Primeiro imprimia o desenho da placa numa folha de acetato.
Essa folha era colocada por cima de uma placa foto sensível e colocada sob luz UV durante uns minutos.
De seguida essa placa era submersa numa solução com soda caustica para retirar a pelicila foto sensivel que ficou “danificada” com a luz UV.
A placa era depois submersa numa solução com ácido pre-coloreto de ferro.
Após uma lavagem para retirar os quimicos era necessário recortar a placa e por último furar os pads.
The PCB manufacturing method i used before buying my CNC machine was the lithography method and worked as follows:
First i printed the board design on an acetate sheet.
This sheet was placed over a pcb with a light sensitive coat and placed under UV light for several minutes.
The pcb was then immersed in a solution of caustic soda to remove the photo sensitive material that was “damaged” with the UV light.
The pcb was then immersed in a Ferric Chloride solution to remove the copper.
After the copper being removed i then washed the pcb to remove the chemicals and then i needed to cut the plate and finally drill the pads.
O resultado final era muito bom e com este método consegue-se muito boa resolução com vias muito finas mas demora imenso tempo a fabricar e dá imenso trabalho.
The result was very good and with that method i could archieve a very good resolution with very fine lines but it is very time consuming and gives a lot of work.
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