rons
Diamond
- Joined
- Mar 5, 2009
- Location
- California, USA
The circuit board was in plastic tube and the tube was rocked back and forth. Always the etch ends with a circle in the center? WHY?
The board was etched away in phases. At the end of a 5min etch/agitation the board was rinsed and dried. Then instrument lacquer was
brushed over the completed traces from that phase. Repeat. Some of the outside traces have bleed the black dye I used to touch up the
traces before the first etch. But the underlying copper is sealed from further etching. Keeps under-cut from happening to the outside
traces as I wait for the inside parts to get done.
Tin plating solution works by just soaking circuit board in solution for 3-5 minutes. What is this layer of white sand at the bottom of the container.
It's about 1/4 inch deep. I poked a dowel into the sand and tried to mix it into solution. Some of it did break apart but what is still left at the
bottom will not mix into the solution any more. WHY?
The board was etched away in phases. At the end of a 5min etch/agitation the board was rinsed and dried. Then instrument lacquer was
brushed over the completed traces from that phase. Repeat. Some of the outside traces have bleed the black dye I used to touch up the
traces before the first etch. But the underlying copper is sealed from further etching. Keeps under-cut from happening to the outside
traces as I wait for the inside parts to get done.
Tin plating solution works by just soaking circuit board in solution for 3-5 minutes. What is this layer of white sand at the bottom of the container.
It's about 1/4 inch deep. I poked a dowel into the sand and tried to mix it into solution. Some of it did break apart but what is still left at the
bottom will not mix into the solution any more. WHY?