Mini Spray Nozzles and Painting

I am trying to build a robot of sorts that can paint on a glass board. The original idea was to use a marker, but we are afraid that they will not be reliable enough.

An alternative we came up with was to actually spray the paint directly. It would need to be fairly precise - it would be nice if a "pixel" of paint was around 3mm2. We also don't want the paint to drip, so we'll need to be able to have good control of how much paint is dispersed.

Does anyone have experience with spray nozzles that would work well on this scale? If so, where would I be able to purchase the relevant parts?

Why not make a stencil the exact size and shape you want? That will give more leeway in the type of nozzle you can use. You might even be able to get away with using paint from a spray can, if the robot is able to press and depress the top of the can quickly enough (something that a solenoid with a return spring could potentially do).

Thanks for replying.

In answer to your question:

Far-seeker:
Why not make a stencil the exact size and shape you want?

The robot will be printing binary images sent to it on the fly.

Far-seeker:
You might even be able to get away with using paint from a spray can, if the robot is able to press and depress the top of the can quickly enough (something that a solenoid with a return spring could potentially do).

This could potentially work, except that we need to use a specific type of ink that is easily erasable. Maybe there's a way to get that kind of ink/paint pre-packaged as an aerosol.

Thanks again!

Get an inkjet cartridge and see if you can get it to squirt. The small perfume/cologne squirt samples have small spray heads that might be of use.

http://nicholasclewis.com/store/
http://spritesmods.com/?art=inker&page=2
http://reprap.org/wiki/Reprappable-inkjet

Probably find lots more examples with a little google.

Chagrin:
http://nicholasclewis.com/store/
http://spritesmods.com/?art=inker&page=2
Reprappable-inkjet - RepRap

Probably find lots more examples with a little google.

This is great stuff. Thank you!

I am curious whether you have finished the robot yet?
Suggestions for you if you need to know more about Paint Sprayers: https://gopaintsprayer.com/