I created all of my PCB prototype manually, so why I must drawing the layout with a big track, in fact that software program already preserved the autotrack function. This function will draw the layout automatically, but the track and the gap are very thin, and it is very difficult to draw it with the hand. Because the gap must be streched and the track must be a little thick, the square of PCB also increased. I didn't implemented this autotrack function. If someone feels that it is a pity to used such the PCB area and location to be mounted, please modify the protel source data which included in the zip file. Also note that, commercial maker (board maker) can do such a little thin layout.
Here how I make my PCB :
- Print the pad layer, PCB layer (both side if double layer) with the ratio 1:1 on the paper.
- Cut the PCB accordingly with the size. Cut the flake on the side or use abbrassive materials to clean it.
- Clean the copper side of PCB (both side if double layer). I usually clean it with soap powder (like "Vim") or use a copper cleaner (like "brasso" or "autosol"), and don't use an abbrassive paper, because the copper layer will be scraped and the surface will be scratch. After that rinse with soap and water and then dry out.
- Place the pad hole layer paper to PCB (copper side) and glue it with adhesive tape. Note that which is the solder side and which is the top side (for both layer, only one needed). Give a notch for every hole with sharp pointer. Usually I used a sharp wall nail or a little chisel. Don't foget to notch for even a one hole, then drill it all with 0.5 ~ 1 mm.
- After every pad drilled, remove the pad layer paper (we do not need this paper any more, so you can throw it away).
- Draw the layout with ruler or by hand, I usually used an "Artline-70" - a waterproof one, for the thickest lines and "Snowman F-size" - OHP permanent marker, for the thinner lines. It takes about a few hours to draw a medium layout size. The more careful you draw the better the result (don't forget for even a little line). Some people used a kind of lettering sheet (rugos) on any shape, like dot, lines, arch, etc. Its all your choice.
- Many kind of etching technique, I used ferrichloride (FeCL3) because this is very easy to find. Fixed it with water in the ratio of 1 part ferrichloride equal 3 or 4 of water. The composition about 10 cc of ferrichloride for every 100 cm square of copper clad. Usually the liquid concentration like a strong coffee mix with milk or a strong tea. It takes about 10 to 15 minutes (the good etching time) until all the undesireable copper part carried away. When it takes to fast, some covered part will be lost, and the opposite, some undesireable part still remain. When it takes to long, the covered part (the marker) will be erode. Note that don't touch the liquid with bare hand directly, your skin will be erode a little too.
- After all undesired copper has removed, then rinse it with water again. Used alcohol to remove the marker and then rinse it with water again. Dried it up.
- Test the continuity layout with bel check or ohm tester and compare it to the layout print out. If there is a line or more you have forgotten to draw it, then the only way that you must connect it with a jumper wire. Now the PCB is ready to used!
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