hi,

i am planning to make a low - cost diy etching tank out of a small rectagular acquarium (large enough for hobbyist size pcb's).

my dad has an old 12v air pump used for car tires. i think the pressure of that would be enough to bubble the solution for the pcb.

here is the setup:

• the acquarium would contain the ferric choloride mixture

• i would lay down pvc tubings with holes below the acquarium. this is where air would come out to agitate the liquid. of course the pump would stay outside the acquarium

• there would be more than 1 pvc tubings below. these would be linked to each other using elbow joints and t-joints

the problem that i am now facing is heating the solution.

• how can i continuously heat it safely? acquarium glass is simply an ordinary glass which will break due to too much heat.

• how much heat would be required to heat up the whole solution?

i would also place a diy temp controller depending on the heating element that will be placed.

 

fish tank heater

 

Halogen lightbulb.

 

:? you have a fish tank, so as in the reply above, a fish tank heater would be the Obvious choice :?

 

Yes, i agree a fish tank heater is what i use and remember it doesn't have to be on all the time because the solution only has to reach 50 degrees C.

 

there are some thermostatic fish tank heaters as well, so you can just 'dial' in the required temp, then when the neon goes out - the solution is at the required temp

 

Big glass test tube, with high wattage wire-wound resistor inside, rubber bung etc for cable out. Glass thermistor, epoxy protected, suspended in the solution to monitor temp, and control on/off power to resistor.

Been threatening to build this for my self for many moons.

I still end up bunging a jug in the microwave and warming it that way mind you most of my PCB's could be etched in a tea cup

Note: I don't use ferric, it's not too keen on the microwave, plus I always manage to stain something prefer the clear fine-etch stuff.


Steve