Trying to get the flame & technique right

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I am practicing my Oxy/Acetylene welding with 1/8" coupons and 1/16" filler rod. So far my edge is good but I am having trouble with my laps (flat position). Tonight I tried some different flame adjustments and I believe I am on the right track. At first I  couldn't keep the puddle fluid unless I turned up the oxygen till it would hiss slightly. This melted the metal fine but the pressure from the increased O2 was blowing my bead around and making it sloppy and full of holes. Finally I increased the Acetylene more and adjusted the O2 till just before the hissing point. It made a difference in that I can now keep the puddle going without blowing it all over the place. It is still difficult for me to melt the bottom piece into the top piece while moving along and applying filler, sometimes I can't tell if there is a good puddle melted into the work or if it is just melted filler laying on top of the work. I am directing the tip mostly into the bottom piece, only slightly angled toward the top piece. I get both pieces to melt, but there is a small part right where they join that doesn't want to melt until the puddle is quite large and starting to get hard to control. I am using a #1 tip on my Harris setup. Any tips would sure be appreciated.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:Look through the O/A sticky,or http://www.millerwelds.com/resources/articles/search/ on how to balance your torch, choose a tip, what a neutral, oxidizing flame and carborizing flame is and their relative heat outputs and consider buying the student pack.Post your pictures for reveiw.
Reply:If the gas pressure is blowing your bead around then you might need to move to a smaller tip.The key to adjusting the flame is to understand that your goal of a neutral flame is to ensure that the oxygen and acetylene are BOTH fully consumed.  Excess of either will probably injure your weld.  - Put on your goggles before lighting)- Set the pressure on the tanks using the manufacturer recommendation for the specific tip- Light the acetylene first (no Ox) and adjust until you just stop seeing soot from the flame- Add oxygen until the secondary cone merges with the small inner coneThe cone that is left should be kept out of the pool and off the filler rod (otherwise it will pop and blow the puddle away)When choosing a tip, start with the mfg. chart for metal thickness.  For inside corners you will need a larger tip, for small butt joints you might go smaller - the issue is how much heat the workpiece absorbs which alters the rate at which the puddle melts.Hobart LX235Victor 250 Oxy-Acetylene Rig (welding and cutting)Bobcat 773F-350, 1999, 4x4, 16' 10K# trailerOutdoor Wood Burner - 10 cords/year
Reply:OK I did some more research and I was surprised to learn that the Harris numbering is way different than the Victor system we have at school. (I am taking OA and stick at our community college). We have been using "0" and "1" Victor tips. According to the Harris chart I need a "3" for my 1/8" coupons. Tonight I tried a "2" and a "3". The "3" seemed to burn in nicer, in fact I had a hard time keeping up with the filler, I should have switched to 1/8" filler but I didn't think of it, I was using 1/16". I knew the numbering was different but I thought it would be close. WRONG!So with the "1" tip I must have been really pushing the pressures to get more heat which pushed my bead all over and blew holes in it?Here are some pics:Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:What changed between the last two welds/photos?
Reply:You know what I would suggest you do to help you improve your technique and get you on the right heat setting and pointing the cone where you want it, would be to take some chits and practice running beads without any filler by heating and maintaining a puddle from one end to the other end before using filler(watch your puddle form and crawl along), or even do it on the side before practicing your laps.Your technique shows inconsitent heating.You should be able to get good enough at this to do the lap without filler, you may have to focus on the top peice a little more.I remember learning way back in the day doing sheet metal without any filler or just at the start with very little training.
Reply:Hi bigb, I started an Ox/Acet course two weeks ago... so I am no expert At the college, all 20+ welding booths are set up with Harris torches and #3 tips - and we have been working on 1/16 inch thick steel coupons.  Yes, so I imagine that a smaller Harris #1 tip on metal twice as thick (your 1/8 inch) was a bit of a mis-match.Week 1 - Weld PuddleJust learned to recognize the liquid sheen of the weld puddle and practice moving slowly along the coupon (1 inch x 3 inch) in order to bring the puddle with us.  We used a neutral flame with cone tip maybe 1/4 inch from the surface of the coupon.Week 2 - Corner JointsLearned to tack weld the two edge/corners of two coupons placed in an 'L'.  Then we practiced melting (weld puddle again) the edges together to form a weld bead along the 3 inch length of the coupons.  We used a neutral flame with cone tip maybe 1/8 inch from the surface of the coupons.Week 3 - Fillet rod and T joints?  That's Next Week.  So I can't 'fill' you in Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Originally Posted by tapwelderWhat changed between the last two welds/photos?