Cutting torch adjustment

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I just purchased a Victor Super Range II cutting torch outfit.  I am using Oxygen and Chemolene (propane with additives to make it as hot as acetylene).  I am cutting 1/4 and 3/8 material, and it takes at least 60 seconds to preheat to the point where the torch will cut, but then it cuts quickly and fine.  I am using propane tips, 3lbs. Oxygen, and 35lbs. on the fuel.  What is the correct flame adjustment?  I feel that I maight not be adjusting properly to minimize the heat up time.  Any help would be appreciated.
Reply:your cutting with only 3lbs of oxy? you need more like 60 to cut withChuckASME Pressure Vessel welder
Reply:with ox and acetalyne for 1/4-3/8 5psi fuel, 40 psi ox
Reply:I was cutting 5/8 " today with 30 lbs. ox
Reply:Are you sure you did not flip the numbers, perhaps 35 oxygen and 3 fuel.  Is your 02 adjustable at the torch head and on the body?  If so, then you need to open the body valve up all the way and make flame adjustments at the head.  Does sound like a long preheat, though I have never used chemolene. I have used propane and it does not take that long for that metal. I use the following technique when trying to adjust pressure for different welding tips.You could experiment to find the correct fuel pressure.  With only the fuel torch valve open (wide open), ignite the flame.  Adjust the tank pressure until the flame is not connected to the torch tip, this is the max capacity of the torch tip., bring the flame just back to the torch by adjusting the torch valve.  You can do the same thing with the O2 by wide opening the torch valves and adjusting the tank pressure to get a neutral flame.  You will need more O2 for the cutting action.  You don't need to do each time you set up your torch but it will give you some idea of the tip capacity.
Reply:Oh Yea,Where are you starting your cut?  On an edge or in the middle of a piece of metal.  In the middle would take a bit longer to preheat.  I know it would take longer with propane.  Also how close are you holding the torch to the metal, for max heat the preheat cones should just touch the metal.  Do you have the right type tip/ right size?  Propane takes a two piece tip unlike acetylene. You may know all of this, just making suggestions.  Hope it helps.
Reply:With a fuel gas tip you can expect it to take a bit longer to heat the metal.  You are only cutting thin material.  25 psi oxy should be about right and 5 on the fuel.  Keep in mind that fuel gas neutral flames are not exactly like acetylene.  If anything go a bit lean with too much oxy on your pereheat cones.  That way you get a slightly hotter flame.  You will find that with fuel gas tips your height is not so sensitive.  Once you establish your cut you can carry it when the tip is half an inch off the surface.You adjust to a neutral with you oxy trigger pressed.  Remove the feather then a little more oxy.  The preheat flame should be a bit noisy unlike oxy-acetylene.
Reply:Tapwelder -You are correct, I did flip the numbers (typo on my part)... I am using 35 oxygen and 3 fuel.  I guess I don't have a good understanding of the concept of a "nuetral" flame.  I am using a 2 piece fuel tip of the correct size, with 3lbs. fuel and 35 lbs. oxygen.  I am opening the fuel valve and lighting the torch... and then using the O2 valve at the head to adjust the flame (torch body O2 valve is left full open).  The cone flame on the propane tips seems to be much shorter than with acetylene... only about 1/8" off the tip... am I using too much O2?  If I cut back on the O2 the cone lengthens, but it doesn't seem as well defined as it should be.I will play with the pressures some.  In the meantime, if anyone can guide me throught the correct way to get the hotest nuetral flame, I would appreciat it.
Reply:As Lotech suggested you may end up using a lean (oxidizing flame)  It is a noisey flame.   Your number don't appear to far off. I find a nuetral flame by looking at the inner cones first.  With a reducing or carburizing (fuel rich) flame the cones are rounded and the flame is fluttery.  Continuing to add oxygen will change the cones to sharper shape, but not pin sharp the color will be close to the rich cone color( this is neutral).  The flame will not be fluttery but will fan outward.  The Oxidizing ( fuel lean) flame will have pin sharp light more whitish cones.  The flame will be be narrow and pointed at the end.  Lean is a loud hissing flame.You probably want more O2.  More 02 more heat.  Also as Lotech suggested pull back after cutting has started in order to prevent melting the metal. Great explanation Lotech.