Mig Welding Aluminum

[gibbsman]

I have a 115v Lincoln "Weldpack 100" mig welder. I have read that this unit is not capable of welding aluminum due to a lack of amperage, but the users manual says that it can. If the manual is true I need to buy a gas conversion kit, does anyone have any suggestions?

[Weldtutor]

Originally Posted by gibbsman I have a 115v Lincoln "Weldpack 100" mig welder. not capable of welding aluminum due to a lack of amperage, I need to buy a gas conversion kit, does anyone have any suggestions?

Ask a Lincoln sales rep to show you how it welds aluminum.
If the results meet your needs, buy the kit.
You will likely prefer a larger 230V machine, with a spool gun.

[DareBee]

EVEN if LINCOLN tells you to use a gas conversion kit, you will also at minimum need a teflon liner, aluminum won't feed through a steel liner.
IMO you need a 255 and a spool gun (gas of course) as a minimum welder requirement.
I will digress (possibly) - after you spend a bunch of money setting up your machine for aluminum you MAY be able to weld foil

[mxtras]

My advice - don't waste your time or money trying to get a 110 Mig to weld aluminum. You will be severely disappointed at the quality of the weld.

Scott

[diarmaid]

I was asking a welding supplier recently about Mig welding aluminium and I mentioned the spool gun.

He said that most problems with feed in aluminium are because people use the same gun for mild steel, and the steel wire leaves dirt inside the hose, which causes problems for feeding the aluminium wire. Also the aluminium wire expands very rapidly when you strike the arc and the welding tip contracts.

People usually use with .08 wire a 1.0mm or 1.2mm tip which doesn't leave the expanding wire enough room. He said if I use a 1.6mm tip with .08 wire and keep a seperate torch for aluminium that I won't have any problems with feed. So I decided to buy a seperate regular torch instead of a more expensive spool gun when I get my welder. Is he wrong???

Make sure you use a stailess steel brush or solvents and etching solution to remove the aluminium oxides before welding. Dont go too hard with the brush or you might drive the oxides into the material, also if you decide to use solvents and etching solution use a hydrocarbon free degreaser to remove it before welding.

Anyway, re the gas conversion kit...what exactly is this? I thought you just changed your bottles to Argon and purged your machine to weld aluminium.

[Weldtutor]

Originally Posted by diarmaid So I decided to buy a seperate regular torch instead of a more expensive spool gun when I get my welder. #1 Is he wrong??? #2 Anyway, re the gas conversion kit...what exactly is this? I thought you just changed your bottles to Argon and purged your machine to weld aluminium.

#1 Yes, I think he is!
Again, you might ask him to demonstrate for you.
You will probably learn all about aluminum wire "bird's nest" removal from the wire drive system using his method.
The small diameter & very soft aluminum is very difficult to "push" satisfactorily with normal wire drive systems.
Pull type MIG guns with drive rolls in the gun itself, or spool guns are the common solution to the above mentioned problem.



#2 The machine mentioned in post #1 is sold for using self shielding flux cored wire.

The gas conversion kit contains a solenoid gas valve, gas pressure regulator, hoses etc. to convert the machine for use with solid wire electrode that requires gas shielding.

[diarmaid]

Originally Posted by Weldtutor #1 Yes, I think he is! Again, you might ask him to demonstrate for you. You will probably learn all about aluminum wire "bird's nest" removal from the wire drive system using his method. The small diameter & very soft aluminum is very difficult to "push" satisfactorily with normal wire drive systems. Pull type MIG guns with drive rolls in the gun itself, or spool guns are the common solution to the above mentioned problem. #2 The machine mentioned in post #1 is sold for using self shielding flux cored wire. The gas conversion kit contains a solenoid gas valve, gas pressure regulator, hoses etc. to convert the machine for use with solid wire electrode that requires gas shielding.

Thankyou. I didn't realise some Migs were sold for only flux cored. Oh well, learn something new every day.

[DareBee]

diarmaid

Just so there is no confusion.
That machine is not sold ONLY for flux cored.
It is packaged to be inexpensive to get the home owners to buy it.
To keep the cost down they sell the gas kit as an "extra".
The machine is capable either way.

ALTHOUGH on a personal note I would NOT buy a 120V welding machine (accept for the backpack TIG (and they are often dual voltage)). They just dont have enough power and a Lincoln SP180 is only about $900 anyway.

[Tom Slick]

one thing not mentioned is duty cycle. on a tiny machine you'll have it cranked up to max and you'll weld 1 minute in 10. then you loose all the heat out of the area yet not have enough amperage to get the puddle going before gettitng the area too hot again. I recently had to weld some 1/8" wall 2x2 tubing with a lincoln 200a tig and the duty cycle wasn't enough to finish a 2" long pass.

[greg b]

The smallest mig we use on alluminium is 200amp unimig we have tried the small machines for fine work but they are hopeless, it appears .9to 1mm wire is ideal and i use a short lead with a nilon liner and a felt cleaner on the wire just behind the drive rollers.It is also good practice to only apply the minimum pressure to the drive rollers to avoid wire bunch up should your tips become blocked good luck with your with your choice of welders greg b

[tadream]

I have a customer that has been using Lincoln SP-100's for years to weld AL with decent results. Amazingly, they have found that the regular wound steel liners work better than the nylon ones, and they are pushing .035 wire with them. They are a sign contractor and are, of couse, only welding light gauge material with them. I was blown away the first time I saw one of their machines come in the shop, thinking they were idiots for trying to a) Push small diameter Aluminum, b) trying to weld it with a 115v machine, and c) using steel liners. Worse yet, they run them off portable generators to do roadside repairs. Once the machine was fixed, the guy brought over some of the material they were welding and proceeded to put down a decent bead with the thing. They've got about a half-dozen units set up this way and use them all the time. Keeping the gun straight and changing liners frequently allows it with very few birdnests. I have since been setting other people up with steel liners instead of Nylon or Teflon when pushing AL, with improved results. They do require more replacement or cleaning. I've also "engineered" a Lincoln spool gun onto a Century 140 amp mig (the guy INSISTED). It worked well also.

[jacarpen]

I have this same welder ( lincoln welpak 100hd ). I have purchased the "gas kit" as well as the "aluminum kit". I have practiced with it all weekend trying to weld some 6061 T-6 extrusion that is .160 thick. Sometimes it welds good, but I have not been able to get the "stack of dimes" bead to run. Most of the time it is either too cool or too hot and blows through the material. I am using 100% argon gas, but don't know for sure what to set the gas pressure on. I wish I had done more research before buying the add-ons for this welder. Any help on the gas pressure is greatly appreciated.

James