Let's discuss these items
Electrode choice - Most of these small machines will come with flux cored wire. (The shielding flux is inside the wire and requires no shielding gas) Flux cored wires and small limited Amperage input/output hobby welders are not a match made in heaven.
There is more than one kind of flux cored wire 1) flux cored without gas 2) flux cored with gas.
Flux cored wire does have it's place. It is a high penetrating process that will not go away. But most hobby welders lack the know how to run it and don't care for it's weld appearance. In addition, most small wire welders don't have the duty cycle to run flux cored wires for any length of time.
If you choose to run it we suggest the following -
1) Increase your stickout (distance between the contact tip and base metal to 1/2" as this allows the core flux to melt and become gas and liquid in the molten puddle.
2) Increase your voltage as most flux cored wires prefer a longer arc length and in wire welding voltage=arc length.
When wire welding always remember -
Voltage = Arc length (you can also think of it as weld width) Why? The higher the voltage, the longer the arc length, and, the longer the arc length the wider the weld.
3) Use inline motions. Inline motions (drag, 1/8" forward stop repeat ) allow the molten puddle to maintain heat and eliminate the chances of welding over flux already deposited.
We have small welders set up side by side for users to compare. 1) flux cored without gas 2) flux cored with gas 3) solid core (Er70s6) with 75/25 gas
When users try #3 they don't want to go back to #1 or #2.
SO if you purchase one of these machines keep in mind that you might want to opt for the gas kit so you can make the switch and remember you'll probably have to. HOWEVER, don't toss the flux cored wire in the trash can ! You might have some applications (i.e... outside in windy conditions, in the field where gas is not portable enough) to use it.
Gosh that took a long time ! The next ones are easier !
Gas Choice -
CO2 - Carbon Dioxide is the least expensive, most penetrating of the 3 with the least weld flow and poorest weld appearance.
75/25 - Argon/CO2 is more expensive, less penetrating than CO2 but have good weld flow and weld appearance. This is the most commonly used.
92/8 - Argon/CO2 is the most expensive and least penetrationg of the three and provides excellent weld flow and appearance. It is excellent for thin metals and auto body work.
Duty Cycle - The amount of time in 10 minutes a machine can perform (weld) at a given amperage. Example - 50% at 60 amps means you can weld 5 minutes out of 10 minutes at 60 amps.
Input Amperage - The required amperage delivered to a machine. This is a point that many people forget when purchasing a machine. If you purchase a 110 volt machine and plug it in to an outlet in your garage which has other items pulling from it you will have input amperage issues. It's a good idea to have a dedicated circuit for your welder or you will be tripping the breaker every time you weld.
Total output amperage - The Amps the power source will deliver for a given duty-cycle period. You just can't expect a 110 volt machine to deliver more amps than it's capable of.
Don't get us wrong ! Small wire feed welders have a place in the world but you have to realize that they have the highest return rate of any welder on the market.
Hopefully now you know why, and know if one belongs in your treasure chest of equipment in your shop.
Just our 2 cents
Good Luck !
Staff- weldguru.com