Airbrush Problems - Iwata CR

[DiscoRover007]

Hey guys so my faithful workhorse airbrush is experiencing some issues and I was wondering what I need to do to service it. Despite cleaning it I find that it will still spray paint even after depressing the trigger and releasing it. It also seems to leak air somewhere as I can hear a slight hissing noise when not in use.  Does this sound like a o-ring seal issue?

 

 

[Matt Bacon]

When you say "despite cleaning it..." do you mean you've taken it apart and cleaned it piece by piece, or just sprayed solvent through it?

"It'll still spray paint after depressing the trigger and releasing it" sounds as if you've got two things going on: the air valve is sticky, and not closing quickly and completely when you release the trigger, AND the needle isn't closing fully so you still have some paint flow...

If when you're spraying normally, you have bubbles back into the the cup as well, that's a nozzle sealing issue.

You should get some "Liquid Reamer" in  can and some lacquer thinner  To clean the tip (3 above), I would  dip a small paintbrush in the lacquer thinner, insert it into the tip until you can see bristles coming through the end, and twirl it around a few times, wipe on paper towel and repeat several times. Then stick the point of the tip into the spray tube of the liquid reamer can, holding it tight, and zap some reamer backwards through the tip. That should then be properly clean inside.

Put some liquid reamer on a paper towel and wipe the needle through it a few times to make sure the tip is clean.

You can try putting some lube (eg Regdab) onto the top of the air valve in the body (below the trigger (10)) and pop it up and down a few times to see if it eases. If not, you're going to have to clean the air valve assembly (21-25). You disassemble it from the bottom of the neck. Unscrew the plate (25) at the bottom (a pair of sharp tweezers inserted into the slot in the brass baseplate will do it). Be careful... there's a spring (24) in there, don't let it pop out or spring the baseplate across your desk. Take the valve apart, and make sure the piston and o-ring (23), inside of the valve body (22) and top o ring (21) are all clean and free of any paint. Put it all back together.

If your tip is clean, the needle is properly seated into it, and the air valve piston moves freely, than your problem _should_ be gone away.

My main piece of advice would be get comfortable taking apart your airbrush, cleaning, and reassembling it properly. they aren't magic, or even particularly complicated, but they are precision appliances, so it's worth really understanding what's going on if you want to be able to fix it!

Good luck!

best,

M.

 

[BigTallDad]

The needle might be bent. Remove the needle and roll it on a very flat surface; if the tip wobbles, the needle is bent and may need to be replaced.

[Pete J.]

Just out of general principle I would replace the needle seat(seal or part #9 in the above diagram).  If your air valve is sticky, it may have gotten some paint back through that seal.  I would first take the air valve apart and clean it a lube it.  Make sure it works properly.  Then a through cleaning of all the chambers and nozzles is in order.  The inside of the brush should be totally clean.  No paint anywhere. 

Also, on reassembly,  be sure you use some airbrush needle lubricant.  I like the blue gel by Iwata, but there are a lot of other lubricants out there.  They are designed to work with an airbrush without contaminating the paint.  Everytime I take the needle out to clean it I always lubricate it.  Helps the seal last longer and the trigger action is much smoother.