O/A cutting problem with metal welding behind torch

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i am using a victor O/A setup to cut some 1/4" steel plate.  My O2 is at 25 and my Acetylene is at 3.  I have cleaned the tip really well but when I cut the metal welds back behind the torch.  I have varied the speed at which I cut, distance from the torch tip to the plate and nothing seems to work othere than to move the torch a little bit side to side as I cut.  Any advice would be much appreciated.
Reply:I usually run a little more acetylene. You are angling the cutting head back so the metal is preheated as you advance the cut?
Reply:you should be running atleast 5 on the fuel...not much more for most situations...5 is goodCHRIS
Reply:I have the head of the torch 90 degrees to the piece of metal I am cutting.  Should I angle the head back some?  45 degrees maybe?
Reply:don't be afraid to use my feul or oxy..i allways piont the torch just a "c" hair front wards i find that helps a bite aswell !!thanxs,bcwelder
Reply:the instructions I was given as a young welder was that for thin stuff, point the tip forward, like 45 degrees is good.   For thicker stuff the torch should be 90 degrees.  I find that it just varies from the size of the tip.  Try it differnt ways.  Then another thing, you might need to let the cut heat up a tad longer before starting the cut.  You may not be heating the metal up deep enough before adding the oxy jet.  Another thing is dont hold your torch too close to the plate.  It should be close, but 1/8" is good, can be even a little higher than that.  Good luck
Reply:excellent feedback.  i will skip mowing the lawn so I can try it out.  Thanks
Reply:I agree with everything posted so far but would like to add that setting the flame is important. Lite the torch and then  set to a natural flame so that  the blue cones have sharp points then hold the ocy lever down and readjust the oxy until blue cones are as sharp as possible. open the ocy.valve just far enough to get a sharp point no farther.
Reply:digr,  excellent and necessary sugg.   Its funny I am soo well versed with this stuff sometimes I remember good points, and miss even gooder points lol.   Good luckCHRIs
Reply:My cutting torch has a knob that is up towards the torch head.  it is separate from the Oxy and Acety knobs.  is this what I should be fine tuning the oxy cones with as I am pressing down on the cutting lever?
Reply:ranger,You can open the oxy valve closest to the hose all the way and use the closest to the torch head to "tune" the flameLet's try it this way!!!! No, Really, It'll work...maybe.
Reply:Rgr  that,  but a quick reminder, when you arent using the torch shut the lower valve off.  The upper valve doesnt shut off the oxy cut lever.  Therefore if the torch inadvertently lays on the cut lever it will make your beautiful magnificant and rather expensive O2 go bye bye.  Good luckCHRIS
Reply:Ranger,What size of tip? Sounds like maybe just a little too big a tip to me. Guys who cut a lot can get by with just about any set-up. I can't do that quite so well. I need to set up pretty close to reccommended parameters to get something even close to a cut instead of a hatchet job.  Hard for me to concieve but you really need to run quite a lot smaller tip than you think sometimes. One problem is most of us can't afford a basket full of cutting tips so quite often we are caught using one well above and below reccommended ranges.Cutting 1/4 inch you should be using a -00- or a -0- tip if possible.
Reply:the tip is a 00 i believe.  at least it has a 00 in the label.
Reply:sandys right.  Of course I cant really comment about tip sizes.   Im the guy hes referring to who uses any set up and can make a decent cut.  The trick to using any ole tip is matching your head angle and your cut speed.  Always start out with a 90 deg to the plate.  You want to heat up to a glow, and depending on how thick, something you need a little bit, or a lot more than that.  If its the right size tip wont take long, few seconds with a properly lit torch.  Shop I used to work for we did a lot of 1/4" structural stock.   3/16" wall thickness for our tanks and silos, 1/2" and 3/4" for certain pads and feet for the structures, and also for some other reasons like abrasion protection.   With all these differnt thicknesses, we had one torch size.  It was matched for the 1/4" angles.  Everything else just had to be adjusted accordingly.  I could cut a 3/4" plate almost as clean and most of the guys in there with their 1/4" steels.  ONce you get your cut started you need to maintain a faster speed on the thin, and a slower on the thick.  Its all about watching the cut progress though.  With a little time and practice youll get the hang of it and will be dropping them pieces off with minimal grinding in no timeGOOD LUCKCHRIS