The stupid spray can problem! #solved!

[rock soderstrom]

I have one thing here that really annoys me. I use soldering enamel from a spray can to coat my self-etched PCBs. It's great, the tracks are protected against corrosion and the soldering is well supported.

What's the problem? You need relatively little of it, the spray can would actually last forever. Unfortunately, it loses its propellant gas relatively quickly and thus becomes unusable. Stupid!

The cans cost quite a lot of money (14€ plus shipping) and it's a shame if you have to throw away more than half of them even though the actual contents are still perfectly good.

What can I do? Does anyone have experience with this? I could open the cans manually and take out the contents to reuse them. What could I use as a new container? I guess the contents of the can will harden under the influence of oxygen, which of course should be avoided.

Any suggestions?

 

[k brown]

I assume you're tallking about conformal coating?

You could just buy it in liquid form and use these:
https://www.amazon.com/Preval-0225-...4342299&sprefix=preval+sprayer,aps,383&sr=8-1

 

[gyraf]

..you sure it's a loss of pressure, not just clogging of the nozzle/delivery-system? When I used (exactly) these regularly many years ago, I would keep/store the nozzle separately in a small bottle with isopropanol/cleaning alc, and spend time unclogging the feed tube every time also...

 

[Script]

Maybe try cleaning the can's noozle after use by releasing some gas with can held upside down. Not sure all cans work the same though.

 

[rock soderstrom]

..you sure it's a loss of pressure, not just clogging of the nozzle/delivery-system? When I used (exactly) these regularly many years ago, I would keep/store the nozzle separately in a small bottle with isopropanol/cleaning alc, and spend time unclogging the feed tube every time also...

Maybe try cleaning the can's noozle after use by releasing some gas with can held upside down. Not sure all cans work the same though.

OMG, I think you're right. I will definitely try that out. I had tried to clean the nozzle from the outside but the problem seems to be internal. I'll give the nozzels a good drink now to clean them...

....it really felt (and sounded) like the propellant had evaporated, but after I installed another cap provisionally, I had function! The spray caps are all different, the spray angle and the size is not right but it works!

Guys, you saved me a lot of money!

PS: What a sticky mess!

 

[gyraf]

yup, if you mechanically clean the nozzle, you usually damage the evenly-spraying functionality

 

[GussyLoveridge]

When you're done spraying your boards, tip the can completely upside down and spray onto a piece of cardboard or other until you're just getting gas out of the nozzle and no paint.

I have been doing this with great success for years now. I don't store the nozzles separately, nor do I clean them with any solvent.

 

[Disco Volante]

I second Gussy's answer. Should they get clogged, a soak in nail polish remover usaually does it.

I regularly refill cans of spray-lube with pressure from the airgun. This of course requires access to a compressor..

 

[rock soderstrom]

Maybe try cleaning the can's noozle after use by releasing some gas with can held upside down. Not sure all cans work the same though.

When you're done spraying your boards, tip the can completely upside down and spray onto a piece of cardboard or other until you're just getting gas out of the nozzle and no paint.

I have been doing this with great success for years now. I don't store the nozzles separately, nor do I clean them with any solvent.

I second Gussy's answer. Should they get clogged, a soak in nail polish remover usaually does it.

This seems to be the recipe for less trouble with clogged nozzles. To be honest, the manufacturer even writes this on the can! (...who reads that? ). I've known this stuff since my first apprenticeship, back then we didn't have the problem because we all used this can together and it was therefore empty faster than the nozzle could clog.

 

[JohnRoberts]

They clearly need to sell smaller cans...

JR