Rosebuds and 1/7 and or 1/10

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I've read about the 1/7 slash 1/10 rule here, never heard about it any where else. Has anyone ever actually seen this be a problem, is it a real world safety issue (acetone spitting aside, since from what I've read here that's not really a safety problem)..Or is it just one of those hypothetical safety topics that goes on forever like pi?I'm new to using a rosebud, getting into some forming of steel trying to do some aesthetically pleasing fab work, and wondering if this is something to lose sleep over, or just chuck into the "might get struck by lightning" category.Input from old timers who have been there much appreciated, as I said, looping theoretical discussions give me the clap.THX
Reply:bellflowerYou have identified the 'Holy Grail' of O/A confusion.Acetylene delivery is a chemistry constant, not a rule, i.e. behavior or training.The popularly quoted acetylene rule is actually a ratio. The lay/liberal word usage of rule, only fosters confusion in new learners.  bellflower  -  Clear, immediate, and applicable understanding of O/A can only be found in a book  -  original reference source.To:  Senior O/A Practitioners -  what are your favorite references to answer bellfower's questions?OpusLast edited by OPUS FERRO; 07-09-2013 at 02:06 AM.
Reply:The Oxy-Acetylene Weldor's Handbook by T.B. Jefferson.  Out of print, but available.Lindie put out a similar book which is also out of print, but available. From ESAB's site:"With acetylene, the recommended withdrawal rate on a continuous basis should not exceed 1/7 of the rated capacity of cylinder. (In other words, withdrawal rate from a 300 cu. ft. cylinder should not be greater than 43 cfh.) Withdrawal rates will differ with other fuel gases. Lack of fuel gas flow can overheat the tip or nozzle and cause a flashback."http://www.esabna.com/EUWeb/OXY_handbook/589oxy1_21.htm
Reply:Thanks fellas.I like solid reference material.If you fight long enough, you will win. The problem is it costs too damned much.- Lee Cheng
Reply:To bellflower, the 1/7 withdrawal rate is very important.  References are found in O/A torch manufacturer manuals such as Smith and Victor.  At least all the ones I've read.  Also OSHA regulations which used to say 1/7 but have gone to 1/10 I think.  My guess is it provides a safety margin and is easier math.Also note that welding tips have a RANGE of withdrawal rates.  Smith's manual states that their published cfm rates for welding tips are for when the acetylene flame is adjusted just to where it isn't smoking.  But you can adjust it higher.  So be careful with using a tip that is rated right at the limit of your cylinder capacity.
Reply:Do what I did, go to propane and forget about withdrawal rules. You don't have those problems with LP. It's cheaper, more readily available, and actually put out more BTU's than acetylene."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Originally Posted by Stick-manDo what I did, go to propane and forget about withdrawal rules. You don't have those problems with LP. It's cheaper, more readily available, and actually put out more BTU's than acetylene.
Reply:Originally Posted by Stick-manDo what I did, go to propane and forget about withdrawal rules. You don't have those problems with LP. It's cheaper, more readily available, and actually put out more BTU's than acetylene.
Reply:Try thesehttp://weldingweb.com/vbb/showthread.php?t=40290http://www.cousesteel.com/AndysPlace...Acetylene.html"Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Latest edition of the CGA standard says 1/10 for intermittent use, 1/15 for continuousExperience is something you get right after you need it
Reply:Originally Posted by bellflowerI'm not being snarky at all asking this:Those handheld propane torches run way cooler than MAPP, and MAPP is not capable of anything anywhere near what a Prestolite Turbotorch is, which is nowhere near as hot as a traditional O/A rig..I know this is apples and oranges when comparing throwaway Bernz and MAPP to Prestolite Turbotorch tanks to fullsize O/A rigs, but the properties of the gas and the linear progression of their heat outputs and welding capabilities makes me ask the question.. Like I said, I'm not trying to catch you in a lie, I just know what I know, and from this angle is doesn't add up.Let me know. If there were a cheaper alternative with fewer stability concerns, I'd be on it like Oprah on a cookie someone dropped on the floor.
Reply:I appreciate all the replies, and thank you Stick Man.I'll read up on that stuff and check it out.If you fight long enough, you will win. The problem is it costs too damned much.- Lee Cheng