First time I heard someone talking about post-flow on a plasma cutter, I had no bloody idea what they were on about.
I remember thinking:
“Why the hell would I want air coming out of the torch after I’ve finished cutting?”
“That’s just going to piss air away.”
And when you’re running a small compressor in a cold Kiwi shed, air isn’t exactly unlimited.
So I did what most of us do.
Ignored it.
Then one day I actually played with the setting.
And pretty quickly, the penny bloody dropped.
Post-flow isn’t there to waste air.
It’s there to stop you cooking your torch and consumables to death after the cut.
Once I figured that out, it stopped being some pointless knob and became one of the most important bloody settings on the machine.
What Post-Flow Actually Is (No Bullsh*t)
Post-flow is how long air keeps flowing after you let go of the trigger.
Arc stops.
Power stops.
Air keeps pissing out.
That airflow:
● Cools the tip
● Cools the electrode
● Blows hot crap out of the nozzle
● Stops heat soaking into the torch
That’s it.
Most adjustable machines give you about 1 to 10 seconds.
You don’t need it maxed out.
But zero post-flow is just asking for trouble.
Why Your Tips Get F*cked Without It
When you finish a cut, your consumables are red hot.
If the air shuts off straight away, all that heat just sits there.
Cooking.
Heat kills:
● Tips
● Electrodes
● Swirl rings
Cook them often enough and they’re scrap.
Post-flow gives that heat somewhere to go.
Cooler parts = longer life.
Dead simple.
My “You’re a Dumbass” Moment
I had mine set almost to zero.
Consumables lasted… average.
One day I bumped it up a couple of seconds.
That’s it.
Nothing else changed.
Next thing I noticed:
● Tips lasted longer
● Arc felt smoother
● Less random sputtering
Same machine. Same steel.
Same pressure.
Only difference was post-flow.
That’s when I realised I’d been the problem.
Rough Post-Flow Settings That Actually Work
Most machines live around:
1–10 seconds
Start here:
● Light work: 1–2 seconds
● General cutting: 2–5 seconds
● Thick steel or long cuts: 4–8 seconds
You’re aiming for:
Enough air to cool the torch.
Not so much that your little 2hp compressor starts having a nervous breakdown.
If You Pierce a Lot, You Really Need It
Piercing dumps a massive amount of heat straight into the tip.
If you don’t pull that heat back out afterward, you’re murdering consumables.
Post-flow does that job.
Simple.
Signs Your Post-Flow Is Too Low
● Tips turn blue fast
● Consumables die early
● Torch stays bloody hot
● Arc gets unstable Signs it’s too high:
● Air tank empties fast
● Compressor never shuts up
Find the middle ground.
Post-Flow Won’t Save Sh*t Air
If your air is wet, oily, dirty, or pressure is wrong…
Post-flow won’t magically fix it.
You still need:
● Dry air
● Correct pressure
● Not running max amps all day
Post-flow just stops you cooking parts after the cut.
It’s one piece of the puzzle.
NZ Reality Check
Consumables in NZ aren’t cheap once you add shipping and waiting time.
Burning through tips faster than you should hurts.
If you’re running common torches like AG-60 or PT-31, correct cooling alone can double consumable life.
We stock and ship plasma consumables from New Zealand, so replacements are easy to get.
But the real goal is not needing replacements every five minutes in the first place.
Post-flow helps do that.
Final Answer (Straight Up)
Post-flow is how long air keeps flowing after you stop cutting.
It cools the torch.
It protects consumables. It saves you money.
Most machines run somewhere between 1 and 10 seconds.
You only need enough to cool things properly.
Set it.
Use it.
Stop cooking your tips.