Topic: MIG or TIG?

[joe29]

I've always wanted to learn basic welding and found a local shop offering a series of introductory classes.  They offer classes for MIG and TIG.  Which should I take?  I see myself welding frame hoops (BCR style) and simple mounting brackets for rearsets, gauges, etc.  That's probably the most welding I would want/need to do.  

Any thoughts?

Here are the class descriptions:
http://techshop.ws/take_classes.html?categoryId=Welding+%2F+HotShop&submit=Change+Category

[scottly]

If you are only going to be welding steel, I would go with MIG. These are point-and-shoot welders, are easy to use, and small ones are reasonably priced. TIG welding is more versatile and more precise, but takes greater skill to master.

[tramp]

mig is for general welding
tig is for fine welding
as a rule of thumb

[syth82]

If you learn tig, mig is easy. If it's one or the other,  I'd go for the tig class.

[sangyo soichiro]

I'd search vids on youtube if I were you.  It might help you decide.

[Alan F.]

If you learn tig, mig is easy. If it's one or the other,  I'd go for the tig class.

+1

[Terry in Australia]

If you learn tig, mig is easy. If it's one or the other,  I'd go for the tig class.

+1

+ Another one. I bought a MIG years ago, and after a couple of hours I was welding like a pro. I've owned an AC/DC TIG since March and I'm still struggling. Nothing wrong with knowing too much!

[joe29]

Thanks for the feedback. I went ahead and signed up for the MIG class. I think MIG will cover the basic stuff I want to do and sounds easier to get the hang of.

[scottly]

When you go to buy a welder, I would recommend a 220 volt input unit. The 110 volt jobs are a bit gutless, especially when used with gas, vs flux-core. My personal preferred brand is Lincoln..

[Terry in Australia]

Yep, I've got a 220 AMP, 240V MIG and it'll weld anything from tin cans to railroad tracks. Don't buy a "gasless" MIG, they're shiit.

[scottly]

Flux-core has it's place. Greater penetration than solid wire with gas; that's why the cheapie 110 volt jobs tend to be gasless. My 135 amp, 220 volt Lincoln has served me well for 18 years now, both with flux-core and solid wire/gas...

[KeithTurk]

I've got a SP135 Lincoln as well as a Lincoln square wave Tig....  I'd go Mig first as well... thought I'd take the Class in Tig cause it's going to be a much steeper learning curve....

I've had both 220 and 110 Mig's and far prefer the 110 simply because with a fair extension cord I can go anywhere...

K

[scottly]

You should have heard my buddy #$%*ing about his 110v Miller this afternoon; he was ready to pitch it down a mine shaft!!!
My Lincoln is also an SP135. I saw recently Lincoln has a very reasonably priced spool gun, for welding aluminum, that will work on our machines.

[KeithTurk]

Lincoln also has a push set up for a Mig gun..simply change the liner to a .045 liner and push .030 Aluminum wire through it with Argon...

Downside is, like the spool gun... it takes a bunch of practice and set up time...  but once your doing it every day it's pretty good...

The Tig is the poo poo for Aluminum work... it's just very controllable...

K

[ZanderJay]

If we are going to choose what the best welder was, we might to think about the feature and the purposes why we need it. You can determine the function of the welder. For me, I having use the MIG welder and I assume that this welder, I can used every single day I weld.

[Boner]

Maybe Zander can clear something up for me with his course instructor, when I took my apprenticeship cough cough a few years ago mig was quite new.
At that time my welding instuctor told me Mig with or without gas was a very porous weld and therefore very weak and not to be used for sturctural welds. Stick is a farmers weld but is much stronger and Tig is the cats ass.
Thanks
Bones

[Don R]

tig is for building the bike
mig is for building the trailer

[scottly]

What welding process did Honda use to weld the CB frames?? My guess is MIG.

[Don R]

From the appearance I'd say mig

[memet14]

MIG and TIG are both shielded arc welding applications, they are very different from one another. MIG welds are created with a consumable electrode, while TIG welds are created with a non-consumable electrode. TIG welding typically includes filler metal as well. That's what I got in my research. I've been using TIG in my welding activities. This is the best weld for me.

[jgmmgood]

Personally, I wouldnt trust MIG on anything that needs to be dependable, IE:  frame joints, etc.  Stick welding (also known as SMAW or shielded metal arc welding) is very sound if the processes are understood and care is taken in preparation. 
TIG welding is extremely strong as well - again, if the process is understood.
Welding is a bit like painting in the fact that proper preparation is a key point.  Also key is knowing what makes a weld "bad" and trying to account for it. 
For example, on any type of weld, porosity is the enemy as well as contamination.
Porosity can be caused by may factors such as moisture, incorrect gas flow, wrong voltage/amperage, wrong angle of electrode, etc. 
Contaminiation can also be very detrimental and can be caused from "contaminants" such as ill-prepared surfaces, dirty filler material, dirty electrode (TIG), etc.  Grinding starts and stops is also a key to ensuring a good weld. 
Bottom line is that good welding takes practice and understanding what is happening will help ensure a dependable weld. 
At least that is what I was taught in the nuclear plant welding school back in the Navy days. 

[754]

Learn to jog before you run... I doubt they would even bother to sign you up for TIG class if you have no prior experience..


 ..hey..what the heck happened to Heli-arc......?... JK..

[70CB750]

There is nothing wrong with Mig for structural welding - if you know how. I saw Mig welded valves for nuclear power stations and the following X ray only confirmed the quality of the weld - and the safety koeficient for that job was much higher than motorcycle frame.

But home owner who just got a HF buzz box should not attempt to weld anything important:)

[Don R]

Heli-arc is tig, they just stopped using helium for a shielding gas. Hence the name change.

[Terry in Australia]

I wouldn't be fussed about MIG welding for motorcycle frames, Ducati MIG welded their beautiful steel "Trellis" frames for 30-odd years and I haven't heard of one disassembling itself yet? Cheers, Terry.

[rbmgf7]

I started on TIG before MIG. I had a guy teach me who TIG'ed for a few years. It's really not hard to lay a bead but it is hard to get good penetration and lay a good bead without excessive heat to your part.

My explination is going to be based on a professional welder (no, I'm not professional but it's what I was taught):

TIG has a lower heat affected zone (HAZ). It's the area surrounding your weld which changes composition from the heat. MIG tends to have a wider HAZ. In essence, HAZ isn't good since the rapid heating and cooling weakens the part just outside the weld. Usually what you'll want to do is anneal your part to relax it and restore it to it's near original state.

Most will debate TIG or MIG has better penetration. It's really dependent on the welders ability. If he knows how to weld, he could get great penetration and maintian a low HAZ with a MIG.

MIG is used in large scale manufaturing all the time since it's efficient. The automated machines are calibrated to give a good weld.

TIG is great because of it's adjustability. You have the ability to change electrode diameters for narrow or wide welds, pre and post flow, foot control, short wand extension for tight spaces, etc. Most TIGs are also AC which is needed for welding aluminum. TIG welding aluminum is a completely different ball game! Albeit, the price for a baseline TIG can get you a really good 220 MIG.

For sheet metal and thin walled tubing, I'd go with a TIG. For framework, exhaust welding, etc. a MIG will do fine.

[Kong]

Well, if you've ever done brazing with a gas torch and a brass rod you'll find TIG pretty easy, it is from the welder's point of view a very similar process.  I can't imagine anyone just starting with TiG; MIG is like baby steps on the way to learning TIG is the way I've always thought of it.

By the way, Lincoln in a wholly owned subsidiary of Miller. 

[rbmgf7]

I though Miller owned Hobart?

[Raef]

What welding process did Honda use to weld the CB frames?? My guess is MIG.

mine looks as if some of it could had been done with a torch, I can find no evidence it was done with a mig welder, especially the back bone and the sheet metal stamped gussets.

Mig is somewhat similar to stick welding in the respect that the heat is added using the filler metal as a conductor so sometime it is hard to get a good heat to filler ratio especially with inconsistent joints. This is why you sometime get the weld that don't stick, to much metal filler and not enough heat, dirty surface, or loss of shielding gas. We have 3 wire welders the biggest 220 unit is probably 30 years old, of the 2 smaller ones one is dual voltage and 1 is 110. I use the 110 unit the most and it works very well up to 1/4"

Tig welding and  Oxy acetylene torch welding are similar in the respect that you add heat then filler metal using the heat to draw the filler to the desired location. Tig is much easier than a torch but they both have a place. We use a torch for nearly all of our sheet metal work, I have recently started building aluminum stuff and I have been using a gas torch for that also

Mark