Cutting torch pre-heat blow-out

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Victor equipment.  Medium-size tip (well cleaned) on the cutting torch head.  New rubber O-rings on the cutting head where it seats in the handle.Problem: after the acetylene flame is lit and when I turn the valve to give initial pre-heat oxygen, I'm getting a small pop about once every two seconds.  This popping stops completely when I pull the extra-O2 lever, and the set-up then works fine for cutting.  Popping returns after I let the cutting lever off.The torch handle itself seals up nice and tight with welding tips - and no problems with welding tips.  Handle looks clean inside with no unusual carbon build-up at all.I started out using the actylene at 5-6 lbs, and the oxy at 25-30 psi at the regulator, for cutting with the medium-size tip.  I'm making sure the pre-heat flames are not 'jumped' off the tip.  In experimenting with the pressures at the regs, I'm sometimes actually getting a pre-heat flame blow-out, rather than stopping the pops.Is there a simple way to remedy this problem? .
Reply:How are you adjusting / setting the O2 at the torch?.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:Check the tapered seat on the top of the tip. You'll probably find a little nick/dent in it where it hit the floor when dropped.                                 MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Originally Posted by DSWHow are you adjusting / setting the O2 at the torch?
Reply:The main torch valve is usually all the way open. Then adjust the flame with the valve on the cutting handle. I'm not sure what size tip you are using, but 1/2" to 3/4" inner cones are way bigger than I ever set mine to. I would guess I set mine to about 1/4" on almost anything I cut. I forget the exact tip thats in the torch right now. I want to say it's for cutting 3/4" steel. Acet set at about 4-5psi, O2 at about 40psi..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:The problem you are having is caused by tip not seating correctly.The inner seat on the tip is not sealing properly.  When the preheat flame is light, and the cutting oxygen lever is not depressed, a small amount of mixed (oxygen & acetylene) gas gets by the inner seat of the tip and goes out the end of the tip through the center hole of the tip.  When the mixed gas reaches the flame it ignites, causing the popping sound, all of the gas in the center hole of the tip is consumed.  The leaking gas starts up the center hole of the tip agian and ignites with another pop.  The interval of pops will give an indication how much gas is leaking from the preheat to the cutting protion of the tip. It stops when the cutting lever is depressed, because there is now pressure in the cutting jet portion of the tip equal to the pressure leaking from the preheat side.  To correct problem, change tip  and/or make sure it is tighten properly.  (I see this problem with "gip" tip all the time.  I would recommend using only original Victor tips.)Have the torch head reseated by a gas apparatus repair facility.Hope this helps.JimOAdoctorwww.regulatortorchrepair.com
Reply:Originally Posted by DSWThe main torch valve is usually all the way open. Then adjust the flame with the valve on the cutting handle.
Reply:Okay, first thing I'll be doing is checking the tip (where it seats), and the seat in the cutting head (where the tip is attached).  Looking for possible defects that might cause leaks. Originally Posted by PookieIf you have a "popping" torch, and the problem is not with the seat of the tip, you are starving it.
Reply:Originally Posted by Joel_BCOkay, first thing I'll be doing is checking the tip (where it seats), and the seat in the cutting head (where the tip is attached).  Looking for possible defects that might cause leaks.Yeah, I want to ask you about this.  Would you suspect - given that I've been setting the O2 reg pressure at 30-35 lbs - that the "starving you're talking about would most likely be the acetylene pressure?
Reply:if you use a rosebud tip for alot of heating the regulators could be gummed upmiller maxstar 150   hobart handler 210 w mig conversion hobart 250 arc force plasma cutter    boston ind cutting torch miller performance auto darkening helmet milwalkee 14in chop saw 10,000 watt generator huge drill press and industrial band saw
Reply:Originally Posted by Pookie.      I am no seasoned pro here  The O2 knob on your mixing handle should be all the way open, as well as your cylinder valves should be all the way open.
Reply:Thanks for all responses so far.  I'm adding a very useful bit of info that I figured out today: My torch is popping in the pre-heat flame only phase with the Victor #2 cutting tip, but NOT with a Victor #1 (smaller-orafice) one.Both the #1 and the #2 appear to be in good shape. The #1 poses no problem. The #2 is actually a few years newer than the #1, but the #2 is actually only a few months old, and shows no dents or nicks, even under magnification.My acetylene tank is probably about 40% full right now, but still delivers the proper pressure according to the regulator gauge: setting reg pressure at 5-6 psi (with, of course, the torch valve fairly open while setting). The gas in the O2 tank is almost full up, at present.Does this info shed any light on the popping habit of the larger (but still quite medium-sized) tip?
Reply:Originally Posted by PookieIf you have a "popping" torch, and the problem is not with the seat of the tip, you are starving it.
Reply:Originally Posted by Joel_BCThanks for all responses so far.  I'm adding a very useful bit of info that I figured out today: My torch is popping in the pre-heat flame only phase with the Victor #2 cutting tip, but NOT with a Victor #1 (smaller-orafice) one.Both the #1 and the #2 appear to be in good shape. The #1 poses no problem. The #2 is actually a few years newer than the #1, but the #2 is actually only a few months old, and shows no dents or nicks, even under magnification.My acetylene tank is probably about 40% full right now, but still delivers the proper pressure according to the regulator gauge: setting reg pressure at 5-6 psi (with, of course, the torch valve fairly open while setting). The gas in the O2 tank is almost full up, at present.Does this info shed any light on the popping habit of the larger (but still quite medium-sized) tip?
Reply:Originally Posted by PookieAs long as the secondaries of your gauges are metering the flow, 40% full is as good as 90% full.  Given the tips are seated properly, and you aren't starving the flame, then the only thing left is that you are holding the torch way too close to the work surface on your pre-heat.
Reply:Originally Posted by Joel_BCThanks for all responses so far.  I'm adding a very useful bit of info that I figured out today: My torch is popping in the pre-heat flame only phase with the Victor #2 cutting tip, but NOT with a Victor #1 (smaller-orafice) one.
Reply:AODoctor is right #2 tip is BAD Try a new #2 tip
Reply:[QUOTE=Greg Lako;328957]AODoctor is right #2 tip is BAD Try a new #2 tip[/QUOTEThats the only thing I have ever found that causes the problem you are having. You can try tightening the nut holding the tip with a wrench. Sometimes the extra force will seat even a partly bad tip. The pressure/flow settings are very forgiving on most torch setups. A low setting on acct. can cause blowout and poping back, but not the kind of popping you describe.SA200,Ranger8,Trailblazer251NT,MM250,Dayton225AC,T  D-XL75,SpoolMate3545SGA100C,HF-15-1  RFCS-14 When I stick it, it stays stuck!
Reply:Have the Head Reseated and use a new tip.  JGSMAW,GMAW,FCAW,GTAW,SAW,PAC/PAW/OFCand Shielding Gases.  There all here. :
Reply:Originally Posted by OAdoctorThe problem you are having is caused by tip not seating correctly.The inner seat on the tip is not sealing properly.  When the preheat flame is light, and the cutting oxygen lever is not depressed, a small amount of mixed (oxygen & acetylene) gas gets by the inner seat of the tip and goes out the end of the tip through the center hole of the tip.  When the mixed gas reaches the flame it ignites, causing the popping sound, all of the gas in the center hole of the tip is consumed.  The leaking gas starts up the center hole of the tip agian and ignites with another pop.  The interval of pops will give an indication how much gas is leaking from the preheat to the cutting protion of the tip. It stops when the cutting lever is depressed, because there is now pressure in the cutting jet portion of the tip equal to the pressure leaking from the preheat side.  To correct problem, change tip  and/or make sure it is tighten properly.  (I see this problem with "gip" tip all the time.  I would recommend using only original Victor tips.)Have the torch head reseated by a gas apparatus repair facility.Hope this helps.Jim