Heavy Duty vs Medium Duty Oxy Acetylene cutting

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I am new to the forum and have a couple of questions.  I recently acquired a 200 cf oxygen  cylinder paired with a 115 cf acetylene cylinder.  I want to get the most bang for my buck as far as being able to cut metal quickly and effectively.  I have noticed some regulators are categorized as "medium-duty" and some are "heavy-duty".    I figure that there wouldn't be much point in buying a "heavy-duty" regulator set if my torch is not of the same rating.  My main question is this:  Is there a noticeable difference between medium vs heavy when it comes to cutting steel?  Is there a rate of flow or something that I should be looking for when purchasing regulators, hoses, and torches?  Thanks.
Reply:Having a heavy duty reg shouldn't affect your torch and going with a reg with a higher flow rating shouldnt affect it either, as long as you can dial it down to the flow/pressure you need for the torch your using. Having too low of flow through your reg will cause you no end of issues and will make nothing work right.
Reply:With a 115 CF acet cylinder, "medium duty" torch/regs should be fine.  You can only draw off so much acetylene safely."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:I have a mental image in my head (from years ago) when having automotive exhaust replaced in a dedicated muffler shop.  Less than one minute after confirming my choice of exhaust system I hear the clang clang from the bay where my old exhaust has hit the floor of the shop.  I think it took them longer to raise my truck on the lift than it did to cut the hangers and bolts with their cutting torch.  They didn't even bother trying to put a wrench on it.  One thing that I did notice at the time that I thought was odd was when the mechanic was firing up the torch the acetylene was burning in a flame that had to be 6 to 8 feet long before he turned on the oxygen.  That is the only time I have ever seen a torch pushing out that much acetylene.   So far I have not been able to cut anything nearly that fast.
Reply:When you're speaking oxy-acetylene Heavy duty means HEAVY DUTY Unless you're playing with skyscrapers, giant equipment for mining or building ships; medium pretty much means"for everything".Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:Originally Posted by BurpeeWhen you're speaking oxy-acetylene Heavy duty means HEAVY DUTY Unless you're playing with skyscrapers, giant equipment for mining or building ships; medium pretty much means"for everything".
Reply:Unless your cutting 2" or thicker material, you really don't need a "big" torch
Reply:Based on your tank size and the 1/7 rule, you shouldn't be cutting more that about 1" - 1.5" anyway."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:I run big two stage Linde/Oxweld regulators on my regular o/a setup.  I use large dedicated Oxweld or Victor cutting torches when required.  I use a smaller medium duty Purox combination torch for most of my work.  I find the torch is more easily manipulated in tight places and the smaller torch/tips save some gas."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:I have an older Craftsman torch with the cutting head only.  I am not sure what type of "welding" connection I need to be looking for.  Since the cutting tip is a "Harris" I assume that the handle portion, even though it is "Craftsman", would be in the "Harris" family.  How do I know which mixer to order?  The cutting torch works fine.  I don't want to order a whole other kit just to be able to do some light welding / brazing.  Alt Welding Supply has several styles of "mixers" to fit "Harris" torch handles.  I've already bought new regulators and hoses so I don't need a "kit".   Any advice?Here is a picture of my Craftsman torch:Last edited by DIY GUY; 11-05-2013 at 01:47 PM.
Reply:After looking at the price of the "mixer" (between $25 and $50) I might as well go ahead and buy a whole new torch with welding tips included.  damn it.
Reply:"Medium Duty" is more than adiquate for any home/shop/farm.I've got a 50+ year old set that my dad bought. It runs on bottles that are small enought to carry into and out of the welding shop.I used that setup to cut up a dump truck frame and turn it into a road grader.Like what was mentioned before, just be careful of how fast you draw off the acetylene and you'll be fine.Then we can talk about getting into *REAL* arc welding. Be wary of The Numbers: Figures don't lie,. but liars can figure.Welders:2008 Lincoln 140 GMAW&FCAW2012 HF 165 'toy' GTAW&SMAW1970's Cobbled together O/A
Reply:Okay... I am getting closer to understanding these connections.  After removing my cutting head and looking at the connection it appears to be the same as Harris.  I don't know if it is E43 or D85.  So far that looks like the two possibilities.  Anybody familiar with the Harris welding tips know the difference between E43 and D85 ???  Thanks.
Reply:Like with most things, there is a lot to get your arms around. Harris makes about 6 mixers for the 43 and 85 torches.  There are positive pressure mixers and low pressure mixers.  There are mixers for a couple of specifc tips, and there are mixers for specific gases.It looks like your torch is similar to a 85, but not exactly.  85 makes a bit of sense, as it is the lighter duty of the 2 torches.Since you have acetylene, this would put you on a D85 mixer and the 23A90 tipsYou might be able to sneak a J-63-1 rosebud on there, but barelyExperience is something you get right after you need it
Reply:So I found this website:  http://www.searspartsdirect.com/ where they appear to have "some" parts still available for my torch.After cleaning up the torch and under a magnifying glass I was able to read the model number for my Craftsman torch.Model #31354408  the website calls this model a "two-stage welding outfit".  It lists the part numbers but no cross reference to other manufacturers attachments.  Sears Parts Direct shows the mixer part #9101086 or #9101064I imagine that I will be able to use some aftermarket fittings as soon as I learn what fits.  The only item that I would like to have that isn't available is their "owners manual"  # 9504070 I read on one forum "possibly this one" that there may be a manual that covers more than one torch model.  It won't make or break me if I don't find one but I could get lucky and find someone who has made a pdf copy.  I will be all stocked up here shortly anyway.  I ordered 5 pounds of brazing rods, flux, and a Harris Steelworker torch kit.  Combined with what I already have that should keep me going for a while.