mig or tig what do you use more in your shop and why?

[Jason Perkins]

I'm getting ready to get my own welder, insted of running around and having other people do it for me. I have taken some things to a friend who is a fellow gunsmith, he only uses a tig and loves it and said he can control the heat better with it. I have taken things to a welding shop and thinking they would use the tig on the part, only to see they used the mig. Theres no splater on a tig, I like that! I have a few thousand hours on mig welders, and I can weld good with one. Should I get both a mig and tig or should I just get one? What do you use in your shop and why???

[outerlimits]

Mig is gay...

[JimmyZip]

Mig is good for production welding, where volume is important. Tig is good for precision. If I was welding something like anything on a pistol part, I would go tig. You can get tight welds with that little tip, and your foot control is just really nice as you can adjust the heat as you weld. Harder to learn, but well worth it.

Definitely read up on electrodes too. Just the way you sharpen (or blunt it if you're talking aluminum welding) a tig electrode can really effect torch control. Also, get yourself an auto darkening hood with as large a window as you can find. You will find it makes things easier when you are learning.

JZ

Have too add that mig is better for other things, just cant see you wanting it for gunshithing. If you're weling tables and chairs or large frameworks, I prefer it.

Edited February 24, 2010 by JimmyZip

[DocMcG]

From my experience (former welding teacher) a MIG machine will be more universal and the TIG will provide for more specialty applications. However, as MIG accessories and technology improves, there is little this process can't do!

MIG Considerations:

If you have that many hours on a MIG machine you know full well to run 100% Argon or at least 75% Argon/25% CO2 in order to get the best quality. Spatter can be controlled if the machine is properly adjusted and maintained, however variable voltage control during the welding process is not as accommodating as on a TIG machine. The MIG will be more simplistic to use, but will be limited to mild steels unless you change your set-up, which may take more time than you have. Finally, which you already know, the MIG is easy to operate! The welder who first taught me how to operate a MIG welder told me not to worry because, "a drunk monkey could lay down a pretty bead with a MIG machine!"

TIG Considerations:

If you are going to weld lots of aluminum and stainless in combination with mild steel, the TIG might be the way to go. Of course it creates a superior weld quality in the right hands and can easily move from one material type to another. The process also utilizes Argon as a cover gas and came out of the aircraft industry in the 40's and is popular with specialty applications not unlike gunsmithing. The downside is that there is a rather steep kinesthetic learning curve with trying to operate with both hands and one foot. Also, there is the unforgiving nature of the tungsten electrode. Between resurfacing the electrode and practicing with both hands and one foot on the foot-feed, you will go through quite a bit of material before becoming happy with your performance. With long stringers you will have to restock on filler rather than having a seemingly endless spool of wire as with a MIG. Finally, the TIG is more particular with regard to needing very clean metal to weld, where the MIG chews right through.

The possible answer:

Depending upon how much money you want to spend, both Miller and Lincoln manufacture quality multiprocess machines that excel at both MIG and TIG. Have a look at their websites because they both have nice tools for assisting you in the selection of a machine. Also, if you find the Miller and Lincoln reps in your area they will more than likely get you some time on one of their machines in order that you can make an informed decision.

Good luck!

Kyle

[badmonkey]

I have a good 12 years as a pipe fitter and in that time I have burned a lot of rod mostly stick since then I have moved in to the machinist tried and I do have to say for gunsmithing I truly like TIG got-a love that heat control on the other hand for any kind of prefab of sheet metal or building things like motorcycles and hot rods MiG is mighty nice but for structural steel and pipe stick is the way to go. I learned on an old red lincoln. If I had to pick one make it would be Miller hands down.

[Ray_Z]

One thing that has not been said yet is that if you are going to tig aluminum you need a machine that is capable of AC welding.

[Seth]

I own a Lincoln 215 that I've literally burned about a mile of wire through. But anytime I wanted something done and done perfectly, I took it to the shop and TIG'd it.

GTAW is cleaner, more controllable, has a smaller HAZ, and is definitely the method of choice for material under 1/4" and exotics. Anything over 1/4" and MIG becomes a preferable choice.

I'm going thru my TIG certs right now to freshen up and for smithing work it would DEFINITELY be my first choice.

[mildot1]

I would venture to say that for gunsmith type work 99.9% of the time TIG would be the best choice. You will need to size the shielding gas, tungsten, and nozzle accordingly to the material type and thickness.

If you see any alum in your future you will need AC and a high freq system.For mild steel and stainless you can scratch start but it is not the best method.

Most of the spatter associated with "mig"(this acronym is seldom used, it is GMAW now) can be reduced by using a gas with higher argon content and tuning into the spray mode of transfer. GMAW-P transfer is the best method, runs in spray but not as hot. Cost of equipment may exclude this option.

I have a miller "econo-tig" for my tig and stick work, it is a light duty unit and you cannot pound on it since the torch is air cooled.

I also have a "millermatic 250" set up for mild steel with a spool gun for alum.

I would find a miller dealer and ask to demo some units.

Good Luck

[Ronnie j]

Another aspect is how much time practice time it takes to be as proficient with a TIG as you already are with MIG. The learning curve is steep abnd you will consume alot of argon and tungsten before you are even ok at it.

[Chills1994]

What?

WHAT!

No love for the 7018's???

[larry weeks]

Went to the Lincoln factory school for a week, then bought a factory-reconditioned 275 water cooled for race car work and love it. If you weld more than a few inches at a time the water cooled is the way to go. For small stuff, the air cooled will work fine and they cost a whole lot less. The advances in the last 10 years are amazing, machines are better, cheaper. Am not a gunsmith but have welded quite a few little gun parts for a local gunmsith and you can do some pretty darn fine work with one. They don't "fill" well but you can do some building up if you take it slowly - fixed my overfitting mistakes on 1911 thumb safeties a couple of times. Auto darken helmet with several sensors is important. When you're close to work or reaching around mazes of tubing it's easy to block the sensors.

[jmorris]

No process is ideal for every situation I TIG, MIG and Stick electrode weld often and occasionally Oxy-Act weld.

For gun part work (small things and you want to be very precise with heat control) a TIG is what you’re going to want. You’re not going to do something like this with the other processes.

[Aircooled6racer]

Hello: Buy a good Mig welder first. Learn to use it then get a good Tig machine. I like Lincoln machines. Lastly get a Plasma cutter Thanks, Eric

[jjanglin]

I have both Tig and mig in my shop, I use the Tig for wedling mag tubes,barrel feet,

barrel hoods, cracked slides. Mig can be used for these also. but I prefer the Tig

for most gunsmithing type welding.

Jim/Pa

Sailors

[Jason Perkins]

I see alot of people talking about being able to control the heat on a tig better. I have welded up a lot of parts with a mig and I thought it did great it seemed to be quick and easy, it took a little longer cleaning the part because a little more build-up , but all it took was a second on the trigger and I was done. I always thought by watching a few people tig weld that the parts actualy got a lot hotter and twice the amount of orange area on the part because they have to get the arc going and get it to puddle then feed it filler metal and just because it was a slower process and the part was under the arc longer the part got hotter? Or did they just not do it right? Should they just have ran it for a second and stoped wait a few seconds and start again?

[Seth]

GTAW uses an electrode (tungsten) to create a very concentrated, controlled arc. In terms of heat affected zone (HAZ) tig has the smallest, compared to MIG or Oxy-Fuel. All of the welding forms require that the base metal be at a high enough temperature to fuse the filler with the base material.

What you've observed is either poor penetration with MIG, too much heat with the TIG or just poor technique. The size of a TIG joint can be substantially smaller than the comparable MIG joint, as the heat is concentrated to the tip of the sharpened electrode (steel).

Since the amount of amperage is controlled via foot pedal (or thumb) in TIG, the total amount of heat in the part SHOULD be carefully managed by the weldor. You can tell if its done right by the resulting color.

Edited February 24, 2010 by Seth

[DJM3808]

I like this thread!

MIG for building your pepper poppers and plate racks.

TIG for building your guns.

Stick for your gas / oil pipeline.

[Matt Cheely]

When I go for a good welder, it's going to be a TIG.

[jmorris]

I see alot of people talking about being able to control the heat on a tig better. I have welded up a lot of parts with a mig and I thought it did great it seemed to be quick and easy, it took a little longer cleaning the part because a little more build-up , but all it took was a second on the trigger and I was done. I always thought by watching a few people tig weld that the parts actualy got a lot hotter and twice the amount of orange area on the part because they have to get the arc going and get it to puddle then feed it filler metal and just because it was a slower process and the part was under the arc longer the part got hotter? Or did they just not do it right?

You can control the heat on a TIG much more precise. You are adjusting the current throughout your weld. Look at the photo I posted above, less than .25” from the weld bead (1200 degrees F+) the print on the can is ok, not to mention the thickness of the aluminum at the point of weld is only .010”

Most MIG’s use filler wires in the .035-.045” diameter range and just don’t have the ability to do something like that. They are quick and relatively easy for someone to make a good looking bead. They are just less controllable (like using a fire hose for a water pick). Also, if you are trying to make repairs unnoticeable the MIG will add a lot of work as it does dump a lot of weld down quickly.

[JMcDonough]

I would go with the TIG because you can weld small precise things with the tig and you also have the option to stick weld larger things with the same machine. Miller is the best machines I have used and I have used about every brand out there.

[mike cyrwus]

cosmetically, tig makes a clean, pure weld (usually).

the ability to build up good metal where it will be seen and the ability to apply heat to small localized areas...

-thats why tig.

[Loves2Shoot]

MIG for building your pepper poppers and plate racks.

TIG for building your guns.

Agreed. I don't use the MIG for small precise work, just big quick stuff.

[caz41]

If you know someone with a TIG machine, ask them if you can play with it for an hour. I welded with MIG for years and thought I was a pretty good welder, first day with a TIG and you start all over from scratch.

[jmorris]

I think in order of hard to easy to learn to make a good looking weld they would be (from hard to easy).

Oxy/fuel

TIG

Stick

Mig

One other point many have been focusing on a “good looking” bead. There is a difference in a weld that looks astatically pleasing and one that will pass an X-ray or even dye penetration test. One can make a beauty with a MIG and it not have any penetration into parent material.

[Seth]

I think in order of hard to easy to learn to make a good looking weld they would be (from hard to easy).

Oxy/fuel

TIG

Stick

Mig

One other point many have been focusing on a "good looking" bead. There is a difference in a weld that looks astatically pleasing and one that will pass an X-ray or even dye penetration test. One can make a beauty with a MIG and it not have any penetration into parent material.

Overhead out of position to boot!