The stirring mechanism from my old etching tank was broken again. Therefore I decided to make a new etching tank. This time a spray etching tank.
I started with making a double bottom on an square bucket. I drilled some holes in that bottom. Two of the holes are for guiding the pump tubes. The rest is to allow the etchant to drain back down.
I used some pneumatic tube for the pump. I heated it to give it a spiral shape. Then I turned it into a tube. I’m going to drill some holes in the side of the tube, for the etchant to come out. The tube is coupled to the motor with a piece of coax insulation.
I have tried a few ways to mount the motors.
First a used some threaded rods.
I used some plastic spacers to mount the rods. This way the etching fluid can’t come in contact with it.
But after some testing this way turned out to be not
At a second attempt I used some aluminum to make it stronger.
Then I came across of a big bar of pvc while cleaning up. This was the result after drilling a few holes:
This is as sturdy as the aluminium, but doesn’t dissolve in the etchant.
I did a dry test with it: