Airbrush blowing but not spraying: Help needed please

[lawnor 25939xp 0]

I’ve had my H&S Ultra for years.  I clean it regularly and take good care of it.  I’ve been using it this morning.  I gave it a good clean out before changing paints and on a whim I did a test spray with water before adding paint and now nothing sprays out. Troubleshooting says to remove the nut at the back and slide the needle back and forth by hand while spraying.  Still nothing happens.  If I remove the needle and spray nothing passes through the nozzle but air.  I can get water to pass through the nozzleif I suck on the nozzle with the needle out while spraying (No idea why I thought to do that.  I’m not in the habbit of sucking my airbrush)

I’ve spent the last few hours cleaning and re-cleaning the whole thing and still nothing.  I have a spare needle and nozzle set I’ve tested and the problem persists so they’re not the issue.  I thought to check the seal in the main body.  Removing that part liberated a ring of dirt which I thought might be a decayed seal, but I’ve watched a video on replacing seals on a different H&S airbrush and it only has a white seal there and mine looks fine to me.

The whole thing has been stripped, cleaned, rebuilt and tested dozens of times.  I’m out of ideas.  I’d love to put it through an ultrasonic bath but mine blew up in the heat this week (Recomendations for a reliable replacement appreciated.  £30 ebay/amazon generics lasted me 18 months first time, then its about 6 months after that).  Can anyone please help?  All suggestions appreciated.

[warzanKeymaster 31125xp 1]

OK list of suggestions (some may be stupid!)

1) Is compressor turned on

2) Is air actually coming out of the compressor

3) Have you adjusted the PSI or anything

4) Have you tried backflushing with airbrush cleaner (holding your finger over the nozzle)

[lawnor 25939xp 0]

@warzan Nothing wrong with stupid.  I’m hoping its something stupid.  Wouldn’t be the first time I’ve missed something obvious or dumb

1) Yes.  I’ve been using it all day

2) Yes.  See above.  Also air still passes through the nozzle

3) I touched nothing.  I sprayed green camo on my tank, took the airbutsh apart for a quick clean while waiting for paint to dry.  When I put it back together it would blow but not even water would pass through it.  I did not touch the compressor or the PSI.

4) I have tried backflushing many times.  Its my go to whenever I think there might be a blockage.  I’ve backflushed with water, with soapy water and with airbrush cleaner.  No change.

[tankkommanderParticipant 6423xp 2]

[lawnor 25939xp 0]

@tankkommander thanks, but thats the first thing I did.

[jemmyParticipant 2428xp 2]

Dear Lawnor,

some time ago I had the same problem. The reason was found at the back part of the airbrush itself. Me and a friend opened the back of the airbrush and realized the needle wasnt going  back and forth, when pressing the handle. Thus no colour or water could get out of the colour pot into the air stream. The outlet just didn´t open. I had to order a spare part and all was good again. (Point was I accidently let the thing fall down on the floor.)

In my language the spare part to be replaced is called Nadelspannfutter. Try as I may I could not find a translation for this. It looks like a screw and and you fix the needle to it with the help of a nut.

Try this: Unscrew the front part of your airbrush so that you can see the tip of the needle. Then operate the handle. If the needle does not move back and forth, you are likely to have found the reason for your problem. Best thing would be to consult the manual of the airbrush to identify the name of the part properly.

My friend told me, the Nadelspannfutter is a part that breaks easily if the airbrush falls down on to a hard underground. And when fixing the needle with the nut I should always be gentle and careful, as this is one of the most delicate parts of an aisbrush.

Good luck and success with your airbrush.

[lawnor 25939xp 0]

@jemmy  I see that word in the manual.  Translates to “Needle Chuck”, Part F.

My needle moves fine.  Good thinking, but not my issue apparently.

I’ve been advised to lube the needle and the o rings.  I’ve lubed all I can access with no improvement.  I’ve also tweaked the screw inside the air inlet valve so its as tight as it can be while still allowing full motion of the lever.

[horati0nosebl0wer 19647xp 2]

Eek! H&S are definitely top of the line and quite precisely built. I’ve been plugging along with my Badgers (Patriot 105 and Sotar 2020) and I’ve been forgiven for my past mistakes in learning. Here’s a video that has been good for me that could be useful to you. The video features some Iwata but the precision of the machining hits the mark of my Sotar and about the same as the insides of a H&S as far as I’ve seen.

Definitely get paper points instead of going about anything with mini wire brushes

[lawnor 25939xp 1]

https://drive.google.com/file/d/1CFCHIAUWwe6vMwRtWy_trRf0r77Wmxcj/view?usp=sharing

Video of my airbrush doing nothing, as requested on discord for diagnosis purposes.

[lawnor 25939xp 1]

It seems more than doubling the pressure was enough to get water to spray so presumably there was a blockage somewhere.  Spraying water, backflushing, spraying cleaning fluid, backflushing and then reducing PSI back down again has yielded results!  I can stop pricing up a replacement now thank god.  Gonna do one more clean, but thank you to everyone here and on discords who tried to help.  I might have given up sooner without you.

[gilbert 122xp 1]

Was just cogitatin-ing on your airbrush woes whilst doing some hobbytime and glad to come back to see you sorted.

From your vid and description of sorting through pressure I wonder if you own a reamer?

 

[lawnor 25939xp 0]

I spoke too soon.  The probelm is not fixed.  When I get the pressure to normal layers I get minial spray at best.  Im still cleaning and blasting at higher pressure but its not working properly.

[lawnor 25939xp 0]

@gilbert I didn’t know it was called that, but yes I do.  Comes as part of the H&S airbrush cleaning kit.  Im careful where I use it as it can damage parts.  its good for cleaning inside the nozzle though.  Nozzle, nozzle cap and needle are not the problems though as I have replaced them all and the problem persists.

[gilbert 122xp 1]

@lawnor If it possibly a air leak somewhere then. How much are you breaking it down at this point? Might be time to take it to bits? (It will go back together, you just gotta remember how)

I’m thinking your needle packing is failing or there’s a rubber o-ring that is failing. Possibly somethings not tight enough too.  Have you put a dab of water around sealing surfaces at the nozzle end to check for bubbles?

[lawnor 25939xp 2]

I started taking it to bits 6-7 hours ago 🙂

Problem solved now, thank god.  Since I last posted I took it apart and cleaned it, cranked up the pressure and blasted it througn twice with no success.  On the third attempt I removed the seal in the middle of the main body again and a large (relatively speaking) lump of gunk fell out that wasn’t there earlier today when I took it out then.  After a rebuild I tested it and it felt right.  Spraying a little primer on to some card I think im getting better spray than I have in a long time.  I guess whatever is wrong has been building up for a while.  I’ve since varnished some stuff and cleaned up for the day.

Its taken most of the day but I am confident this problem is now solved and I have a working airbrush once more.  I’m keen to actually apply paint with it again and see how that feels.

I’m still interested in Ultrasonic bath recommendations and links if anyone has any.

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