# Tykes of welding - help please



## Mark-numbers (30 Nov 2014)

Hi guys 

I am after a little bit of help please.

I am just setting up a metalwork shop as an additional entity to commercial joinery shop I have. We want to bring the metalwork we sub out in house. 

Can someone explain the differences in mig and tig welding in layman terms please? 

We will be welding mainly mild steel and in only small sections - 20mm tube to 40mm flat plate, and we occasionally have to supply brass! 

Thanks in advance


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## bourbon (30 Nov 2014)

mig welding will be fine for that. For brass you will need brazing kit


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## Mark-numbers (30 Nov 2014)

Thank you - what is tig welding? Is that for more structural stuff?


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## jimmy_s (30 Nov 2014)

Tig welding uses a tungsten type electrode, you generate the arc between the tungsten and the workpiece and use a separate filler rod in a similar way to how you would gas welding. You use a shielding gas as you would normally for Mig welding. The tungsten rod does not burn away (at least not if you are doing it correctly lol).

I wouldn't say its for structural stuff. Its quite versatile - you can weld many materials with it (if you have the right setup) you have a lot of control over the process as you feed the filler rod in manually and can control how the arc behaves.

It does however take a bit of getting the hang of I would say.


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## Mark-numbers (30 Nov 2014)

Thank you.

Why would some people use TIG and some use MIG?

There has to be reasons? is it strength - cost - finish?

Is a mig weld stronger than tig or vice versa?

Apologies in advance


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## CHJ (30 Nov 2014)

We used TIG welding extensively on Aircraft and ground Gas Turbine parts such as Exhaust systems and after burner plates and other structure parts using Titanium and exotic alloys. Using Argon as the inert gas to flood the weld area (via a 1" pipeline to welding stations to give sufficient flow rates). 

Welders were trained and certified, costly and time consuming, to get to the required standard, regular checks had to be carried out on sample welds, cross sectioning, polishing and microscopic inspection of weld for porosity and any slag inclusions.

Think anyone specifying TIG welding would be expecting some form of Quality Assurance and be prepared to pay for the skill level of the operator.


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## Mark-numbers (30 Nov 2014)

ahhh ok - So a mig welder will be the perfect solution on a small scale?

I need to have some degree of what I am talking about when ordering kit to make sure I don't overspend or even underspend.

Is there anything i need to look for when buying a mig welder?

The idea is to get the metalwork area set up then get a metal worker employed. chicken and egg situation.


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## doctor Bob (30 Nov 2014)

If you got the metal worker first couldn't you then use his/ her knowledge to ensure you buy correctly.
You can still set up the area, I would have thought the equipment could be ordered and delivered within 2 days.


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## Mark-numbers (30 Nov 2014)

I would prefer to get the area set up first, as I have a pal who can use it, but he can't help me in making the decisions on buying the kit unsure why, but he is a numpty!!


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## CHJ (30 Nov 2014)

doctor Bob":1gwxjqlg said:


> If you got the metal worker first couldn't you then use his/ her knowledge to ensure you buy correctly.
> You can still set up the area, I would have thought the equipment could be ordered and delivered within 2 days.



Likewise I would think a suitably qualified welder with a good CV would be the better option to specify equipment than someone who does not have a working knowledge of welding. 
Bit of chicken and egg though, we would have had a welder do some test welds on known certified equipment as a means of proving his standard.


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## jimmy_s (30 Nov 2014)

If you are welding mild steel mainly a Mig should be fine. I would doubt you will weld brass but if the need arose you would need to use Tig. I doubt many people would weld brass in any case - you would normally silver solder or soft solder it.

What would you be fabricating btw?


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## Mark-numbers (30 Nov 2014)

We manufacture furniture for restaurants and some of this furniture has rustic metal incorporated into them, like fiddle rails etc etc, all very very basic stuff. 

I will have a look for some photos of what we have had made and post them up.


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## spinks (2 Dec 2014)

With MIG, for what you need it for I would go for something small, about 160 amps or so....anything bigger is just a waste of time for small stuff like what you need. I would go for a gas mig rather than gasless (gasless uses a flux core wire and leaves a "slag")....If you go to your local BOC depot they will advise you well (you can always get their advice and buy the plant they recommend online) and use a shielding gas (argoshield 5% for your stuff) try and get something that will use a full size roll of 1mm wire as that is a cheaper way in the long run. try and avoid budget makes such as "sealey" as they use nylon rollers rather than steel and dont have the best customer service!! I would go for a decent mid range plant from boc and try and negotiate a decent price on the bottle rental!!


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## dickm (2 Dec 2014)

spinks":2b8qy3rl said:


> try and negotiate a decent price on the bottle rental!!


Let us know if you succeed. From experience, BOC make the average payday loan shark look like a pussycat.


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## woodpig (2 Dec 2014)

There seem to be two reoccurring themes when it comes to MIG welders for DIY'ers. Poor wire feed and cost of Sheilding Gas! Sort those two and you should be fine!


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## Mark-numbers (2 Dec 2014)

Looks like I have settled on A miller migmatic 220 which is slightly more than I wanted to spend!!


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## Stu_2 (3 Dec 2014)

I can recommend Weldequip as a supplier. They do some decent machines at keen prices, and their customer service is good. 

I use Hobby Gas as a supplier. Rates are good for small volume users. No bottle contracts required. 

Cheers
Stu


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## spinks (3 Dec 2014)

Mark-numbers":vxkt799l said:


> Looks like I have settled on A miller migmatic 220 which is slightly more than I wanted to spend!!



Miller is a good make, reliable, good customer service and easy to set up and use....IIRC BOC are doing a special on bottle rental...1/2 size bottle £10 a year or so and refils about 30 quid ish....avoid the advice to use co2 "pub gas" as it lease a dirty weld with hidden porosity inside it!!


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## Mark-numbers (3 Dec 2014)

Luckily for me BOC are on the same estate as us!

Thanks for all your help gentlemen it is much appreciated


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## Myfordman (4 Dec 2014)

If you can't keep the MIG welder in a dry environment, then take the wire out and keep it in the house other wise it will rust and jam


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## Mark-numbers (4 Dec 2014)

Thank you for that tip, although it will have to stay in the factory unfortunately - is it worth just recoiling the wire in not going to be in use for a few days?


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## n0legs (4 Dec 2014)

Mark-numbers":q4018i4c said:


> Thank you for that tip, although it will have to stay in the factory unfortunately - is it worth just recoiling the wire in not going to be in use for a few days?




Try one of these in the wire cabinet, they seem to work fine inside mine. Cheap as chips, change them every couple of months (or when I remember)  
https://www.google.co.uk/search?q=damp+ ... nxYt8AM%3D


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## Eric The Viking (5 Dec 2014)

Avoid "pub" gas, for all sorts of reasons, including poor welds - leave it to farmers welding gates, etc! 

Argoshield is wonderful (get a decent regulator that lets you see pressure and flow rates). You can do stainless with MIG + pure argon shielding, but it's not easy (the chromium migrates out of the weld if you're not careful, leaving a weld that _isn't_ stainless!).

If at all possible, keep the wire warm and dry (yup, I bring mine into the house, too). A cupboard with a small greenhouse-style heater (one of these) ought to be enough*. As long as the air is slightly drier than the surroundings, it shouldn't corrode.

Don't neglect the mains supply. I have a small semi-industrial SIP (not quite DIY, but not quite pro either). The weld quality improved enormously when I fitted it with a 16A plug. Welders take high surge currents when the arc is struck, and if there's a significant drop in voltage at that point, it makes life frustrating as the welds can look (and be) poor quality. Voltage drop comes mainly from thin cable between the welder and the incoming mains supply, both its lead (flex) AND the permanent wiring in the premises. I doubt Miller kit will come with a cheap flex, but don't skimp on the supply you're putting in, for that reason.

Many people would give an arm for Miller kit - but then again it would be that much harder to weld afterwards!

E.

* I tried wiring two of these in series, to halve the power consumption (I have one under my tool storage as my garage/workshop gets very damp in the autumn). It didn't work as there simply wasn't enough heat, but if you're only storing wire in a smaller space, it might.


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## woodfarmer (5 Dec 2014)

I think it would help you make the right decision if you went to evening class or to a skilled person with a sample of what you want to weld and had a go at both. To me mig is good for some structural stuff slightly rough. Stick welding the same but even rougher. Tig gives better finish and can work very well with very thin sections once you have the skill.

IE welding stainless steel
You will always see the ripples using stick or mig
tig can look as if the item had been cast as one piece. (good enough for jewelry).


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## wizard (5 Dec 2014)

negotiate with BOC your having a laugh. I get charged a handling charge and have to lift the bottle on my own.


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## Mark-numbers (5 Dec 2014)

The good advice keeps coming, much appreciated.

I went to place an order for the miller, but isn't available from my supplier until the new year - in my eagerness I went to machine mart cough cough and bought everything from there - so I have gone down in quality and power. I bought a very simple 165amp Clarke mig welder (cough cough again) 

It seems to do the trick - luckily for us the client loves it the rougher the better! 

I have bought a load of metal and a metal chopsaw so will be getting my hands dirty next weekend and getting familiar with it all!


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## Boatfixer (9 Dec 2014)

Nowt wrong with the little Clark welders - the prototype and probably first 10 of the veterinary operating tables I build were made with a Clarke 150 amp mig and disposable gas cartridges....





With a machine that uses relatively little gas like yours look for "Hobbyweld" gas bottles. Full size bottles like I have to use on my current 3 phase 400 amp Hobart welder are overkill for you and tend in my experience to end up costing far more than the price quoted.....

Keep your metalworking area completely separate from any woodworking you do. I cannot in my workshop and it is a right pain covering everything up to keep grinding dust off woodworking machines and customers boats....


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## dickm (9 Dec 2014)

Boatfixer":3aefgx14 said:


> Keep your metalworking area completely separate from any woodworking you do. I cannot in my workshop and it is a right pain covering everything up to keep grinding dust off woodworking machines and customers boats....



.......... to say nothing of the fire hazard.


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## colinc (12 Dec 2014)

Hi,

I am about to do something I never would have expected a while back and suggest people look again at BOC. 

For years I had an Argoshield (argon co2 mix for MIG) bottle on rental and after not using it for a year took it back to stop paying the exorbitant charges. I am now at a point where I am thinking of getting a CAA approval to do welding on my aircraft project. I have bought a decent TIG welder and had been shopping around for pure Argon. 

I tried BOC, Hobbyweld and also Air Liquide's Albi options and decided that the latter best suited my needs. BOC were the most expensive, Hobbyweld reasonable but small bottles and AL's big cylinder at about £200 one time charge and £40 refill seemed good as you got more gas for the same money as Hobbyweld.

However, just before buying that I got a call from a very helpful lady at BOC who explained that they'd like to be more competitive for small users and we agreed what I think is a good deal on the Y size cylinders (the short but fat one). I pay £4.50/month rental which is about half their previous rate for my old smaller cylinder, and £12.00 for a refill. Also they dropped the much hated handling charge. The prices are capped with only a small increase over three years.

I think that for someone using a number of fills per year it's a good deal.

So, do give BOC a try as they seem to have responded to the competition at last.

Regards,

Colin


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## Tinbasher (20 Dec 2014)

The best advice is really to find your welder first. Get the wrong gear and you might find your paying too much on consumables or getting a less than satisfactory finish.

I wonder what your view would be on a skilled blacksmith setting up a woodwork shop with no experience?


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## Mark-numbers (21 Dec 2014)

Thanks for all the advice - the area is pretty much set up now and have already done our first jobs, which the clients loves. 

We are lucky that space is available as it is (7000sq ft) and can keep the welding area completely separate.

If a skilled blacksmith set up a joinery shop, then fair play to him, however I have set it up because the bits and pieces I have made out, are very very simple, and cost more in fuel and wages to fetch them than it costs me. Its there for convenience rather than a money making exercise.


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