Tips on better penetration?

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I have the northern tool 135 welder. I've been using it with flux core wire (.035) and have seen some made some nice looking welds. I'm pretty new to welding (about a year) and have only used the HF 90 welder in the past which I didn't realize how much it sucked until I got a better one. My issue now is that I got a little side job with a guy to do some light welding. Mostly 1/8" with an occasional 1/4" and I need the welds to look a lot better. In the past he's had me grind down all the welds to be flat so I didn't care if it looked nice or not, but now I'm doing a job where the welds will be showing and he doesn't want the welds grinded. So I figured I would switch to a gas setup with solid wire to make a better looking weld. This is the first time I've ever used a gas setup so I'm just practicing on scrap metal now. I'm using 75/25 argon/CO2 mixture and have it flowing at about 20 cfh. If any of you out there are familier with the machine I have the amp setting on 4 with the wire feed rate at about 3.2. The beads look nice after they are laid down, but the pieces will literally come apart with a slight push. I had the wire feed too high at first and I could peel off the bead with my finger nails after they had cooled. I got the settings so they seem right were it sounds like it should and isn't sputtering or jerking around but I still seem to have poor penetration issues. I could be wrong, but it shouldn't be too difficult to blow a hole through 1/8" steel with 135 amps, right? At one time I tried to burn a hole through a piece of scrap and just got a giant blob about the size of a gumball. I've tried thouroughly cleaning the metal and ground location before welding, I've grinded down chamfers on the pieces of steel, I've tried adjusting the flow rate of the gas, changing the polarity, using .035 and .030 solid wire, and using different outlets. The only thing I can think of is that it's the power source. I've been running it off a 25' 14g etxtension cord from an outlet I installed myself, but I tried plugging it into a pre-existing outlet and got a slight increase in power (had to change wire speed to about 3.5) but that was it. Still not much better. Any tips on how I can get better pentration with the gas setup or do I have to go back to flux core?
Reply:Adding gas to the mix ie. switching from FCAW to GMAW with this tiny machine reduced your avaliable penetration by 25%Adding bevels or gaps in the joint is what needs to happen.
Reply:Hello Econdron, in addition to what Fat Bastard included for information, you may wish to check to be sure that you are operating on the correct polarity. When you make the switch from self-shielded fluxcore wire to a gas-shielded solid wire you need to be operating on the opposite polarity or, Reverse Polarity (gun +, ground- ). I think I have some interesting images of incorrect polarity for gas-shielded solid wire that may be of interest. Another thing that will help when you are using solid wire on a smaller machine like that is to use a grinder to remove all of the mill scale and rust that is in the area of your welds. You may already be aware of all of this, yet if you aren't, these are a few other items to consider. Good luck and best regards, Allan Attached Imagesaevald
Reply:Interesting images there Allan.Picts of your welds would also help. 1/8" is pushing that little machine to the max under practical real world conditions no matter what the manufacturer might say. .035 solid wire is probably too big for that little machine. I'd be running .030 wire instead. Proper prep, as mentioned above, is also critical when you are maxing out the machine.With mig the closer you keep the tip to the work, the "hotter" the weld will be with the exact same settings. I see a lot of newer and inexperienced welders trying to weld with to long a stick out with mig because they don't know how to hold the gun and see whats going on. With solid wire you generally push, so stand where you can see down the barrel of the gun and weld roughly towards you, keeping the tip of the gun roughly 1/4" from the work. If you are holding 1/2"+ with that machine you'll never get decent results no matter how pretty the beads look.As far as material thicker than 1/8", you won't get decent penetration even with good prep and flux core with a 110v machine. It's simply beyond the power capabilities that you have available.You've honestly just run into the big problem with 110v migs. They don't have enough input to do more than sheet metal under real world conditions. It's even worse if you starve them of power using an undersized extension cord and a 15 amp breaker. To even have a chance you need to be on a dedicated 20 amp 110v line.  You wouldn't probably be having as many issues ( unless you have the polarity backwards) with a bigger machine. Yes they are not as "portable" because 230v power isn't as readily available, but that's why guys that do portable work have engine drives or run gen sets to get the power they need to do heavier mig..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Hello Doug, liked those eh? There's kind of a funny story behind these pics. But first, you may have noticed in the picture that you can still see the soap stone line that the student was using for a guide to help with bead straightness, these were run vertically in a downhill progression. He brought them into the office for critiqueing and to ask about the lack of fusion that he had noticed along the toes of the welds. I first asked him about his machine parameters thinking that he was just simply well under the voltages/wirespeeds that he should have been running. Oddly enough he told me that he was running around 23 volts and 4 1/4 on the wirespeed (feeders have 1-10, not ipm), anyway, seemed to be in the ballpark. These were done with 75%Ar, 25%CO2. Then I took my fingernail and peeled up the one bead as you see in the photos. Next I went out to take a look at the machine and give it a run. The moment that I pulled the trigger I noticed something definitely wrong with how it welded. Took a quick peek at the machine/feeder set-up and noticed the polarity. Another individual had been using the same machine (XMT 304/S22A feeder) before him running gasless fluxcore and when he switched it over he didn't pay attention to the polarity. Once we got the polarity correctly connected there was a world of difference in how the machine performed. A little bit off topic but could save someone a little bit of a headache down the line. Best regards, Allanaevald
Reply:Astroglide and consistent hip..... Nevermind wrong kinda penetration.
Reply:The lack of penetration is due to the extremely limited current output of your machine. No getting around it.Unless you're welding, say, 16 ga, you're not going to penetrate much of anything with those 115v Chinese-made doorstops. The best solution is really to buy 220V machine with twice as much output current. Adding about a 3/32" gap may help you with 90 degree fillets. I would advise you not to weld materials thicker than 10 ga, if you can help it. Going past 1/8 in is frankly irresponsible.Switch to .023" solid wire...if you can find .023" tips/ guides/ feed rollers for your machine. I believe you can buy the .023" parts online or have NT order them for you. This will produces a smoother, more consistent arc, with better weld fusion. It will also force you to slow down thus increasing the heat input per inch of weld.Last edited by Joshfromsaltlake; 07-17-2012 at 07:39 AM.
Reply:Maybe running 100% CO2 would help a little also. My LWS recomended me to run CO2 with my HH120 because of this issue. Even with that, it still not as much penetration as with flux coreSafety 3rdGump
Reply:Any good LWS should have some of this on hand to help with penetration. "Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by usmcruzAstroglide and consistent hip..... Nevermind wrong kinda penetration.
Reply:You guys are sick! lol Thanks for the input. I'll star rubbing astroglide on my metal before welding! lol So I'm thinking of buying a new welder. I'm looking at the NT 200 MIG/Stick hybrid welder. It's got good reviews on the website. Anyone use this or hear anything about it? I love the USA but can't afford their products!Also, any tips on getting a 230V outlet in my garage? Am I able to just make a new outlet from the wires going to the dryer? (It's like 10 feet away) or should I get an electrician to do it and how much would that cost? (I live in Illinois) Also, where can I get a 230V extension cord?
Reply:I'll star rubbing astroglide on my metal before welding! lol
Reply:You have 2 options for 220 extension cords, 1 is to make one and the the big box stores like HD or Lowes would have what you need.  And the other choice would to buy one premade and the LWS might have one in stock or at least be able to order one.Ron