Having an impossible time welding with OA setup

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Hello all, this my first post and I hope its not considered rude to start up a thread but I could really use some help.  I bought an OA setup relatively recently (medium duty victor "performer").  I use the acetylene regulator that came with it but I have a separate two stage oxy regulator.  Anyhow, I have gone through basically half a tank and am yet to get a weld that even approaches acceptable.  I am not doing anything fancy, just trying butt weld some 1/8" plain jane mild steel.  I beveled the edges ~60 degrees and sanded them nice and clean.  The flame looks fine and adjusts nicely, no pulsing or anything, with a definite dark streak coming off the tip of the cone, seems like a textbook neutral flame.  I get a puddle going and it sparks and foams a little, and when I add the filler rod to the mix it has a tendency to spark foam and froth like its rabid.  I tried two different rods from two different manufacturers so I doubt thats the problem.  I finish making the weld, let it cool, put it in a vise and use some pliers to try to test the weld.  It just snaps, every time, with nowhere near as much force as it should take.  I'm pretty sure epoxy would make a stronger bond.  The weld bead itself snaps right down the middle and looking inside it seems like its massively contaminated with air pockets.  I've tried with a neutral flame, a 1x reducing flame, filler rod, no filler rod, larger tip, smaller tip, even a totally different torch (henrob).  Result is always the same.  I am starting to feel like I am part of some big conspiracy lol, like OA welding isnt even a thing and everyone is aware of this except me.  I realize that I am grasping at straws, but the only thing that has remained constant are the gas tanks, so I am growing suspicious that one or both are somehow contaminated.  Is that possible/been known to happen?  I am getting to my wits and wallets end and would greatly appreciate any insight anyone could give.
Reply:the puddle should not spark and foam.look online for ana rticle by budd davidson called zen and the art of the weld puddle.  look on the tinmantech site for a description of how to set up your torch.when its working for me, i have a soft flame..not a "pressurey" flame..better too large a tip than trying to get too much from a too small one..
Reply:You are using acetylyne right, not propane, proplyne or MAPP.  A picture of your flame would help.  If you have a flame that is hissing and making a lot of noise you are out of adjustment.Dan
Reply:Hi voelln, welcome to the WeldingWeb!It's pretty difficult to master oxy-acetylene welding by yourself.It's hard for me to pick up on what you might be doing wrong by reading your description.Sounds like overheated and oxygen in the weld metal... but that's a guess.Honestly, you would best be served by having someone local give you a hand.Maybe showing your city/state in your descriptor would help; there may be a member here is only a few minutes away from your home who could help resolve your problem... face-to-face.Wish I could do more...Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Foaming is a bad indication, you are getting porosity that creates all the holes in your weld. Only a neutral flame will create the CO2 that you need to shield out O2 from the air. My best guess is that too much fuel, (if memory serves), is present in the flame. You must set up the torch correctly, nothing less will do. Because when it works, torch welding is as easy as it gets. Just not on thick material! If I want to weld 1/8" to 1/8" mild steel. I open the O2 valve all the way, and the acetylene valve  maybe one turn and a half. Taking one gas at a time, I set the gas flow rates, by opening the torch valve for one gas, say O2. Then turn in the adjuster knob at the O2 regulator until I see about 5 cfh. Then shut off the torch O2 valve.Then I open the acetylene torch valve. Next, I turn in the acetylene regulator adjuster knob until I get about 5 cfh. Then shut off the torch acetylene valve. The torch is now set for gas flow rates. You want an appropriate sized tip for 1/8" steel. With my Victor torch, I use either a size 1 or size 0 for most small jobs that I torch weld.  Fire up with a small amount of acetylene until the flame starts to feather out. Add O2 until I get a sharp pencil tip sized blue flame, SHARP! I like to go a little bit past sharp, then back down again to be certain it is as sharp as possible. Keep an air gap of 1/8" between the blue flame tip and the work piece. AIR GAP 1/8 INCH!!! Sparks are a good sign, foam is a bad sign. The puddle should throw occasional sparks. If your fit up is tight, you don't need filler right away. Puddles take time at first, just wait.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:tanglediver, i thn k you mean  psi not cfh..but the problem with setting a welding torch by the gauges is you are meaasuring whats  coming out of the regulator not whats at the tip.the hose can  restrict  flow quite a bit, so the tip that works well with a 5# gauge setting and 20 foot of hose wont work with a 5# setting and fifty feet..if you light the acetylene  side of the torch  and open the torch valve wide, you can use the regulator to get the max flow for the tip(just where the flame  leaves the tip and back off a red hair, without looking at the gauge ),then the same with the ox side, now the regs are set for that tip with that hose.... then use the torch valve to adjust the  flame down to where it makes the right welding flame..you want to get a puddle but not blow it around..Last edited by weldbead; 03-23-2012 at 04:23 AM.
Reply:Voelln, this is all good advice you have received in the above info.  However, seeing as you do not have an experienced teacher with you, the next best thing is a book on this subject.  I will recommend two of the best out there: THE OXY-ACETYLENE HANDBOOK by LINDE REFERANCE LIBRARY and AIRCRAFT WELDING by L.S.ELZEA.  This book can be purchased thru Lindsay Publishing at a very reasonable price.  The first book may be a little harder to find, you might try Amazon. Also, The Tinmantec web site as mentioned above by Rickv.  The books I mentioned all give lessons with pictures so it is easier to learn.  Hope this helps you.  Bob
Reply:Likely your torch is too far away and the surrounding oxygen is reaching the weld pool.  This is very common with students starting out.  The little neutral cone flame must be about 1/8 above the surface of the metal.  If you are 1/4 inch or higher the steel starts to "burn"  The large envelope of unburned gasses next to the small cone is what shields the weld pool.
Reply:Foaming and sparking in the weld puddle means you are boiling the metal - you are too hot.An OA puddle should flow with very little sparking.  Try making the puddle on a flat piece of 1/8" sheet and adding filler to that to get a good bead.  Move to the joint when you can control the puddle.Watch your tip size an gas pressures too - a butt joint can sometimes go one tip smaller than the victor chart, depending on your technique.  Other joints (think fillet or mismatched parent metal thickness) might want a larger tip.Don't be afraid to try different distances from workpiece, different tips, even vary the gas pressure a bit - the key here is to experiment and find the sweet spot of the setup that matches the way you weld.I can strongly recommend the OA Welding DVD at Northern Tool - I know a bunch of folks (me included) that leaned heavily on that video to get my feet on the ground with OA welding.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:First of all thanks for the responses, its nice to see this is an active forum.  One thing I should have mentioned in the opening post was that when I remove the flame from the puddle and watch it cool I can see it "cauliflowering".  The surface mushrooms and bubbles up a bit like rust under a paint job.  I take this to mean there is a ton of dissolved gas in the puddle that tries to escape when it cools but cant quite make it out because the surface hardens too quick.  This happens basically every time, even if there isn't much foaming going on during the melt (holding the flame closer did cut down on the foaming quite a lot).  I hadnt really considered that my flame might be fuel rich, I just assumed foam and sparks meant too much oxy, so I will give that a shot.  Admittedly I've been a bit of a nervous nelly with holding the flame close and using enough oxygen since my first experience with a backfire caught me off guard and nearly emptied my bowels. (I was fooling around with a rosebud and turned the oxygen up too high and BANG  )Anyhow, thanks for the tips all.
Reply:I agree with the information above and would add that you need to keep the hot end of the filler within the protective part of the flame when not dipping it into the puddle; getting it too far away allows the surface to oxidize and then that gets added to the puddle. Oxygen in the puddle can combine with any carbon present to form CO which will remain dissolved until the metal starts to cool, causing the bubbling. You would find it easier to practice running a small bead across the face of a small test piece rather than beginning with a joint. I'd also suggest being sure it's mild steel, not some higher carbon material. I would suggest also checking your local library to see if it has any good welding books. Some of the older ones were quite detailed.
Reply:Just a comment on your worry about flashback.  One of the un-sung functions of the oxygen is to keep the tip cool.  You really want to set the regulator pressures (and hence, flow rates) of your fuel and oxygen are supposed to be for the specific tip you are using.  If you add flashback arrestors, check valves, narrow or unusually long hoses, these can slow the flow and increase the risk of burn back into the tip.  YOu need that gas flow to move heat out of the tip metal to keep it cool.As for your problems, I almost spit my coffee out laughing when I read your conspiracy theory.  I still have moments where feel that way  .  Start with a regular size coupon (say 4"x6"  1/8" thick mild steel) held off the table by a pair of fire bricks and just learn to run puddles back and forth, then move on to adding filler rod.  When you get a half dozen or so good beads built up that are straight, even width, good tie in at the toe, and good penetration, then you've got the control down for the butt welds, and on from there.Good luck!