OA welding questions

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I am trying to weld 16 gauge sheet today, just for fun and learning. I have a relatively new Purox metalmaster setup, and the tip sizes are measured in cu ft of gas flow. So I am thinking the #4 tip is approximately equal to a victor 0, the #6 is roughly equal to a victor #1, and the #9 tip is roughly equal to a victor #2, and so on.I have Steve Bleil's video, and have watched it a number of times. I also have Finch's Welder's Handbook, the ESAB's Oxy Acetylene Handbook. Despite the resources, I am having the hardest time trying to get the hang of this. I have tried all of the tip sizes mentioed above, and I have the gas pressures set as per the owners manual. I can't seem to get a decent puddle going. The metal seems to go from too cold, barely liquid and not nearly hot enough to dip the welding rod, to way too hot, in an instant. I have tried changing torch angles, tip sizes, gas pressure, etc. I am kind of out of ideas. This is the same if I am trying to use a filler rod or if I am just trying to run a puddle across the sheet. Always too hot (sparks, buring through, torch pop) or too cold. I can't seem to get the happy medium. My questions:1. I can't seem to find any community college or adult ed  classes in Connecticut that offer a welding course. Anyone here from CT, and can point me in the right direction?2. Are there any other good books/videos that I should get?3. I know I need to keep trying and practicing, but if you have any tips or tricks you can suggest, I am all ears.Thanks in advance.
Reply:Louie, The 4 is the same as a Vic0, the 6 is the same as a Vic2, and the 9 is between a Vic2 and Vic3. For your material thickness of about .060", the number 4 tip would be my starting point. 1-Light the torch, acetylene only, and open the valve just until the pure acetylene flame stops sooting and becomes slightly bushy yet still attached to the tip.2-roll on the oxygen to a neutral flame with just a tick of a feather.....this is your starting flame setting for the tip size.3-Keep the inner cone about 1/16-1/8" from the work, tip angle of about 30-45 degrees.4-Form the puddle first, adding filler by letting the puddle melt the filler off.If the puddle is moving too fast for you, back the flame off by closing the acetylene until you have a 1/2-3/4" feather, then closing the oxygen back to neutral. We call this stepping the flame. By following a common startup method, and using steps to adjust the flame, one can quickly re-light the torch and get back to the flame size that was working well before. Good habbit to get into.
Reply:Two books I recommend:  The OXY-ACETYLENE HANDBOOK by Lind (Union Carbide) and AIRCRAFT WELDING by L.S.Elzea.  The first book will be a bit harder to find.  Hope this info helps you.  Best  Bob
Reply:Another good read is The Oxy-Acetylene Weldor's Handbook by T.B. Jefferson.  It used to be available at Sears, and can be found on Abe Books or eBay.
Reply:Originally Posted by rhuntTwo books I recommend:  The OXY-ACETYLENE HANDBOOK by Lind (Union Carbide)
Reply:search  " zen and the weld puddle "  ....wont hurt a thing..
Reply:Couple of things especially for starting off at the beginning. 16 gauge is pretty thin and it's going to do exactly as you are experiencing - once it gets to melting, you gotta move quick and move your torch to control heat.  That can mean circles or half moons, and it can also mean pulling the flame back a bit, and it can mean moving forward.All the references mentioned are good ones.How are you set up?  Start with a decent size coupon laying flat between two fire bricks, so you are welding where there's air underneath.  That will really help keep the heat from building up as quickly by having air flow around it.  Then start in the MIDDLE with a circle motion about 1/4" diameter, slowly heating it up till it starts to look a little plastic and starts to get a "wet" look. The torch, as said, should be about 45 degree angle or maybe a little more straight up and down.Then start moving that spot around by making your circles a little off set.  The spot isn't really moving, it's just the location on the coupon that happens to be melting.  Just drive it all over the place leaving snail trails.  lifting the flame a bit to let the puddle cool a bit.  The direction you move the puddle is the direction the flame is pointing, btw.Nothing wrong with backing off (lifting the flame up) and letting it solidify as long as the cooling area remains in the gas envelope of the flame to protect it from oxygen.One other thing, if you are popping the puddle it can be a bit too hot, so get moving or back off a bit.  Also, clean steel rather than milscale covered hotroll helps with contamination and with heating up.  The milscale absorbs a lot of heat.Hope that helps a bit.
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Reply:Originally Posted by RodJCouple of things especially for starting off at the beginning. 16 gauge is pretty thin and it's going to do exactly as you are experiencing - once it gets to melting, you gotta move quick and move your torch to control heat.  That can mean circles or half moons, and it can also mean pulling the flame back a bit, and it can mean moving forward.All the references mentioned are good ones.How are you set up?  Start with a decent size coupon laying flat between two fire bricks, so you are welding where there's air underneath.  That will really help keep the heat from building up as quickly by having air flow around it.  Then start in the MIDDLE with a circle motion about 1/4" diameter, slowly heating it up till it starts to look a little plastic and starts to get a "wet" look. The torch, as said, should be about 45 degree angle or maybe a little more straight up and down.Then start moving that spot around by making your circles a little off set.  The spot isn't really moving, it's just the location on the coupon that happens to be melting.  Just drive it all over the place leaving snail trails.  lifting the flame a bit to let the puddle cool a bit.  The direction you move the puddle is the direction the flame is pointing, btw.Nothing wrong with backing off (lifting the flame up) and letting it solidify as long as the cooling area remains in the gas envelope of the flame to protect it from oxygen.One other thing, if you are popping the puddle it can be a bit too hot, so get moving or back off a bit.  Also, clean steel rather than milscale covered hotroll helps with contamination and with heating up.  The milscale absorbs a lot of heat.Hope that helps a bit.
Reply:Thanks for all the responses. My set up is that I have the coupons suspended in air, after tacking them. I use some angle iron to hold them up off the bricks. I wonder if I would be better off starting with something thicker than 16 gauge sheet?  I have in fact tried backing the torch of and changing torch angles. All of my steel is thoroughly cleaned and mill scale ground off with a sanding flap wheel.As far as my flame, I believe I have a neutral flame. I am opening the gas first, adjust to get a feathered flame that almost but not quite quits smoking, and not pulling away from the tip. Then I add O2 just until the inner and out cones come together. If I were to add a little more O2, the sound will change and become more harsh. I make sure I don't go that far, so as to avoid an oxidizing flame. I am trying to keep the inner cone close to but not buried in the puddle. I actually only had the torch pop twice in my last session. but the puddle is overheating and sparking like mad.
Reply:I will try some more after work today, maybe with some thicker material.
Reply:Originally Posted by makoman1860Im going to counter some of the above advise, on the basis that the one particular technique can get you in trouble and is not one of the best habbits.If things are getting too hot, and too fast, instead of pulling the torch away ( which does reduce the peak temperature, but also widens the heated area ), roll the torch over so the flame is more parallel to the work surface. Use the torch angle to control heat input, always maintaining the 1/16-1/8" distance from the inner cone to the work. When doing structural welds on light tubing, you are always on the verge of disaster in order to assure 100% penetration. If you get in the habbit of backing the torch off, you will find it can get you in trouble in a hurry. Same goes for aluminum welding.....never EVER back the torch off the work.
Reply:Let me know how you like it. Pulling the torch back is one of those things I discourage, mainly for materials other than plain ol' steel, but I have found is a hard habbit to break once learned so I discourage it all together. I think the method you are describing with the torch movements is what I call "scale welding". Deffinately useful for sticky spots, and also used when bronze welding steel.
Reply:I havn't noticed anything about the diameter of the filler rod.  A larger rod can be used to take away heat as well as to add filler material.If you put the steel pieces in a vice and bang over a bit at a right angle then put two of them together and melt the banged over sections perhaps in the range of the metal thickness instead of using a rod for filler it might be less frustrating.  Or you can try keeping the rod in the puddle and stirring as described in the oxy acetylene manual.  If you are cost concious I would suggest staying as thin as possible as fuel use can go up rather dramaticly as metal thickness does.
Reply:Originally Posted by fran...k.I havn't noticed anything about the diameter of the filler rod.  A larger rod can be used to take away heat as well as to add filler material.If you put the steel pieces in a vice and bang over a bit at a right angle then put two of them together and melt the banged over sections perhaps in the range of the metal thickness instead of using a rod for filler it might be less frustrating.  Or you can try keeping the rod in the puddle and stirring as described in the oxy acetylene manual.  If you are cost concious I would suggest staying as thin as possible as fuel use can go up rather dramaticly as metal thickness does.
Reply:Originally Posted by makoman1860Let me know how you like it. Pulling the torch back is one of those things I discourage, mainly for materials other than plain ol' steel, but I have found is a hard habbit to break once learned so I discourage it all together. I think the method you are describing with the torch movements is what I call "scale welding". Deffinately useful for sticky spots, and also used when bronze welding steel.
Reply:Originally Posted by RodJAs soon as I can get a few hours of peace and quiet around here, I'm going to try it.  Too many dogs, cats, chores, neighbors dropping by, etc. I need to get up around 4:30 am on a sunday and work.Question, why do you call it scale welding?  Also, I haven't welded anything but steel. What makes the pull up technique (wow, that sounds eerily close to the Catholic church) particularly bad for non-steel welding?Thanks again Makoman.