:21 PM
Hi Marc

I'm not a guru, actually just a fitter who has done a little bit of welding.

What I can tell you is that I agree with Fossil.
Stick is very versatile.

But I have just bought a new Stick welder which also does TIG.

Chinese? Yes
Solidstate? Yes
Light as a feather & small? yes
Good welds? YEAH BABY!
Tig on Mild steel & Stainless? Yes
Tig on Aluminium? No

Price with Tig torch & regulator? $754 inc GST

That's what I know about that.

Tom

Marc
9th Jul 2007, 07:50 PM
OK, things are getting clearer now.

Stick welding with a transformer, current is AC, results are poor. Cheap machine, unless you burn it it will last a long time.
Motor driven DC stick welder, fond memories, expensive, no one has one, 3 phase.
DC only inverters. Electronic, light, DC current smooth start and little splatter, can do TIG work on steel, easy to brake, expensive to fix.
AC/DC inverters expensive, good for steel and aluminium.

How am I doing so far?

I've seen an italian 170 amp single phase inverter DC only for $1500
A chineese 160 amp DC only for 550.
200 amp Lincoln DConly for 2200
200 amp AC/DC Riland (US..so they say) 800.
200 amp Lincoln AC/DC $5000 :o

Grahame Collins
9th Jul 2007, 10:37 PM
Marc,
I have no idea at all about a "Riland" machine. I have never heard of them until I saw your link.By now you would have researched this brand on the net.The lack of hits should tell you something about it.

I stand by my previous comments about buying welding machines. Like the old saying says "If it looks too good to be true, it usually is".With some thigs you can get away with buying the cheapy.

Sadly solid state welding machines aren't one of them.Sure the machine has parts and back up.Three years down the track out of warranty,what will a mother board cost when it loses its blue smoke? I should not be surprised if the replacement board cost exceeds the purchase price of the new machine.

Don't rush into a purchase yet.Also don't discount a good second hand machine .Remember that 3 phase can be wired back to single phase in many cases.

regards

Grahame

Wild Dingo
10th Jul 2007, 02:34 AM
Having just bought a welder... thread hereabouts somewhere :roll: I initially went with a arc job but ended up changing it up to a mig... still I cant comment on how good it is as the friggin rain has stopped me going anywhere near the thing so far

BUT!! Having said that... I looked at the cheeper brands available but thought whats the best known Aussie brand of welder? whats the most reliable? whats the best for accessing spares and such?... and the answer was... CIG... so thats what I got

I dont know about you but for 1300 it has all the qualities that I think Im ever going to need... is light portable (sorta in an arnie swazzanager way) and looks the goods so far everyone Ive spoken to about it or shown it to has commented that its one of the best on the market... so Im pretty confident that it is a bloody good one... oh and the cruncher for me? CIG have service centres all over the place! no delays no extreme travel no extreme costs to "return to base" straight down to the nearest CIG centre and bobs yer uncle :2tsup:

Now... Heuy ol fella how about just one damned week of fine weather to dry this friggin place out enough so I can get it down nearer the power source (house) to give it a friggin whirl if you please! :;

pcal
14th Jul 2007, 12:52 AM
My 10c worth... Bought myself a gasless mig several years ago now. CIG "Wirewasp". Best thing I ever did. Hadn't used any welder at all for many years previously (right back to stick and oxy welding at high school), and got myself up to acceptable standard in no time.

Being gasless, the wire is a bit dearer, but that is mitigated by no bottle rentals or refills at all, and the fact that the wire will last longer in storage than the bare wire for a gas mig (so you can buy it cheaper in bulk). There are a couple of varieties of wire to suit different metals, but to my knowledge alloys are a no go zone. (Tried to repair a piece of cast alluminium for Dad once - just blew it to pieces!). Also, the quality of finish is better than for a stick but isn't quite as good as with a gas mig or tig. But that's what chipping hammers and wire brushes are for isn't it? A bit of "anti-spatter" spray before you start helps out too.

I've done gates, frames, many many brackets, all the decorative stuff along Mum and Dad's verandas, pot plant hangers, even a weather vain. That's not even to count all the repairs to broken stuff from hand tools to car seats.

All in all, it's been a great investment.

Pcal

yogie
14th Jul 2007, 07:49 PM
The best way to go is a mig, can do anything in mildsteel, S/S. I own the migmag 200C, a great little machine, handles 6mm easy peasy, can do 10 mm but two passes thanks...:D
check them out, cost me 1100 bucks, runs the 5kg roll only, no worries about the 9kg getting all crappy due to not enough use, but dont use the .5kg rolls, too dear and too small.

wello
15th Jul 2007, 07:40 PM
Mig would be your best bet I have MIG TIG and Stick here at home the mig gets the most use
I brought a boc 250r which is a rebadged kemppi will weld 1/2 in a single past no worrys
50743

Marc
15th Jul 2007, 08:48 PM
So it's either stick with stick, or MIG.
Mmm...
I did some work with my old 140A today :doh: ...not very pretty I must say, I lost my touch a bit. Seem to get some decent runs with 2.5 mm sticks but the 3.25 is too much for the little thing. Aah, were is my rotary 3phase DC? Must be in welders heaven by now.

Saw an add in the trading post for a lincoln 255. The guy says he bought it 3 years ago for a workshop yet never got the workshop going so... it is new but out of warranty. Humm...
Rang around forthe same model and each shop I rang had a cheaper price. Started at 2800 after 4 suppliers I was down to 2,400 and that is over the phone. So I recon the Lincoln out of warranty should be worth $1500 not more.
Then someone suggested a Liquid Arc 250, allegedly made by Lincon in Australia and painted blue in stead of red...well that is what they told me... The duty cycle is the same anyway, the price is (after a few more calls) 1600 plus GST. Well 250 amps is probably as much as I will ever need I recon. The last sticky point is the nuisance of the bottle and its rental not to mention content. One guy told me he provides 4.9 m3 in his E cylinder and that is why he charges $90 per cylinder content whilst the others only have 3.5 m3 and charge less, $55 and up. I think I must sound like a classic sucker on the phone hehe.:roll: Don't the cylinder get filled up by BOC or something similar?

Anyway my little try on a gate I need for the side of the house brought me back memories of metal fabrication and wrought iron. the smell of the melting rod, swinging the electrode lead over the shoulder to avoid the annoying tug of the cable, holding my breath whilst welding...I have always done that don't know why, do the same before shooting.
Thank you all for your input, I suppose I have yet to decide which way to go. It will probably come down more to opportunity then to planned decision, who knows I may find a rotary in need for a good home
I may sign up to one of those evening welding courses just to have a bit of a yarn about things.
Hooroo

Gumnut
15th Jul 2007, 11:10 PM
Hullo Marc. I haven't fully read all the postings and so am jumping in a bit with my two bobs worth. I have pressure tickets for both tig and mig welding. Tig is slower but gives control and finnish, think bicycle frames. Mig deposits the weld faster, think constryction. Mig to the novice or cowboy appears to be quite easy, just pull the trigger and point the gun..........................

When I was looking at buying my first mig, my elder brother gave me the excellent advice, 'buy the biggest single phase machine you can find'. That means about 250 amps, the brand doesn't matter to much. That first machine of mine has paid for it self a hundred times over by now.

Last year I brought a Kempi 180 (180 amps) Mig Inverter. They are light as, take gas or gasless wire, can throw them over your shoulder and weld from a ladder, they bight into the steel, can deposit a good 6mm weld leg length on max settings and retail for about $2300. They have such a good rap that I formed a pod of three buyers, we ordered three machines and got the price down to $1650 ea. The only weak point I have found is the light weight gun got so hot on my first job that the gas line melted and slipped off the gun. Kempi replaced it with a heavier one, definitely a design fault. This is the most beautifull of machines and the digital interface makes it easier for the novice to understand the settings and paremeters.

And if you really want to hone your skills I suggest giving TAFE a Captain Cook. The welding courses are cheap and modular so you can pick up units as it suits.

Is there a forum like this for steel eyes?

Gumnut.