Spraying Metallics

[MrProd]

I've recently had a problem with my procon PS270, where it was flowing a very small amount of paint when the air was on, without any pull on the trigger. I cleaned everything thoroughly with Mr Tool Cleaner, no effect.

I checked my needle and nozzle tip and with x3.5 magnification I couldn't see anything, but I carefully polished the needle anyway, no effect.

Bought a new nozzle tip and bingo! problem solved.

 

Thanks to air-craft.net for sending it out so quickly, great service, as always.

 

So my questions, is it possible that spraying tamiya xf56 through a 0.2 nozzle has left some 'glitter' in the nozzle that is preventing the needle from sitting flush?, and how will I remove it?,  the smallest cleaning brush I have won't fit. Needless to say it's currently soaking in a pot of tool cleaner. 

 

Would any damage/deformation of the nozzle mouth be visible with x3.5 magnification? I think I've been careful when cleaning but if its the nozzle mouth that's the problem then I know it's my fault and I'll be even more careful in the future.

 

Thanks

Jon

[bmwh548]

The nozzle tip can "de-calibrate" in time due to the needle constantly hitting it - which is what happens if you tend to release the trigger suddenly. I'm guilty of it when I try to eliminate some crap from the nozzle or when I flush it with thinners. If you put a brand new nozzle and the old one next to each other you can sometimes see a visible difference in the hole diameter.

Here's a comparison (they are both 0.4, old one on the left).

 

What I used to do when cleaning the microscopic nozzles: grab some cotton (preferably the one that comes in bulk, but you can pick some off of a swab), make it into a long, very thin piece, soak it with the appropriate thinner (lacquer would work for you) and gently push it into the nozzle using an old airbrush needle. Don't force it, you don't want it bulking up inside the nozzle. You want to gentle push it so that it starts to protrude trough the nozzle tip. When it does just pull it through with a tweezer. You can add some more thinner when the cotton is in place (since lacquer evaporates quickly it could dry up before you can get it through). I was always amazed to find colors that I forgot about.

[dogsbody]

Though I've had no issues yet and have only been using my Badger 150 since August, I clean out the tip with a narrow strip of paper towel dipped into some 99% ISO.

I try to make a long thin point on it and push it into the tip as far as possible. I couple of times I have also thinned down a wooden toothpick to as fine a point as possible and let it soak in the ISO for a few minutes, the gently used that to do an easy ream of the tip. 

 

So far, I've had no tip leakage.

 

 

 

Chris

[Greg B]

Have a look for paper points on eBay. Far better to use then pushing an old needle up there.

 

https://www.ebay.co.uk/b/Gutta-Percha-Points-Absorbent-Paper-Points/257837/bn_7025947124

[MrProd]

Thanks for the replies. Thinking about how I've been operating, I'm pretty sure I've deformed the nozzle with clumsy technique. I'm always careful re inserting the needle after stripping it down but I think I've been a bit careless when blowing thinners/cleaner and haven't been letting the needle return gently. 

 

Lesson learned

 

Thanks all.