need plasma cutter help

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i'm trying to get an old HF plasma cutter going.  i bought it without an electrode and found out that the one it needs is no longer made so i had to buy a new replacement torch so i can get consumables.  the cutter is a 16/30 amp output and the torch i bought is almost identical but it is rated at 50 amp.  i'm not able to get the torch to start.  the torch is wired positive to cap and negative to electrode and i read 274VDC between them when i pull the trigger but no flame, just air.  i've tried it touching the work and not touching the work.  could a 50amp torch maybe have a bigger gap between the electrode and cap and keep it from starting?  i measure the gap at .058".  any help will be greatly apreciated, thanks
Reply:And the brand and model of the machine is? Pictures may help. There are hundreds of different possibilities of high frequency start plasma cutters....they are not all the same!Jim
Reply:HF could also be "Harbor Freight". That said, I dunno...The soldering toys pay for the welding toys.Hakko 928 dual iron, 4xHakko 936Madell 850D Hot Air SMT ReworkMiller 252, HTP Invertig 201 AC/DC, and a Hypertherm 45.
Reply:sorry bout that, all the identifying labels are gone.  the closes thing i've found to it is a chicago electric model 45949 sold by harbor freight.  the torch it came with was a Cabaro and i bought a 50amp Cabaro.  the original torch had a cap that moved back toward the electrode when you triggered it, the replacement i bought has a fixed cap and electrode.  i may have bought the wrong torch head.  the picture is of the torch that came with the machine. Attached Images
Reply:This was an Italian unit.  The torch you have can be replaced with a trafimet. PM me.  I might be able to help you. Or, HTP has new torches for this unit, or one that should fit anyway.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:thanks lugweld, i was hopeing to get it going with what i've got. i'm not sure it's worth buying another new torch.
Reply:HF ignition doesn't necessarily mean that your machine has to have a pilot arc. And the HF may only work at distances as small as .02" between tip and workpiece. My Cebora has the pilot arc, the Esab on the other hand works fine without one.Did you actually try to start an arc against some scrap metal?
Reply:i did chevyman. i've confused things, when i said hf, i ment harbor freight.  from looking at the circuitry,  i don't think it has high freq start.  i not sure how the original torch worked, the electrode is stationary and the cap moves back to it when you trigger.  i've read about torches that the electrode and cap are touching before you trigger,  that gives you a spark when you trigger and then the air moves them apart.  i'll read up on the Esab.  thanks
Reply:one more thing, i think it originally was designed for a pilot arc.   the unit has two 50amp contactors, right now when i trigger the torch, one contactor closes and puts 274VDC across the electrode and the cap and the air flow starts.  the other contactor which, when closed, puts positive voltage to the work clamp.  i'm  thinking that when i get a pilot arc, it will cause the second contactor to close.  as it is now,  this contactor is not closing and the work clamp is not part of the circuit.