Method for making pcb by rigid FR4 copper clad board used by DIY players
The designed copper foil pattern is duplicated on the FR4 copper clad copper foil surface, and the special engraving tool grinded with the steel saw blade is directly drawn on the copper clad plate along the edge of the copper foil pattern, and cut into the depth as much as possible. Then, tear off the copper foil that is not needed outside the pattern, and then punch the hole with your hand drill. The key to this method is: the intensity of the painting should be sufficient; the excess copper foil should be removed from the edge of the board. When the operation is good, it can be gradually removed in pieces. You can use small needle-nosed pliers to complete this step. Some small circuit experimental versions are suitable for this method.
It is to use the pen to directly draw the printed graphics on a rigid copper clad plate, and then carry out chemical etching and other steps. This method is very difficult to operate! There are mainly the following reasons: the current electronic components are small in size, the pitch of the leads is smaller (on the order of millimeters), the copper foil traces are also small, and the lines drawn are difficult to modify.
Place a piece of paint (that is, shellac, which is available at chemical raw materials stores), dissolve it in three parts of absolute alcohol, and mix it properly. After all of it is dissolved, add a few drops of medical purple syrup (gentian violet) to make it a certain color, after mixing evenly that can be used as a protective paint to depict the circuit board.
Polish the CEM-3 copper clad board with fine sandpaper first, then use the duckbill pen in the drawing instrument (or the ink duckbill pen used to draw the graphic on the compass) to draw the nut. The duckbill pen has a nut that adjusts the thickness of the stroke. The stroke thickness can be adjusted, and the ruler and the triangle ruler can be used to draw a very thin straight line, and the drawn lines are smooth and uniform without edge serration and give a smooth and fluent feeling; at the same time, it can also be on the circuit board. In the free place, write the lines drawn by Chinese characters, English, pinyin or symbols. If it is infiltrated into the surroundings, the concentration is too small, you can add a little paint piece; if you can’t open the pen, it is too thick, you need to drop a few drops. waterfree alcohol. In case it is wrong, it doesn’t matter. Just use a matchstick, make a small cotton swab, and rub a little bit of alcohol to wipe it off easily, then redraw it. Once the board drawing is completed, it can be corroded in the ferric chloride solution. After the circuit board is corroded, it is very convenient to paint. Use a cotton ball to rub the anhydrous alcohol, then you can wipe off the protective paint. After drying it, you can apply it with pine perfume.
Since the alcohol evaporates quickly, the prepared protective paint should be sealed in a small bottle (such as an ink bottle). Don’t forget to cover the bottle after use. If it is used next time, the concentration will become thicker, just add the right amount. Anhydrous alcohol can be used.