Urban Gardini
Change the PTFE seal on the nozzle.

Yves 作者
Ok Urban, thanks for the advice, I 'll try that.
That said, my nozzles (0.2 as the 0.4mm one) are very recent : they have been of little use only.

Urban Gardini
No problem mate! That's odd though as I've never had any issues with air leaks on my two H&S over the years. If the leaks continue I'd try to put an o-ring behind the threads on the body.

Yves 作者
Hello Urban,
That's a good idea.
I've also tried to put some little airbrush grease (Tamiya or Mr Hobby) or vaseline on the thread, because I often do so with others airbrushes use, to improve proof sealing (and avoid overtightening) : it seems to be good, not absolutly necessary but...

Urban Gardini
Sorry to say it but the grease don't help with leaks. Use bees wax instead on the threads as that's a great sealant to use. As for vaseline you should stop using it as it's petroleum based and as such not suitable to use together with paints.