[rally4x4racer]

so i just have to use aluminum wire? also you must sheild the weld with gas when welding aluminum? or its just preffered?

did you mean to post a link or were your making a refrence?

thanks

[julmer]

Absoutely have to use shielding gas with aluminum. There is no such thing as flux cored aluminum wire.
It sounds funny but the best way to describe the requirements for welding aluminum are sterile.

[fourbyfourblazer]

Some things to remember when welding aluminum.

Make sure the aluminum is clean of all grease, dirt, etc., by using a degreaser/solvent. Before you weld you must remove the oxide on the surface using a stainless steel brush that cannot be used for other metals otherwise it contaminates the welds or us an oxide cleaner.

If you store aluminum in cold places you should bring it up to room temperature, eliminating condensation. Do not heat cold metal with an oxyacetylene torch (which is a common practice, but not a good idea). This can introduce carbon into the oxide coating.

At the end of the weld you should keep the gas on the weld bead for about 15 - 20 seconds to prevent cracking.

[rally4x4racer]

thats pretty helpfull information, thanks 4X

its the same sheilding gas for aluminum as for steel ect right?

[AlanTA]

I also have never welded before, but just got a '78 formula that I need to put a quarter on. (hince an excuse to buy more tools I've been reading some and am thinking about a Miller 135. Would that work for frame work as well as sheet metal? I doubt I would do anything that heavy, but just incase I get ambitious.

[julmer]

I think pure argon is required for MIG welding aluminum. I know that's what I have to use to TIG it.

The Millermatic 135 is one of the better 120 volt welders. It would do light frame work but you might need to do multi-pass welding occasionally. The 240 volt 175 is a better choice if you have the wiring to support it. It will have a heavier single-pass capacity and the larger welders are usually very smooth a low currents.

So, if you need a 120 volt unit, the Miller is a good choice.

[rally4x4racer]

100% argon for welding aluminum, and 75% argon 25% CO2 for solid wire. - at least thats what it says on the inside of the welder.

whats the biggest wire the hobart 140 will take?

also whats the deal with the gas? it shows in the manual that it plugs into the back of the welder. does the gas travel trhu the handle ?? like i just plug in the gas and turn on the regulator valve.?

weird - i pictured it as gas in one hand - welder in the other lol.

someone clue me in please.

thanks r4r

[Beenaway2long]

Having bought a Lincoln 175 Tig and a 125SP Mig(6 years old,now), I have not had a problem with either. To do it over, I would stick with the 175, but go alittle heavier on the mig. The manual says it will to 5/16". As easy as mig is, I wish I could do 1/2" single pass. I still stick weld anything 1/4" or better. I just trust the penetration more than the mig.

Think about your purchase before buying.

1.) Buy a P.O.S., and what do you have? P.O.S.
even if you don't use it, you will get ZERO resale.
If you keep it, you will always want to upgrade it.

2.) Buy the best you can buy, and if you ever decide to bail, you can resell in a heartbeat. You will RARELY ever upgrade the best you can buy. You only have to buy it once. Money saved in the long run!

[rally4x4racer]

whats the deal with stick welding?
its just actelyne and O2?
braising the same thing ?

[fourbyfourblazer]

[rally4x4racer]

do i need a degree to understand that?

ill be back to look at that later, like years later when im old enough to understand it.


ha ha thanks 4x4.

so braising is braising, gas is gas and can be shielded, and mig is metal electrode arc welding.

can we get a scientist in here?

[julmer]

Three basic kinds of arc welding:
1. Stick welding
2. MIG welding
3. TIG welding
Stick uses a coated electrode clamped in the jaws of a holder.
MIG uses a small wire fed through the torch handle and shielding gas flows around it. A subset called flux core uses the same machine but no gas. The wire has flux material in the center of it that melts/burns and provides the shielding
TIG uses a torch with a tungsten electrode to make the heat and filler is added manually. Similar gas shielding to MIG

There is also oxy-acetyline or gas welding where the two gasses are mixed and burned at the tip of a torch to make the heat and filler is added manually.

MIG is the easiest and fastest.

[fourbyfourblazer]

Stick Welding

Shielded Metal Arc Welding (SMAW) is frequently referred to as stick or covered electrode welding. Stick welding is among the most widely used welding processes. The flux covering the electrode melts during welding. This forms the gas and slag to shield the arc and molten weld pool. The slag must be chipped off the weld bead after welding. The flux also provides a method of adding scavengers, deoxidizers, and alloying elements to the weld metal.

Stick Welding Benefits
Equipment used is simple, inexpensive, and portable
Electrode provides and regulates its own flux
Lower sensitivity to wind and drafts than gas shielded welding processes. All position capability.

Common Stick Welding Concerns:

Arc Blow
Arc Stability
Excessive spatter
Incorrect weld profile
Rough surface
Porosity

-------
MIG Welding

Metal inert gas welding: a method of welding in which the filler metal wire supplies the electric current to maintain the arc, which is shielded from the access of air by an inert gas, usually argon.

Gas Metal Arc Welding (GMAW) is frequently referred to as MIG welding. MIG welding is a commonly used high deposition rate welding process. Wire is continuously fed from a spool. MIG welding is therefore referred to as a semiautomatic welding process.

MIG Welding Benefits

All position capability
Higher deposition rates than SMAW
Less operator skill required
Long welds can be made without starts and stops
Minimal post weld cleaning is required

MIG Welding Shielding Gas
The shielding gas, forms the arc plasma, stabilizes the arc on the metal being welded, shields the arc and molten weld pool, and allows smooth transfer of metal from the weld wire to the molten weld pool. There are three primary metal transfer modes:

Argon
Spray transfer
Globular transfer
Short circuiting transfer

The primary shielding gasses used are:

Argon
Argon - 1 to 5% Oxygen
Argon - 3 to 25% CO2
Argon/Helium
CO2 is also used in its pure form in some MIG welding processes. However, in some applications the presence of CO2 in the shielding gas may adversely affect the mechanical properties of the weld.

MIG Welding Problems

Heavily oxidized weld deposit
Irregular wire feed
Burnback
Porosity
Unstable arc
Difficult arc starting

Flux Cored Welding


Flux Cored Welding
Flux Cored Arc Welding (FCAW) is frequently referred to as flux cored welding. Flux cored welding is a commonly used high deposition rate welding process that adds the benefits of flux to the welding simplicity of MIG welding. As in MIG welding wire is continuously fed from a spool. Flux cored welding is therefore referred to as a semiautomatic welding process. Self shielding flux cored arc welding wires are available or gas shielded welding wires may be used. Flux cored welding is generally more forgiving than MIG welding. Less precleaning may be necessary than MIG welding. However, the condition of the base metal can affect weld quality. Excessive contamination must be eliminated. Flux cored welding produces a flux that must be removed. Flux cored welding has good weld appearance (smooth, uniform welds having good contour).

Flux Cored Welding Benefits

All position capability
Good quality weld metal deposit
Higher deposition rates than SMAW
Low operator skill required
Metallurgical benefits that can be gained from a flux

Flux Cored Welding Concerns

Melted contact tip
Irregular wire feed
Burnback
Porosity

-----
TIG Welding

Tungsten-electrode inert gas welding: a method of welding in which the arc is maintained by a tungsten electrode and shielded from the access of air by an inert gas

Gas Tungsten Arc Welding (GTAW) is frequently referred to as TIG welding. TIG welding is a commonly used high quality welding process. TIG welding has become a popular choice of welding processes when high quality, precision welding is required. In TIG welding an arc is formed between a nonconsumable tungsten electrode and the metal being welded. Gas is fed through the torch to shield the electrode and molten weld pool. If filler wire is used, it is added to the weld pool separately.

TIG Welding Benefits

Superior quality welds
Welds can be made with or without filler metal
Precise control of welding variables (heat)
Free of spatter
Low distortion

Shielding Gases

Argon
Argon + Hydrogen
Argon/Helium

Helium is generally added to increase heat input (increase welding speed or weld penetration). Hydrogen will result in cleaner looking welds and also increase heat input, however, Hydrogen may promote porosity or hydrogen cracking.

TIG Welding Limitations

Requires greater welder dexterity than MIG or stick welding
Lower deposition rates
More costly for welding thick sections

-----
Soldering and Brazing

Soldering and Brazing are joining processes where parts are joined without melting the base metals. Soldering filler metals melt below 840 °F. Brazing filler metals melt above 840 °F. Soldering is commonly used for electrical connection or mechanical joints, but brazing is only used for mechanical joints due to the high temperatures involved.

Soldering and Brazing Benefits

Economical for complex assemblies
Joints require little or no finishing
Excellent for joining dissimilar metals
Little distortion, low residual stresses
Metallurgical bond is formed
Sound electrical component connections


Soldering and Brazing Issues
We can help optimize your joining process variables. Evaluate your current joining parameters and techniques. Help eliminate common joining problems and discontinuities such as those listed below:

Soldering and Brazing Joining Problems

No wetting
Excessive wetting
Flux entrapment
Lack of fill (voids, porosity)
Unsatisfactory surface appearance
Base metal erosion

[rally4x4racer]

well anyone care to know how my first welding experiment went?
ha ha ...

so i take it stick welding is not a bad idea... or braising and you can weld bigger stuff
generally bigger than this 140 will do.

oxy-acetylene sounds fun. thats the oldschool way looks like.

any dierect comarison - which welds better or heavier guage - or costs less?

4x4 did that post come directly off your hard drive of resources

nice job - now im going to have rate this thread A+
great ebayer

r4r
ps- is the orange stuff on the steel after welding oxidization? how do you combat it?

[fourbyfourblazer]

After welding for 10 years i've accumulated alot of resources. I took stick welding in high school and then when I was around 25 I worked for a motion picture company where I was taught how to TIG weld. Took a combination welding class at an occupational center to brush up on any thing I didn't learn on the job. Eventually I worked for a biotechnology company and got my welding certification for pressure vessels and i also have an orbital welding certificate from Arc Machines Inc.

Custom car builders still use oxy-acetyline. I've watched Gene Winfield section a bumper a few years ago and weld it back using this method. Tig welding could do the same thing but it cost more for the equipment. No need to fine tune a tig setup like the oxy-acetyline.

How heavy is the gauge you want to weld? Are you welding I beams? I would recommend stick for that. Mig is good for large and small gauge materials. Tig is best for thinner materials 3/16" and less. I actually welded a stainless steel tank that was 3/8" thick but I had to make multiple passes and use lots of heat. My boss was a ding dong for not buying a MIG set up but since he had already shelled out $35 grand for an automated TIG machine I had to use what we had.

The mig welding machine is the best bang for the buck. I worked for a generator manufactuer that had started out building c-channel frames with a basic 110v mig welder and eventually bought a 220v MIG setup when they started selling the generators.

The type of brazing i'm most familar with is Furnace brazing. I would tig weld the outside of the heat exchangers and then the company would send them out and have the tubes on the other side brazed by another company.