Plugged in the plasma tonight for the first time. Plumbed in the air, plugged her in, turned her on, lots of sparks, lots of whoosh but no cutting??

I was trying to cut some 16g sheet, it was marking the surface and did blow a small hole but I had to hold it in the same place for around 8-10 seconds.

Enough air pressure??

Was the ground (earth) connected OK?
That can make a big difference.

Alan

unplug the plasma and check the flow of air when you pull the trigger. Should be a good gust. Dont think that will be the problem though, id expect a warning light if there wasnt enough air.

Have you checked the polarity ?

Ie work piece pos torch neg on mine.

Try cutting from the edge of the sheet, if you hold it down on the flat it might be gobbing your nozzle.

It doesn't flow when the unit is switched off it must have a electrical control valve. When it on though you can feel the jet reaction when you press the button.

I'm pretty sure the ground was good its a brand new good quality clamp and it was right next to the attempted cut on clean metal. I will check again tomorrow though.

Could the polarity be wrong???? There is only one way to hook up the cables.

[Edited on 24/11/09 by liam.mccaffrey]

Has it got a built in regulator for the air pressure ? Is it set correctly? Have you got a decent air supply? Is the nozzle in good condition? Have you got any instructions? If so have you read them? As you ask enough air pressure ? Their good when they work

in fear of sucking eggs and old dogs jumping to mind,if its a scratch torch were you holding it to the job,not hovering above as you would with a burning torch?

its a hf start and i tried both I will check all the connections and the air supply pressure tomorrow

The tip inside the torch is shot unscrew the ceramic bit and then you will see a bit like

----||---- if it looks like ----||- then it is knackerd

ill check but its a brand new tip, torch and machine

could be that the inner eletrode in the torch is sticking
most of the smaller or older sets have a type where it is lifted off a seat by air pressure starting up striking your start arc.
take off your nozzle and try to push it in/out
a small bit of dust/grit make them stick

to much air maybe or a shot nozle,eletrode if not

if your set has mesh cut its hf and is not like this
trust me i used to sell plasmas tigs and welding supplys

sounds like dodgy ground to me

i.e. to the work piece

sounds exactly like what i get when i forget to conect the ground clip

but its brand new just take it back and ask them to check it out

aitch

sounds like not enough air....if you havnt got a bolt of plasma then the current isnt super heating the air...my plasma set says to run at 4.4bar, but i find it wont cut at that and i have to run at 6bar....also you may have a purge button on there, press that before firing it....