At last, the etching has been done, the holes have been drilled and the last task before soldering the components, is to finish the PCB so that it looks as professional as possible.
First, the oversize board can be cut to size, using a hacksaw or similar. Make the saw cut just outside the copper board edge, to allow for filing/smoothing of the rough cut pcb edge. Take care not to rub fingers and hands against the rough PCB edges, as the glass fibres are so fine, they can enter the body! Similarly, do not breathe in dust generated when drilling, cutting or filing the board.
The board should now be cleaned as described in the earlier page, but if this has already been completed, then a light rub over with a fine, waterproof, abrasive paper should be carried out.
The board, with shiny copper tracks, is now ready for assembly and soldering. After this has been completed, and basic functional testing carried out (to spot the stupid mistakes), the bottom surface should be coated with a protective lacquer, to prevent oxidisation of the tracks, over time. This should be done as soon as possible after component assembly.
A better approach (which does not always look so good!), is to 'tin' the copper tracks before component assembly. This takes some practice, if a messy result is to be avoided, but the key to success is heat and flux!
Smear a THIN layer of plumbers flux across the surface to be tinned, then using the soldering iron and the minimum possible solder, work the solder accross the pads and along tracks as quickly as possible. Avoid using too much heat on thinner tracks to avoid damaging them. Finally, inspect the board for solder bridges between tracks and pads - a small magnifier may be useful for this task.
The flux is messy and this is best removed using cellulose thinners, in a well ventilated area., followed by a wash with soapy water. A protective lacquer is not needed with tinned boards, but will enhance appearence, if applied to the finished board after components have been assembled and soldered.
The picture here shows a tinned pcb ready for cutting and finishing.