No paint is coming through my airbrush

[Guest]

Ok chaps,

Last night I stripped it and re-assembled my airbrush so when it came to cleaning I wouldnt be faffing around. This morning I fixed the airbrush onto the compresser. Ok got air when I pushed for air, all ok so far. Mixed the arcylic paint with thinner until I had a milky solution, so thought time to put it in the hopper.

So with eager I pressed for air then pulled back for paint...... No paint... wtf! How could this be! Air but no paint!

So I have a few thoughts why this may be.... Could the needle be far too forward in the nozzle which would prevent paint from flowing? At the rear of the airbrush there is something turns that may adjust something? I notice if it is tight down, I cant moev the trigger back, if its loosened then the trigger will move back. Either way, still no paint coming through. I tried different pressure also.

Any ideas? The airbrush I got was discussed in a previous thread. It does the job but for some reason Its not playing the game with me.

Airbrush Compressor Kit I - Airbrush Compressors | Airbrushes | Compressors

[Guest]

The adjuster you mention adjusts the position of the needle and therefore the amount of paint that flows when you depress the trigger. If you back that right off and you still get no paint then you might have a blockage in the suction tube.

If it worked OK before you cleaned it though it looks more like you need to set the needle position. You usually find a lock ring then some form of adjusting the needle position. Undo the lockring, adjust the needle and then relock the lock ring.

I would play around with just thinners or even water in the brush while you get it set up correctly.

[PJP]

There is a knurled ring which clamps the needle, at the back end of the needle.

Slacken that off until the needle will move within in. Then push the needle GENTLY forward until it will go no further and reclamp the ring around the needle.

Operate the paint button to see if the needle slides back and forth with the button operation.

If it does, the needle will be operating like the valve it effectively is.

If it doesn't slide to and fro the needle isn't clamped or the operation button isn't moving the needle.

What you do then is to inspect the operating button to see if it actually bears on the needle locking asembly at the bottm of the button. If not dismantle and re assemble with care so that the mechanism slides the needle to and fro.

If the needle slides when you call for paint, with no paaint released, you have a blockage.

Use water for test purposes as Richard suggests.

Let us know if this works.

P

[Guest]

Ok will try on my lunch break and let you know. So the theory is, that pushing back on the trigger, moves the needle back which allows the paint to flow? There shouldnt be a blockage as this thing is new. If it still doesnt work, Ill post up some pics of the set up I have.

Thanks

[stona]

When you depress the trigger (don't pull it back) are you getting air through the nozzle. You need to feel for this,spray it onto your tongue. This will check that your air is getting to the right place,it may sound the same if it is escaping somewhere else!

If this is okay then set the needle and try to spray water as PJP suggests.

Press for air and then pull back for your water.

If nothing comes through then there is a blockage somewhere in the paint track.

I'm not familiar with your brush,I don't know what kind of feed it has,but you need to clean any tubes or tracks that the paint should flow along. Interdental brushes soaked in cellulose thinners are the best thing I know for doing this.

Let us know how you get on.

Cheers

Steve

[Guest]

Ok, I have partly assembled the air brush. So far I have out the needle back in and the nozzle needle. The tightening ring at the back I have tightened up and when I press the trigger back, the needle moves back and forward. So this is the correct mechanical operation and what I should expect so far?

If you look closely, at rest the needle is protruding just out of the nozzle ring holder (if thats the correct name)

Pic attached.

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[Guest]

Assembled it all together and put water through it.... Eureka! I've got a nice fine spray coming through D Seems like it must have been the needle position that was incorrect or the needle wasnt locked down into the trigger mechanism. Thanks for you help guys. In hindsight I should have used water first to make sure it would spray. But hey, learn something new every day. Anyway, I can now go and spray this tank thats been sitting on my desk all morning staring at me!

Cheers

[stona]

Glad you're sorted. 99 times out of 100 when an airbrush doesn't work properly it's something fairly simple.

When I store my airbrushes I always pull the needle back a bit so that it isn't sitting in the nozzle. Do I remember to lock it forward again before I spray? Not every time!!!

Cheers

Steve

[Guest]

I am really pleased with the finish an airbrush provides compared to normal brushing on large surfaces. Really smooth and the details is far crisper. My friend bought the same air brush, Ive passed my starter tips on provided by yourselves. Also, I didnt realise that when you dont press for air, the compressor turns itself off. At first I thought... 'not again' but realised when it reaches peak pressure in the chamber it knocks the power off. It only starts up again when you press for air.

Cheers

Rob

[Guest]

Rob

Next time you strip it down to clean, count the number of turns on the locking screw/needle adjusting screw then when you put it back togther make sure that you use the same amount of turns, that way you should be where you were before cleaning. Also, if you are using acrylics and a top feed airbrush, once you have run the cleaning fluid through, it is always advisable to put some cleaning fluid in the feed chamber and leave the airbrush in the holder. That way any small bits of paint that were not cleared will clear away in the fluid. Just need to make sure that it is empty and dried out before you add more paint or you will get a marbling effect when you spray paint onto the surface of the model. I normally will run a small amount of paint through onto a cloth before it goes anywhere near the model. I usually find that works.

Andy

[Guest]

For a thorough clean after a spray session see my video here:

You don't need any specialist equipment.

It's good you're now sorted, I can tell you that the problem was some sort of blockage, the frst mistake made was to assume that as you're getting air through paint should follow, what actually happens in all needle fed brushes, is that the air flows through the nozzle cap on the outside of the nozzle, not through the paint cup and feed tube to push the paint out, this creates a pressure differential which in turn draws paint from the cup through the nozzle, so air + no paint = blockage in paint feed tube to nozzle or nozzle itself, (most likely), sometimes, especially with acrylic, you can get it drying in the nozzle and blocking, sometimes you can clear it mid spray if this occurs by backflushing

The air pressure operation is the same principal as the venturi in a carburettor or an aircraft wing shape generating lift through pressure differential.

Hope this makes sense, it's well worth finding out how something works as this can give you a better insight into what may be causing a non operational problem.

I'll see about making a video explaining the operation of an airbrush if anyones interested?

[Guest]

I have just bought an old badger 150-1 anthem airbrush a sprayed water through it and had a go with very thinned paint and cleaned it thoroughly afterwards (I think! needle nozzle etc) I tried to spray some cleaner through it afterwards, but no cleaner/liquid came out only air? is this the same issue as described hear? the air stream seemed strong as I put the PSi up to 30 but no liquid? hope it isn't broke, I've tried back spraying and sonic cleaning but nothing I'm stumped? any advice would be greatly appreciated, as I feel like I am jinxed when it comes too airbrushing having had the two cheap brushes that came with the compressor fall to pieces when stripping down for cleaning spring flew out lost forever and some other disaster I want to keep my chin up and continue but its getting frustrating! please can a experienced airbrusher help?

[Guest]

sorry about spelling mistakes grammer etc, must be down to frustration!