Airbrush Problem

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The air valve (trigger valve) can be disassembled and cleaned. Use a cellulose (lacquer) thinner. Use a very sparing amount of airbrush lubricant when reassembling. (You can also use lip balm around the threads as a sealant.) The parts diagram shows how the thing comes apart. The threads are very fine, and the knurling is subject to gouging with pliers. You don’t need to put the gorilla grip to any of the parts when reassembling.

If you bung up the surface with pliers, as long as it will reassemble, the surface damage won’t affect the operation. So, don’t sweat nicks and scratches on the outside.

(If you can build models, you can take one of these apart and put it back together again.)

Often as not, you can remove the entire valve assembly and soak it in lacquer thinner. Work the valve with the trigger stem until it moves freely. Dry out and work a small about of airbrush lube down into it using the trigger stem to work the moving parts. If the obstruction wasn’t too bad, this will usually get things working OK again.

Usually, the most common cause of sticking in the air valve is paint. Be careful with any paint that is spilled on the outside of the airbrush. If it starts to run into the trigger or down into the body, stop and wipe it off. (You can do a detail clean later, just don’t let wet paint run into any area behind the paint cup.) Also, be careful when cleaning the paint bowl and needle that you don’t back-flush thinned paint or dirty thinner / cleaner back into the airbrush body with the needle removed.

With the O-rings (part 50-046), the trick to keeping it serviceable is to always remove the needle for cleaning by pulling from the rear of the handle. Don’t push the needle out of the front of the airbrush. In operation, an annular ring of dried paint will build up on the needle behind the O-ring. This is normally OK, since when the needle is fully forward to close the paint tip, this ring of paint just rests behind the O-ring. However, if you remove the needle by pushing it out the front (through the air and paint tip area), this ring of dried paint works like a rasp as it is forced through the O-ring. Not good. So, pull the needle out of the rear of the handle. Clean it. The reinstall forward back through the handle.

Apply a sparing amount of airbrush lube to the shaft of the needle to the rear of the taper. This is the part of the needle that passes through the O-ring and also through the stem of the trigger. Bot of these are wear points (and the O-ring seals paint from entering the handle and getting into the air valve). You don’t need lubrication on the tapered portion of the needle where it passes through the paint cup and into the paint tip.

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You pull the needle out to the rear? I was taught to pull it out through the front, to avoid pulling paint into the bushing 50-046. Then I clean that bushing with a twist of kitchen towel fed in from the front (with the nozzle removed!) to make sure there’s nothing in that bushing before reassembly. I tend to also push the needle in again from the rear, blunt end first, to act as a cleaning rod just in case. I’ve never had a crusty ring of paint build up on the needle behind the bushing…

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With Badger brushes, they only come out from the rear. There’s a coloured ball on the end of the needle, silver for medium, blue for fine. My stand-in NeoEco (horrible trigger action) has a forward exiting needle, but I haven’t stripped it yet.

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Impressive and very detailed response. Thank you. The air valve action seems fine, in fact the brush works great
Until you put the needle cap (part 41-033/034) on………

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Always to the rear (unless the manufacturer explicitly instructs to remove from the front). Look at the arrangement of the parts and their relationships with each other. Anything that has collected on the needle will be dragged through the O-ring if the needle is taken out from the front.

There is always a very slight amount of paint that will be pulled through the O-ring every time the needle is opened up (i.e. moved to the rear). This paint builds up around the needle to the rear (handle side) of the needle. In operation, when the needle is returned forward (to close the paint tip), this paint is pushed into a ring around the needle, building up over time to form a ring of dried paint. The amount of this is dependent on how often the airbrush is cleaned, but every time the airbrush is used, it grows until it is cleaned off the needle.

(If you clean regularly, the is usually almost no paint on the needle. However, if you paint for a long session or skip cleaning the needle between sessions, there will be paint built up on the needle. If you pull the needle out through the front, the paint that was built up on the needle will possibly be scraped off on the handle side of the O-ring and thus appear to never have been there. If you clean every session, this paint is likely not full dry or cured which can mitigate the onset of the problem. However, abrading the O-ring and leaving paint residue in the handle will eventually result.

Just after operation, the paint on the needle on the cup side is still fluid, so it causes no abrading problem with O-ring. Of course, if someone allows the paint in the cup to dry or they don’t clean it well - rinse and spit -, paint will also build up on the needle on that side, too. The solution for that is to fill the cup with lacquer thinner and allow it to soak and clean as best as possible before disassembling the needle.)

A lot of paint sprayers and some airbrushes will not even allow the needle to be pushed or drawn out of the front (their needles are made with collars on the needles that interact with the trigger to give the trigger more leverage over stronger needle return springs). They can only be removed from the rear. However, most airbrushes don’t have collars built onto their needles (because the return springs are relatively weak or the needle is captured by a lock nut that works by screwing in and out), so, mechanically speaking, those needles can be taken out from the front. If the needle is clean, no harm, no foul. However, if the airbrush has been used, the needle is not clean, and some amount of fouling will be dragged (or forced in the case of dried paint) through the O-ring (sometimes called the “packing” or “packing seal”).

The simple (and correct) way to avoid this possible damage is to take the needle out through the rear of the handle. Once the needle is cleaned, because of the tapered tip, it actually reassembles easier by reinstalling from the rear towards the front.

As mentioned, above, the place to lubricate the needle is on the shaft to the rear of the taper. This lubricates the slot in the trigger stem and the O-ring (and also helps to seal the O-ring). If you were to reinstall the needle from the front, the lubrication would be wiped off the needle on the cup side of the airbrush and none of it would make its way to the slot in the trigger stem. (It would also contaminate the paint - a very small and probably trivial amount - since it would be on the cup end of the needle).

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Not all of them have the balls on the ends to prevent them from being pushed out the front. That is actually a fairly recent Badger feature. However, it does emphasize that removing the needle to the rear is the correct procedure.

My answer was for the OP, RB-101, who described his problems as being with the air valve (sticking) and the O-ring (not lasting long).

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Apologies. I was too caught up in your reply to even see it wasn’t to me. Based on what you’ve said I’ll definitely remove the NeoEco needle from the back. I just wish the plunger action on the trigger wasn’t so l o n g and notchy.

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That’s not the name of that part. I was using your term for continuity.

That’s the one that I was suggesting to back off.

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So, loosening it a half turn might help? I’ll check that when I get down there this afternoon.
Thanks

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Interesting - my Badger Renegade Krome has no ball on the needle, so it comes out easily forwards. I’ve never had paint dry on the needle behind the bushing (it’s not an O-ring on the Krome, but a cylindrical nylon bush) but then I do clean everything long before it could dry on. Back in the day, when I used to draw the needle out to the rear, I got a little tired of it adding paint inside the clamp at the rear where the needle gets secured. That’s because it would drag paint from the cup through the bushing and the rear-end mechanism on its way out. Of course once everything is clean and the nozzle re-attached the needle gets inserted from the rear and gently pushed home…

Now I’ve never used a big paint sprayer, so those might indeed have designs that can only be withdrawn to the rear. And they may have O-rings (rather than the Krome’s bushing) that can e damaged.

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My first airbrush, cheap Kager copy of the Badger 150, had an O-ring where the Badger had nylon or teflon bushings …
The O-rings got squashed and eventually turned hard …

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No offense taken. These discussions often take off in a lot of different directions, which is cool. As often as not, there’re usually a number of new aspects or takes on the original topic, so there’s always something to learn.

I don’t have any specific experience with a “notchy” acting trigger, but I might suggest taking it apart to see if there’s not some sort of burrs or tooling marks on the parts that are interfering with smooth travel. The remedy might be as simple as filing or polishing a couple of small areas.

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That’s the normal part on every Badger that I’ve ever seen. At one time, in a Galaxy far, far away…, authorized Badger dealers were given a small tool so that they could replace those cylindrical needle bushings at the point of sale (as a warranted repair). You could even buy the tool from Badger along with packets of the bushings to do it yourself.

It’s still not too hard to replace the bushing yourself. (I believe that you can still order the replacements.) It uses a slight interference fit.

The older Badgers also had another cylindrical bushing that fit between the paint tip and the body. Those were just a slip-fit and easily lost. Again, you could buy packets of replacements to keep on hand. If someone still has one of those older Badgers but has lost this bushing, a smear of lip balm on the threads of the tip will usually seal it. This bushing prevents air in the tip from bubbling back into the paint cup in normal use. So, if someone is getting bubbling or foaming in the paint during normal use, try putting a bit of lip balm (or bee’s wax) on the tip threads next time you reassemble after cleaning.

You’re right about pulling the needle out with paint still in the cup. FWIW, before removing the needle, I pour out any remaining paint (either save or discard), clear the tip by spraying until I just get air, and then add some thinners. I’ll agitate and rough-clean the cup and pour that mess out and flush spray to clear the tip again. Usually by this time, there’s only some residual paint left, so at that point, I’ll take the brush apart for detailed cleaning.

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I have a replacement bushing somewhere! Thought I might need it, but so far I haven’t. I agree about rinsing/flushing as much paint out as possible before any disassembly! But i find no matter how clean I think it is, I always get the needle smeared by paint lurking around the front of that bushing. Nothing short of disassembly and application of paper-towel twists can get at it the way they recessed that little sucker!

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I deep cleaned the Badger today, in stripping it (again) I noticed the body was now completely blocked by something that I couldn’t push out. Soaked it in IsoPro 90 then Laquer thinner for awhile and with more scrutiny, two pieces of what looked like cardboard were in the body immediately below the trigger slot. Some more swishing and they both washed out. Reassembled it and blew some distilled water through it (with the end cap fully tightened) then some Vallejo cleaner. Both went through well with 30 psi set on the compressor. Didn’t get the time to run any paint through but I will later in the week. Inginual hernia surgery tomorrow so no hobby for a day or two.
Maybe this is progress!

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Glad it’s better. I’ve paint residue take on some strange characteristics. Not in my airbrush but in bottles.

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Good luck with the surgery.

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Thank you. I appreciate your advice on this. It’s been helluva frustrating.

Denimo

ETA I’m wrong about the wash. I used Laquer thinner.

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Thanks Greg. Had the first one fixed earlier this year.

That was a cruise. Hope this works out too.

Cheers

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Best wishes for the surgery!

I’m intrigued how two bits of cardboard got into the AB - bits of its original packaging perhaps? Still, now they are gone let’s hope it behaves itself!

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