Needle stuck in airbrush

The needle is probably stuck in the needle tube. When you back flush or simply pull the needle out the back of the brush paint can get inside the tube. After it builds up enough the needle can stick. Take the handle off and try unscrewing the complete assembly out. If you can get it out then soak the assembly in solvent. Lacquer thinner if you have it. There shouldn't be any parts in there it would hurt.

Tony

Wingman_kz wrote:

When you back flush or simply pull the needle out the back of the brush paint can get inside the tube. After it builds up enough the needle can stick.

Not if the needle bearing is in good shape.

PZL P.62,

Are you sure you didn't jam the needle into the tip and that is what is causing this problem?  

You are loosening the needle chuck before trying to remove it correct? Just going over the basics.

Wingman_kz wrote:

The needle is probably stuck in the needle tube. When you back flush or simply pull the needle out the back of the brush paint can get inside the tube. After it builds up enough the needle can stick. Take the handle off and try unscrewing the complete assembly out. If you can get it out then soak the assembly in solvent. Lacquer thinner if you have it. There shouldn't be any parts in there it would hurt.

I agree.  I've had it happen several times.  No matter how clean you think an airbrush is there always seems to be some paint left somewhere.  I usually disassemble mine as much as possible (especially the air valve) and soak it in lacquer thinner for a while.  Either that or a few drops of lacquer thinner dropped traight down the needle with the head removed.

MusicCity wrote:

Wingman_kz wrote: The needle is probably stuck in the needle tube. When you back flush or simply pull the needle out the back of the brush paint can get inside the tube. After it builds up enough the needle can stick. Take the handle off and try unscrewing the complete assembly out. If you can get it out then soak the assembly in solvent. Lacquer thinner if you have it. There shouldn't be any parts in there it would hurt. I agree.  I've had it happen several times.  No matter how clean you think an airbrush is there always seems to be some paint left somewhere.  I usually disassemble mine as much as possible (especially the air valve) and soak it in lacquer thinner for a while.  Either that or a few drops of lacquer thinner dropped traight down the needle with the head removed.

That is odd Scott as I have never had that happen.  

MikeV wrote:

That is odd Scott as I have never had that happen.

It's not something that happens "Often", Mike, but I have had it happen several times.  Normally it's the same symptoms each time: Put it up for a few days, get it out and pull the trigger back and it stays back.  Pull the needle out (not always easy!) and there will be a ring of dried paint on the needle in the vicinity of where the needle bearing would be.

Personally I think one of two things causes it.  Either back-flusing, I do that a lot, or pulling the needle out from the rear when there is still paint in the brush.  The needle bearing isn't a complete seal and my guess is that either of those will allow enough paint to get in there to cause it to bind up when it dries.

Admittedly I haven't actually measured the depth to see if it is really where the needle bearing is, but it's real close to that area.

MusicCity wrote:

Personally I think one of two things causes it.  Either back-flusing, I do that a lot, or pulling the needle out from the rear when there is still paint in the brush.

Back flushing should not do that so I would say it is pulling the needle out with paint still in the cup. That is a giant no-no!

The needle bearing isn't a complete seal and my guess is that either of those will allow enough paint to get in there to cause it to bind up when it dries.

Actually the needle bearing is pretty much a complete seal unless it is worn out or the needle is worn out and does not fit properly any longer.

How much back flushing do you do anyhow? I spray out all the paint, spray some cleaner through it and then back flush for maybe 5-7 seconds, spray out, back flush once again for about the same amount of time and then spray more cleaner through it and then some filtered water and that's it. I never have any problems doing it this way.

MikeV wrote:

MusicCity wrote:  Wingman_kz wrote: The needle is probably stuck in the needle tube. When you back flush or simply pull the needle out the back of the brush paint can get inside the tube. After it builds up enough the needle can stick. Take the handle off and try unscrewing the complete assembly out. If you can get it out then soak the assembly in solvent. Lacquer thinner if you have it. There shouldn't be any parts in there it would hurt. I agree.  I've had it happen several times.  No matter how clean you think an airbrush is there always seems to be some paint left somewhere.  I usually disassemble mine as much as possible (especially the air valve) and soak it in lacquer thinner for a while.  Either that or a few drops of lacquer thinner dropped traight down the needle with the head removed. That is odd Scott as I have never had that happen.

There's a first time for everything...

A month or so ago I was painting a car body. Shot 3 coats of pure white and then a couple of wet coats of white pearl and just as I made the last pass on the roof a little fleck of orange came from somewhere and just dissolved right in the middle of that beautiful white. It just kind of spread, layer to layer.

Now it had been at least two weeks since I had shot any orange. I'd sprayed grey primer, black, several Alclads and Metalizers. Even previous coats of white. I'd cleaned the a/b several times. So I tore it apart and started cleaning and ran my little brush through the needle bushing and when it came out, it had orange on it. Granted, the bushing in my 360 could be worn a bit, I use it a lot and it's five years old. But I do try to keep it clean for that very reason. I guess I was a little lax in cleaning that particular area.

I used to take the caps and tip off, loosen the chuck and pull the needle out the back. I'd wipe off the end of the needle before I pulled it but didn't think about the part of the needle I wasn't reaching that was still ahead of the bushing. So, I shot some paint one evening and everything was fine till I went to clean the brush. When I tried to pull the needle it was stuck. It had sprayed fine. Trigger worked fine. Needle wouldn't come out. I unscrewed the needle tube assembly and put some lacquer thinner on it and after a few minutes the paint that was inside the tube softened enough that I could get the needle out. Then I cleaned the inside of the tube.

It's a pretty close fit and doesn't take much to sieze the needle. Paint can build up over time, you clean the brush and get everything damp with solvent/thinner, you put it back together and it sets, everything dries out and the next time you go to use it the needle doesn't want to come out.

Now I make sure to remove the caps and tip, loosen the chuck and push the needle all the way forward and wipe it off before pulling it out the back. Hasn't gotten stuck since. But it still got paint inside and behind the bushing and it came out at a very inopportune moment and ruined a paint job. So, an a/b can't be too clean. IMO.

Hope that helps

Tony