Power Tig 185 Dual Voltage / my first time welding

[CMJ]

This is the first time I have ever used a welder. I was practicing on 1/8 steel and 1/8th aluminum plate on 120v. I was having a tough time with the steel and did not realize that although I was using the pedal it was only acting as an on off switch. I accidentally had the switch set to panel and was getting aver 100 amps.

I corrected the foot pedal issue and tried out some aluminum. This was weird, it has a much different sound that dc and is a lot louder. I could not get a good arc unless I flat footed the pedal. Any thing less than 100% pedal and acr seemed to go everywhere but the aluminum with lots of popping. At full pedal every thing was fine, and I could back off once the aluminum started to flow. I did my best to keep the tungsten about 1/8th from the base metal. The third picture is aluminum. Can you guys give me some pointers?

The title should be power tig 185 not 180, can a mod change it please?

[jakeru]

Typical advice for stabilizing an A/C TIG arc applies: Go down in tunsten size, go sharper on the preparation of your tungsten tip, or go up in current to stabilize the arc (or some combination of the above.)

The arc will be most stable, (and directional) near the higher end of a tungsten's current carrying capability. Every tungsten has a range of current it can carry with stability, you are probably just too low on that range. It's typical for a newbie to start out not running enough current.

From your pictures, it looks like you have a good, inert shielding environment (which is good to rule out as a potential culprit of the unstable arc.)

Check out this chart published by a manufacturer of TIG torch components:
http://www.ckworldwide.com/tech-3.pdf

According to that chart, an .040" tungsten size is ideal for a current range of 15-80 amps. So that would probably be ideal for the way you are probably approaching your first aluminum welds. I almost never use an .040" tungsten though, I usually just sharpen my 1/16" to go low on current.

1/16" tungsten size, 70-150 amps. I use this a lot on my super200P. I can make it work as high as 200 amps with a blunt tip, 2% lanthanated, minimum A/C balance, and a little helium mix.

3/32" tungsten size, 140-235 amps. I rarely use 3/32.

1/8" tungsten size, 220-325 amps. I never use 1/8".

Of course, you can bias those numbers lower or higher, depending on how sharp you grind the tip. Sharper tip = lower current range, blunter tip = higher.

You will know if you've overloaded a lanthanated/ceriated/thoriated tungsten tip if you melt it. If you haven't melted the tip, there is still current yet left to go.

A/C balance is important to set right. I like 20% EP for clean aluminum; it's the minimum that my machine can do.

With an appropriate starting current setting, you'll make a puddle in about 3 or so seconds. Then lift off the pedal to maintain a consistent puddle size as you progress the bead. Significant lifting will be necessary approaching an edge of the workpiece. At the end, try to lift up on the pedal so much that the puddle has completely or substantially solidified before the arc actually terminates (this will get rid of the crater at the end.)

[undercut]

Very informative post, jakeru. Thanks.

[Rambozo]

The steel looks a little overheated like your travel speed was too low. That is to be expected as you are starting out. Your pedal issue also explains that. A lilttle more practice and you will get that sorted out. The aluminum looks a little cold. I think you might be asking a bit more than your machine can deliver using 120v. If you switch to 230v I bet that will take care of things. For a first attempt, it looks very good, to me. I would suggest that you try to keep the tungsten a little closer to the puddle, 1/8" is a little far, at least for steel. Try to cut that in half, if you can. You didn't mention your tungsten size, or other settings, but you are obviously in the ballpark with them.

[everlastsupport]

The aluminum looks a little cold. I think you might be asking a bit more than your machine can deliver using 120v. If you switch to 230v I bet that will take care of things.

Ditto on your whole post, but the 230vac I used to repeat daily on the phone.

[Zmechanic]

In that aluminum picture you posted, I can see some aluminum beads on the top and bottom that you didn't photograph. The one on top looks very close to the right amount of heat, actually. You don't want the puddle to look like it's just standing up on top of the base metal, you want it to look like it's part of the metal.

[CMJ]

Thanks for all the info guys. I'm using 3/32 tungsten with a gas lense, so the size might be one of my issues. I got a lot of warpage on the both the steel and aluminum. I plan crawling under the house next weekend to see if I can tap into my unused 220/50amp dryer line.

[Zmechanic]

Your tungsten is fine. I seriously use a 3/32" tungsten for almost EVERYTHING. If I was doing super thin stuff, I might knock it down, but really the only time I would is if I was very concerned about low amperage arc stability.

Running a straight bead across a piece of flat metal will warp the hell out of it. Think of attaching a cable to the extents of the weld bead and tightening the crap out of it. That's basically what you are doing.

[Rodsmachineshop]

what i have learned with 110 v welders is they weld crappy unless you have a dedicated 110v outlet and wired with 12 gauge or thicker wire with 20 amp outlet . a 15 amp outlet with 14 gauge just wont cut it . I had a couple of 110 welders at my old shop in California and had my 110v wiring all in 12 gauge they worked great

[fdcmiami]

Your tungsten is fine. I seriously use a 3/32" tungsten for almost EVERYTHING. If I was doing super thin stuff, I might knock it down, but really the only time I would is if I was very concerned about low amperage arc stability.

Running a straight bead across a piece of flat metal will warp the hell out of it. Think of attaching a cable to the extents of the weld bead and tightening the crap out of it. That's basically what you are doing.

first to the OP, nice work for your first time. it looks real good, keep at it. i am on board with that 3/32; if you were working in a shop and asked the boss for some .040 or even .060 to tungsten to weld some 1/8 th Al they would look at you like you were weird. i also do most of my work with 3/32 and a lot of it with 1/8 th. i have a tungsten grinder in my tig kit, if i want to grind .040 with it i'll have to special order the attachment to do it.

[Rambozo]

what i have learned with 110 v welders is they weld crappy unless you have a dedicated 110v outlet and wired with 12 gauge or thicker wire with 20 amp outlet . a 15 amp outlet with 14 gauge just wont cut it . I had a couple of 110 welders at my old shop in California and had my 110v wiring all in 12 gauge they worked great

Trying to weld aluminum with a 120 volt welder is just not easy no matter what. Pre-heat like crazy and have a good circuit. Much better just to switch to 230 volt, since you have that option.

The Hobart rep that would come by my old shop to demo new welders had an interesting cheat. He would run them off a generator that was set to over 150 volts on a 30 amp circuit. Makes any welder look a lot better.

[CMJ]

What is the technique for welding thin steel to thicker steel? I have some ~1/16 stainless an I tried to make a T joint with some thinner stainless that was around 1/32. I kept blowing through the thin stuff. I tried to ride the pedal and give less amps as I moved over the thin stuff, and that helped, but then my 1/16 filler rod would stick or just ball up and look like crap.

[Rambozo]

A general rule of thumb is to use filler rod that is the thickness of your material or less. This is because it might take more current to melt the filler than the base metal. What you describe is possible, but it will require skill to pull it off. I would get some .040" filler to make things easier. But any kind of thin welding takes practice. If you concentrate the heat on your .062" part, add the filler there, then wash the puddle up to the .030" part, you could produce a good weld. I would say start with .125" material, then .062" before trying .030.

[CMJ]

I started to build a small welding table. Are these welds looking alright? It's a 1/8 plate with 1/8 L pieces.

[KSmith]

I started to build a small welding table. Are these welds looking alright? It's a 1/8 plate with 1/8 L pieces.

The only thing I could suggest to make better welds is to clean the metal a bit more, down to shiny steel. Things will go alot better that way.

ken