- Cut the copper-clad laminate to the size required by the PCB
- Put the stencilpaper on the steel plate, use a pen to draw the circuit diagram on the stencil paper (diagram size should be 1:1), cut it out according to the PCB size, and place it on the copper-clad laminate. Take a small amount of paint and talcum powder into a suitable printing material, dip the printing material with a brush, and evenly apply it to stencil paper. Repeat it several times. Then the circuit can be printed on the printed board. This printed board can be used repeatedly and is suitable for small batch production.
- Use 1g of potassium chlorate and 40ml of 15% hydrochloric acid to prepare a corrosive solution, and then apply it to the printed board where it needs to be corroded for corrosion.
- Wash corroded printed boards repeatedly with water. Wipe off the paint with banana oil, and then wash it several times to clean theprinted board without leaving corrosive liquids. Apply a layer of rosin solution. Let it dry before drilling.
There are many ways amateurs can create PCB, but they are either time-consuming, complex in “craftsmanship,” or low quality. This method of making PCB is one of the methods with a better overall effect. The method is as follows:
- Printed circuit board diagram. The pads in the figure are represented by dots, and the connection can be a single line, but the position and size must be accurate.
- Cut the printed circuit board according to the circuit diagram’s sizeand clean the surface of the copper foil.
- Use carbon paper to copy the diagram to the printing board. If the circuit is simple and the producer has extensive board-making experience, this step can be omitted.
- Depending on the components, paste standard pre-cut symbols (pads) with different inner and outer diameters. Then stick tape lines of different widths according to the current. Electronic stores provide standard pre-cut symbols and tape. Common specifications of pre-cut symbols include basic materials such as D373 (0D-2.79, ID-0.79), D266 (0D-2.00, ID-0.80), D237 (OD-3.50, ID-1.50). Try not to use (black) and plastic (red) materials. The general specifications of tape are 0.3, 0.9, 1.8, 2.3, 3.7, etc. The unit is millimeters.
- Use a softer hammer, such as smooth rubber, plastic, etc.,to hit the sticker to make it fully adhere to the copper foil. Focus on the turning and overlapping of the line. It is best to use a heater in cold weather to heat the surface to enhance the adhesion effect.
- Put it in ferric chloride to start the corrosionprocess. Be noted that the liquid temperature cannot be higher than 40° After corrosion, it should be taken out and rinsed at the correct time, especially if there are thin lines.
- Make holes, polish the copper foil with fine sandpaper, apply rosin alcohol solution, and let it dry. The quality of this printed board is very close to that of a conventional printed board. The 0.3 mm tape can be passed between the two legs of the IC, which can greatly reduce the short jumpers on the front of the circuit board, thus saving trouble and time.
- Dissolve lacquer flakes (namely shellac, available from chemical stores) in three parts of absolute alcohol, and stir appropriately. After all the flakes dissolve, add a few drops of medical purple potion (gentian violet) to make it show a particular After evenly mixing, it can be used as protective paint for the circuit boards.
- First,polish the copper-clad board with fine sandpaper. Then use the duckbill pen in the drawing instrument (or the ink duckbill pen used to draw graphics on the compass) for drawing. There are nuts on the duckbill pen to adjust the thickness of the stroke. You can also use a triangle ruler to draw thin straight lines. The drawn line should be smooth, uniform, without jagged edges, giving people a smooth and fluent feeling. You can also write Chinese characters, English, pinyin, and symbols in the free space of the circuit board.
- If the drawing line penetrates the surrounding environment, the concentration is too small,and you can add some paint chips. If the drawing line does not stretch smoothly and becomes too thick, you need to drop a few drops of absolute alcohol. It doesn’t matter if you make a mistake. Just wipe it off with a small cotton swab dipped in absolute alcohol, and then redraw. After drawing the circuit board, it may corrode in the ferric chloride solution. After the circuit board is corroded, it is very convenient to remove the paint. Dip a cotton ball in absolute alcohol to wipe the protective paint to dry, and then apply rosin.
- Because the alcohol evaporates quickly, the prepared protective paint should be sealed and stored in a small bottle,such as an ink bottle. Cover the bottle cap after use. If the concentration becomes thicker in the next use, add the appropriate amount of anhydrous alcohol to dilute the solution.
- Paste the self-adhesive labels on the copper foil of the copper-clad laminate, then draw the circuit on the veneer. Use a cutter to cut the veneer to form the required circuit, remove the non-circuit parts, and finally use ferric chloride to corrode theideal circuit board.
- The corrosion temperature can be performed at about 55°C, and the corrosion rate is more rapid. Rinse the corroded circuit board with clean water, remove the self-adhesive labels on the circuit board, make holes, wipe clean, and then apply rosin alcohol solution prior to
- Arrange the components’ density and positionaccording to the shape of the components used in the schematic circuit diagram and the size of the printed board area. The components‘ location should be determined according to the principle of large first, then small, first overall, and then local. The adjacent components in the circuit are placed nearby and arranged neatly and evenly.
- The connecting tracebetween components cannot be bent at right angles at the corners or intersections of the two traces. They must transition through a curve, and they cannot cross each other and turn too far. When certain traces cannot achieve this, you can consider placing printed trace on the back of the printed board and then using stud bolts to connect to the front circuit. Another solution is to use insulated trace when soldering components.
- The distance between the input part and the output part is better to avoid mutual interference.
- Print the circuit board diagram on the printer at a ratio of 1:1 on 80 grams of copy paper. Hand drawing is also possible, but the bottom paper should be flat.
- Find a fax machine, take out the fax paper from the machine, and replace it with a hot-melt plastic film. Put the circuit diagram into the fax machine’s outgoing fax trayand use the copy button to copy the circuit diagram on the hot-melt plastic film. At this time, the “printed manuscript” of the printed circuit board is ready.
- Use double-sided adhesive tape to affix the drawn plastic film to the copper-clad board evenly. The plastic film and board shouldbe flat and not wrinkled. The tape paper can not cover the melted part. Otherwise, it will affect the production quality of the circuit board.
- Use a paintbrush to brush the paint on the plastic film evenly. Note: Only brush in one direction. Otherwise,the plastic film will wrinkle, and the lines on the copper plate will overlap. After the circuit diagrams have been brushed, carefully remove the plastic film. At this time, a printed circuit board is finished. After drying, it can be corroded.
- If you want to print manypieces, you can make a wooden frame that is a little larger than the circuit board, lay the PCB stencil (our company sells it) flat on the wooden frame, and fix it. Then use double-sided tape to stick the fixed plastic film under the screen. Put the copper-clad board on the table, close the screen frame (the printed image and the copper-clad board should be aligned left and right), use a paintbrush to paint in one direction, and remove the screen frame. The printed circuit board is printed. If there is any defect, it can be modified with paint and bamboo.
Pay attention to the above process. When painting, the hand force should be light and heavy. If there is too much paint or the film is too thick, the lines will be smudged. If the force is too light, the lines will break. And the plastic film must face up.