Tykes of welding - help please

[Mark-numbers]

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

 

[bourbon]

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

 

[Mark-numbers]

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

 

[jimmy_s]

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.

 

[Mark-numbers]

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

 

[CHJ]

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.

 

[Mark-numbers]

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.

 

[doctor Bob]

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.

 

[Mark-numbers]

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!!

 

[CHJ]

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.

 

[jimmy_s]

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?

 

[Mark-numbers]

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.

 

[spinks]

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!!

 

[dickm]

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.

 

[woodpig]

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!

 

[Mark-numbers]

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

 

[Stu_2]

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

 

[spinks]

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!!

 

[Mark-numbers]

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

Thanks for all your help gentlemen it is much appreciated

 

[Myfordman]

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