Spray Etching Machine

[mixos1]

Do you have any ideas on how to make a nozzle or a complete system that will spray water (or etchant?) continiously? If the system could be etch-resistance (plastic parts in touch with fluid) then it can be perfectly be used as a nice spraying PCB etching machine.

View attachment 35461

 

[ante1]

Hi Mike,

That

 

[Dazza]

That's a great idea mixos, and I already have 95% of the equipment and materials to put it together.
You could use a low pressure spray gun, that works on a venturey system, I have several of these spray guns, two of which can be easily modified to be noncorrosive.

Hang on a minute, I have a better idea, I bought a windscreen washer universal replacement kit, that thing that squirts the water onto your windscreen, a couple of years ago, it consisted of a 12v electric pump motor, a couple of lengths of clear plastic hose and two small plastic spray nozzles, the spray nozzles I still have some where. I think this would do the job nicely, the only thing corrosive is the motor shaft connected to the impeller of the pump. All you need to do is use a seal container, like ante suggested maybe made of glass, and mount the nozzles inside in a way so that they would automatically travel from side to side. Connect a hose at the bottom to the pump and then to the spray nozzles. So then it would recycle the solution. The only real difficult part would be a mechanism to move the nozzles.

These 12V pumps need to be mounted below the water level, because they are gravity fed.

 

[ante1]

Why not a windscreen viper motor? ;D

BTW.

A fuel injector nozzle will give a high dense of moist (like fog) at very low fluid consumption. The drawback is that it takes a pressure of a few bars to open it.

 

[mixos1]

A windscreen's nozzle doesn't seems to work because it doesn't actually "spray" the water but shoot it in an almost straight line. I think the best nozzle could be one like garden's watering nozzle (maybe turning also) or a glass detergent bottle nozzle. Also, a mechanism from dish washing machine could do the job.

The fuel injection system seems to be not the easiest way and maybe it isn't etch resistant.

After a succesfull nozzle selection there is need for a powerfull pump that will recycle the fluid. Maybe one for windscreen clearing system could be nice.

That's good news Dazaa! The traveling mechanism is a nice idea! and for sure it is the most difficult to build! It must also be from etch resistant material!

That construction is a challenge!

 

[gsmaster1]

You may use a windshield pump and a sprayer like these azax bottles that are plastik.

These sprayers usually have a metal valve in them but we dont need it because it is used only for pumping the liquid from below. Maybe it is nessesary to keep the lever pressed in order to allow fluid to be sprayed.

You will mount the windshield pump to the pipe that usually is in the bottle.

You can find bottles like this in supermarkets (mixo, o masoutis exei...), they are used in gardening, to spray the leaves with water... they are cheap and its nozzle is adjustable from straight line to almost mist... I use one of them to spray the boards with water after etching... it is very handy...

 

[Dazza]

mixos, I just realised something ;D, I think this is a really good, (inventive/new idea) a true (bright idea).

I think this would be a very useful/popular project to build, so I think it would be good to keep in mind, the (mechanical construction/hardware) and try to use commonly available materials, and try to keep the construction method as simple as possible.

Oops, did I just suggest that mixos, may have posted in the wrong place, that was a bit cheeky of me wasn't it.

[move];D ;D ;D 8) 8) 8) ;D ;D ;D ;D ;D ;D ;D[/move]

 

[Dazza]

I think it is very important that the etching solution is applied to the PCB evenly, and the pressure is applied evenly to the entire PCB to be etched, to ensure the etching process takes place evenly over the entire board.

You don't want to end up with a small area on the PCB that takes twice as long to be etched, this will run the risk of wearing off the etch resistant material.

 

[mixos1]

The issue of evenly PCB etching can be solved by adding a traveling mechanism that will be parallel to the board. That's a challenge also.

That's for sure a great idea that will help a lot, we will try to use common and easy to find materials.

Azax bottle sprayer is a good idea. Maybee some first tests can be done with it.

 

[rybitski]

keep in mind what ever pump you use should be made of plastic or else it will corrode... A submersable pond pump would probably be a better solution, and the best part they are cheaper than a windshield washer pump. (In the US anyways)

 

[allado]

pressure by pcb etching is around 20 to 30 psi... and bomb is revisted with propilene.