Experimenting with Thermal Switches
thermal switches to maintain the temperature of an electroplating solution:-
About Myself: -
I run a business of manufacturing electronics goods for consumers and for trainees’ engineers. A lot of time I prototype double sided PCB in my premises. For plating the PCB holes. I had to build an electroplating setup bath. It is very difficult to judge weather the holes are plated or not if they are not shiny.
Problem: -
Surface plating finish of any metal heavely depends on current density and temperature of the plating solution as shown in the figure bellow.
Figure 1:-
Most factory machine comes with the temperature controller for the machine. But over her, we are trying to build an inexpensive copper plating machine for personal use. We are using a plastic contianer to store and the Copper sulphate pentahydrate as plating electrolyte. This where the problem arises, We want to build an inexpensive machine that takes less time to build. We even have to consider melting temperature of plastic container.
Solution: -
To maintain temperature of copper sulfate and current density based on figure 1. We are building a temperature switch controller to set the temperature of the solution to 60'c. Circuit schematic of the controller is given in figure 2
Over here the power resistor and the thermal switch is sealed and dipped in the copper sulfate solution to heat the solution and to maintain the temperature of the solution.