Thermal transfer method
Electronic circuit board is the carrier of any circuit design needs to be mounted on a circuit board, it can achieve its function. The processing circuit board, and an amateur electronics enthusiasts feel most headaches, often is: half a day designed circuit board can be processed but spend a few days time. Even some good circuit design creativity, but because too much time processing circuit board and give up the experiment, can not continue to be achieved. Master began 20 years ago to engage in circuit experiment, most Yun Cai also make circuit boards, can be described as exhausted all means: paint, wax, carbon paper, chisel, even MM are used nail polish, eyebrow pencil or something East East are used, are still not achieve efficient, high-quality production purpose breadboard.
Later, the company engaged in professional design and development, professional engineers who know do not know there is this other difficulties. They used CAD design good drawings, PCB handed out after printing plant, after a few days you can get a good few PCB processing model. Install the part, and then print debug modify, sending PCB processing plant, repeated several times, the circuit is done. They simply do not have to consider the processing circuit board process, various cumbersome process and production costs. The reason for the trouble PCB processing plant, the processing of these companies again free to experiment with the circuit board, and certainly not "carry forward the spirit of Lei Feng", it is clear that these are to be allocated to processing costs of future production costs.
If you are a small unknown company, or individual, and that the cost of processing time may have a few hundred dollars. So, how simple, fast, low-cost, high-quality processing of the experimental circuit boards, is a worthy subject of study. Now have a good number of new methods, such as: thermal transfer method, pre-coated photographic Bonded Copper production method, melt plastic film method. This site will collect methods, experiences, and organize written, published one after another on this site. Also welcomes enthusiasts, manufacturers, material and equipment suppliers and other cooperation, or the author, or provide your product or co-marketing can be.
As described in the preface, is the carrier of the circuit board, usually we call "printed circuit board" abbreviation "PCB". Regular production of printed circuit boards and printed on natural, is commonly used in the screen printing process, the basic process is as follows:
Design layout → trace → drying board (production printing master) → printing → → cleaning chemical corrosion and surface treatment → Printing flux, logos, and other solder layer → cutting, drilling and other machining → finished circuit boards
Other methods
A more detailed look at the site collection steps "method of screen printing circuit board production and instrument panel signs," a text. Amateur conditions, omit the "flux printing, labeling, such as solder layer" processes, difficulties in making and printing sectors. Since only need to make a small (or a few) circuit boards, using a regular plate making and printing process is obviously not the economy, so there is a variety of non-print, or sub-printing production methods.
1, engraving
The most direct this method. The graphic designed with carbon foil, copper foil surface is replicated to the CCL, using special carving tools hacksaw piece milled directly on the CCL force along the edge of the copper foil pattern characterization, try to cut into the depths, then torn beyond graphics unwanted copper, call on the component jacks on it. The key to this method are: To characterize the intensity enough; torn from the edge of the excess copper plate started, the operation is good, a sheet can be gradually removed, the scissors can be used to complete this step. Some small circuit suitable for this method produced an experimental version.
2, hand-painted Law
Is the pen directly printed graphics painted on the CCL, then chemically etched steps. This method appears to be simple, in practice it is not easy! Now small electronic components, pin spacing smaller (millimeter), copper traces are also small, and painted lines also difficult to modify, to draw such a good look at your plate is completely written work of the . Experience is: "pigment" and brush selection are critical. I myself have used red nail polish in a medical syringe loaded, depicting a circuit board, the effect is good, but the tip of the needle to the proper processing; has also been introduced with paint flakes dissolved in anhydrous alcohol, use duckbill pen sketch, as follows :
The paint flakes (ie shellac, chemical raw materials store sale) of a dissolved three anhydrous alcohol, and appropriately stirring, until all dissolved, a few drops of medical gentian violet (gentian violet), it presents a certain color, stir, can be used as a protective lacquer painted circuit boards. First with fine sandpaper to polish the copper-clad, and then using the drawing pen drawing instruments (or compass used to draw graphics on the ink drawing pen), be depicted, adjust the nut on the stroke thickness duckbill pen stroke thickness adjustable, and can borrow ruler, triangle ruler depict a very fine line, and lines depict the smooth, uniform, no jagged edges, giving a smooth, fluent feeling; can also idle at the circuit board write Chinese characters, English, Pinyin or symbols depict the lines, if the surrounding infiltration is the concentration is too small, you can add a little paint flakes; If the trailer is not open pen, it is too thick, you need a few drops of ethanol . In case description was wrong does not matter, as long as a stick (matchstick), make a small cotton swab dipped in ethanol one o'clock, you can easily erase and then re-rendering can be. Once the circuit board illustrations, After, ferric chloride solution to corrosion. After the circuit board corrosion, paint is also very convenient, with a cotton ball dipped in ethanol, it can be erased to protect the paint, a little dry, you can use along with painted pine fragrance.
As the alcohol evaporates quickly, the prepared paint protection should be placed on the vial (eg inkwell) sealed after use, do not forget to cover the cap, if used in the next, found that the concentration thickens, as long as with the right amount Ethanol can be.
3, Tietu law
Electronic stores have sold a 'standard pre-cut symbols and tape, "pre-cut symbols common specifications D373 (0D-2.79, ID-0.79), D266 (0D-2.00, ID-0.80), D237 (OD-3.50, ID-1.50), such as several best buy paper-based material made (black), plastic base (red) materials do not try. Tape common specifications 0.3, 0.9, 1.8, 2.3, 3.7 and so are several. Units are in millimeters. According to the circuit design layout, the choice of the corresponding symbols and tape, paste it into the surface of the copper foil version. A little hammer with a soft, smooth as rubber, plastic, etc. beat chart stickers to make adequate adhesion with copper foil. Focus on percussion lines bend, lap. When cold, the best surface heating with heating allows to enhance the adhesion effect. Post good after the etching process can be carried out.
4, mimeographed law
The waxed paper on the plate, the circuit diagram of 1:1 pen engraved on the waxed paper, and put on wax paper circuit diagram engraved by board size cut, cut copper clad printed on waxed paper. Apply a small amount of paint and talcum powder into a thin thick appropriate printed material, with a brush dipped in printed materials, evenly onto waxed paper, repeated several times, the PCB can be printed circuits. This stereotype can be used repeatedly, suitable for small batch production. Tip: Using Optical transcripts printer can automatically size 1:1 stencil engraved made in accordance with the design drawings.
5, hot melt plastic film-plate method
This article was collected from the network (author NewBlue), feasibility untested, for reference.
① Circuit Board printer will print at a 1:1 ratio in 80 grams copy paper. You can also hand-drawn, but the end of the paper should be flat.
② to find a fax machine, fax paper inside the machine to remove and replace the hot-melt plastic film (reportedly can buy, who has the goods, please contact the webmaster). Schematic entry into the fax machine, the use of fax copy button to copy the wiring diagram on the hot-melt plastic film. Then the printed circuit board "printed originals" on the well.
③ paper with double-sided tape plastic film made a good map will be posted on the flat Bonded Copper. Note should be smooth, not wrinkled, paper tape does not cover melted part, or affect the production of the effect of circuit boards.
④ with a paint brush to paint brush evenly on the plastic film, Note: You can not brush back and forth, can only turn in one direction along the brush, otherwise wrinkled plastic film together on copper lines will overlap. Schematic were all to be brushed over, carefully remove the plastic film. Then on a printed circuit board printed better. After dry, you can corrode.
If you want to print pieces, do a little bigger than the wooden frame board, flat screen will be deposited in the wooden frame, fixed. Double-sided adhesive tape and then will be a good shadow plastic film attached to the screen below. The Bonded Copper on the table, close the wire rack (printed map and Bonded Copper To Justify), along with a paint brush to paint in one direction followed by a good brush, remove the grid. Printed circuit board printed on it. If defective, can modify the paint and bamboo.
The above procedure should be noted that when the painting, hand firmly to the severity of properly, too much paint is too thick, the line will run lace, too light lines will appear broken. Plastic must face up.
6, using the pre-coating of the photosensitive copper clad
The use of a dedicated CCL, its copper platinum layer on the surface coated with a layer of photosensitive material in advance, so called "pre-coated with photosensitive Bonded Copper", also called "photographic plate." Production as follows:
① single panel production: PCB computer-drawn map, use inkjet paper print out 1:1 720dpi black and white drawings (component side), if you use a laser printer can output drawings. Take a considerable size and drawings photosensitive plate, remove the protective film. Transparent glass or plastic plate with the drawings and the photosensitive PCB board pressed, exposure to the sun for 5-10 minutes. 1:20 with developing the drug with water distribution is developed, when exposed portions (unwanted deposited copper) completely bared, the rinse water can be etched with a ferric chloride. After the operation of skilled can be made out of alignment accuracy of 0.1mm!
② sided circuit board production: Step Reference single sided, double sided mainly positioned on both sides to be accurate. Can both sides were exposed, but the time to be consistent, while at the other side of the exposure of black paper to use protection.
From the principle of this method is the most simple and practical way, but commercially available "pre-coated photosensitive copper clad" price is relatively high, and difficult to buy. Therefore, this method is not recognized by most amateurs.
7, thermal transfer paper making method board process
Using a laser printer, the graphic design of PCB copper platinum printing to thermal transfer paper, thermal transfer paper and then close to the surface of the copper platinum CCL to the appropriate temperature heat transfer paper to print up the original Graphics (in fact, toner) will be heated to melt, and transferred to copper platinum surface, forming a corrosion protection layer. This method is much simpler than the conventional method of printing plate, and now most of the circuits are designed using computer CAD, laser printers are also quite popular, this technology is still relatively easy to implement.
Making a circuit board electronics enthusiasts almost every essential step in making things, while there are many methods of making circuit boards, such as the knife-plate engraving, thermal transfer method, wherein the cutter plate is the simplest lithography , one of the most efficient, but this board is suitable for relatively simple circuit board.
Knife engraved plate method, referred to as: Daoke Act
Pre-production preparations:
1, Bonded Copper
It is essential for the production of circuit boards thing, it is an epoxy resin insulating board or cardboard 1-2 mm in thickness and have a certain strength and facilitate the processing of the substrate material, and covered with a layer of 0.1 mm on the substrate copper foil around together, if only one side coated with copper, called single-sided copper-clad, if both sides have copper, called double-sided copper clad.
2, knife
Can be broken hacksaw piece, it can be relatively sharp knife or other things, the role of the board is making plans to open the Bonded Copper foil, constitute the circuit diagram.
3, drill, drill
Punch. Drill ships requires a 0.8-4mm, 0.8mm mainly for some small devices, such as resistors 1/16-1/4W.
4, sandpaper
Polishing. More than 300 heads of waterproof sandpaper, the smaller the particle, the better.
Production methods:
1, the control circuit board diagram, cut out a piece of the appropriate size Bonded Copper, the copper-clad side up, and then a carbon cap on top, then the board will draw a good view of the cap on carbon, then the ball-point pen on paper re-scan once, so the line is displayed on Bonded Copper.
2, with a knife gash in accordance with the circuit diagram a little bit, and to ensure real disconnect between the line and the line.
3, which is the basic circuit board prototype has been constituted, punch in the appropriate place, and then use sandpaper to polish the copper foil and then coated with a layer of water on the copper foil rosin alcohol, both to prevent oxidation and helps solder .
In addition to the six kinds of methods to collect
Method 1:
1 cut the copper-clad circuit diagram of a desired size.
2. Put wax paper on the plate, the circuit diagram of 1:1 pen engraved on the waxed paper, and put on wax paper circuit diagram engraved by board size cut, cut copper clad printed on waxed paper. Apply a small amount of paint and talcum powder into a thin thick appropriate printed material, with a brush dipped in printed materials, evenly onto waxed paper, repeated several times, the PCB can be printed circuits. This stereotype can be used repeatedly, suitable for small batch production.
3 to 1 g of potassium chlorate, the concentration ratio of 40 ml of 15% hydrochloric acid etching solution formulated into, and put it on the board where required corrosion corrosion.
4 would be good corrosion PCB repeatedly washed with water. Wipe off the paint with banana water, and then washed several times, so that the PCB clean, leaving no corrosive liquid. Add a layer of rosin solution to be dry holes.
Method 2:
Method of making printed circuit board in the amateur many conditions, but it is not time-consuming, is the "process" complex, or boast about quality. And I (Note author) method of making printing plates belong to the combined effect of a better one, as follows:
1. Printing plate system diagram. The figure represents the pads with a point, the connection can go one-way, but the location, size, need accurate.
According to the size of printed board plans tailored good printing plates, good clean copper surface.
3 with a carbon copy the chart to the printed board, if the line is relatively simple, and the producers have some system board experience, this step can be omitted.
4 depending on the kind of situation elements, pasting a standard pre-cut inner and outer symbol (pads); then, if the current size of the adhesive tape in lines of different widths. For standard notation and pre-cut tape, electronic stores. Pre-cut symbols common specifications D373 (0D-2.79, ID-0.79), D266 (0D-2.00, ID-0.80), D237 (OD-3.50, ID-1.50), such as several best buy paper-based materials do (black), plastic base (red) materials do not try. Tape common specifications 0.3, 0.9, 1.8, 2.3, 3.7 and so are several. Units are in millimeters.
5 little hammer with a soft, smooth as rubber, plastic, etc. beat chart stickers to make adequate adhesion with copper foil. Focus on percussion lines bend, lap. When cold, the best surface heating with heating allows to enhance the adhesion effect.
6 into ferric chloride corrosion, but should pay attention to, liquid temperature not higher than 40 degrees. Corrosion should be promptly removed after the rinse, especially with the case of thin lines.
7 drill, with fine sandpaper lit copper, coated with rosin alcohol solution, dry the production is completed. The quality of this is very close to the regular PCB PCB. Tapes can be between 0.3 mm IC feet across, can greatly reduce the front panel jumpers to short to save, save time. I use this method to experiment printing plate or a small amount of product at work often.
Method 3:
The paint flakes (ie shellac, chemical raw materials store sale) of a dissolved three anhydrous alcohol, and appropriately stirring, until all dissolved, a few drops of medical gentian violet (gentian violet), it presents a certain color, stir, can be used as a protective lacquer painted circuit boards.
First with fine sandpaper to polish the copper-clad, and then using the drawing pen drawing instruments (or compass used to draw graphics on the ink drawing pen), be depicted, adjust the nut on the stroke thickness duckbill pen stroke thickness adjustable, and can borrow ruler, triangle ruler depict a very fine line, and lines depict the smooth, uniform, no jagged edges, giving a smooth, fluent feeling; can also idle at the circuit board write Chinese characters, English, spelling or symbol
Depict the lines, if the surrounding infiltration, it is the concentration of small, can add a little paint flakes; If not drag open pen, it is too thick, you need a few drops of ethanol. In case description was wrong does not matter, as long as a stick (matchstick), make a small cotton swab dipped in a little ethanol, can be easily erased and then redrawn to. Once the circuit board illustrations, After, ferric chloride solution to corrosion. After the circuit board corrosion, paint is also very convenient, with a cotton ball dipped in ethanol, it can be erased to protect the paint, a little dry, you can use along with painted pine fragrance.
As the alcohol evaporates quickly, the prepared paint protection should be placed on the vial (eg inkwell) sealed after use, do not forget to cover the cap, if used in the next, found that the concentration thickens, as long as with the right amount Ethanol can be.
Method 4:
The sticky notes stuck to the copper-clad copper foil, and then paste the surface drawing good circuit, and then the knife carved through veneer layer, to form the desired circuit, thrown off the last part of the non-circuit current with ferric chloride corrosion or Electrolysis can produce an ideal circuit board.
Etching temperature may be about 55 ℃ etching speed. Corrosion good rinse with water boards, thrown off sticky notes on the circuit, lay hole clean painted rosin alcohol solution ready for use.
Method 5:
1 The size of the circuit diagram of the components used in the area of the shape and the position of the printing plate and the density of each component element reasonable arrangements. Determining element position should be in accordance big small, the first overall after partial principles, the adjacent circuit elements placed nearby, neat uniform.
2 wire connection between the various elements in the corner and the two lines intersect at a right angle turn is not required to use the transition curve can not cross each other and detour too far. Some conductors really can not do this, you can consider the opposite of the printed board printed wire, then nailing the front circuit connection, or otherwise connected with insulated wire welding components.
3. Input and output portions of some distance as well, so as not to interfere with each other.
Method 6:
Radio enthusiasts have to worry about making the board too. Now to introduce a kind of "Asian print" law making printed circuit boards. Follows:
A, a circuit board in the printer will print at a 1:1 ratio in Figure 80 grams in the copy sheet. You can also hand-drawn, but the end of the paper should be flat.
B, find a fax machine, fax paper inside the machine to remove and replace the hot-melt plastic film (the company has sold). Schematic entry into the fax machine, the use of fax copy button to copy the wiring diagram on the hot-melt plastic film. Then the printed circuit board "printed originals" on the well.
C, using double-sided adhesive tape plastic film made a good map will be posted on the flat Bonded Copper. Note should be smooth, not wrinkled, paper tape does not cover melted part, or affect the production of the effect of circuit boards.
D, with a paint brush to paint brush evenly on plastic film, Note: You can not brush back and forth, can only turn in one direction along the brush, otherwise wrinkled plastic film together on copper lines will overlap. Schematic were all to be brushed over, carefully remove the plastic film. Then on a printed circuit board printed better. After dry, you can corrode.
If you want to print pieces, do a little bigger than the circuit board wooden frame, the screen (the company has a mesh sell) formation deposited in the wooden frame, fixed. Double-sided adhesive tape and then will be a good shadow plastic film attached to the screen below. The Bonded Copper on the table, close the wire rack (printed map and Bonded Copper To Justify), along with a paint brush to paint in one direction followed by a good brush, remove the grid. Printed circuit board printed on it. If defective, can modify the paint and bamboo.
The above procedure should be noted that when the painting, hand firmly to the severity of properly, too much paint is too thick, the line will run lace, too light lines will appear broken. Plastic must face up.
The method is also printed with the parts diagram as above.
Sensitive circuit boards
Scope: You personally produced experimental (small quantities) circuit boards.
Features: fast, economical, secure, high-quality,
Completely replaced by a simple universal mill plates and proofing expensive line.
Fine degree: The most thin up to 0.1mm, very complex circuit can successfully produced.
Production process: print (transparent film paper, parchment paper, 70g copy paper),
Exposure (sunlight, fluorescent, special exposure machine),
Development (dedicated developer), etching (ferric chloride), drilling (small drill)
Characteristics of photographic plates: high quality
Suitable for: Production Pilot (small quantities) circuit boards;
Alternative: A simple universal mill plates and proofing expensive line;
The most thin: 0.1mm (4mil);
Features: PCB schematics computer files with exactly the same;
Pros: Fast (1-2 hours), the economy, privacy, quality, personally produced.
Sensitive circuit boards for use
(1) Original production: the good circuit design schematic design software, and then use the printer for transparencies, translucent parchment paper to print out the base map; choose Mirror Print (graphics software has mirroring Mirror printing function) when you print the document, printed circuit diagrams ink (toner) surface must be in contact with the surface of the green photosensitive film closely in order to get the highest resolution; line portion, if any, translucent holes, please oily black pen repair; draft surfaces need to be kept clean and free of dirt.
(2) Crop: cut off the first with a paper knife-mediated protective film, and then saw or cutter cut the desired size of the board is good, poor adhesion is required to prevent Cuodao the circuit board edges polished. Electricity boards can also be used a knife to cut the upper and lower sides of the depth of about 0.2mm marks, and then be broken.
(3) Exposure: Remove the protective film (not to scratch the surface of the photosensitive film), a transparent or translucent originals placed on the plate, the glass and the plate is pressed against the document, the resolution, the better the more closely. Distance and time of exposure varies with different lighting changes:
1) Fluorescent: the distance between the lamps is 5CM, transparent draft standard time is 8 minutes ± 2 minutes translucent draft standard time is 10 minutes. If the width of the plate than 10CM, required two fluorescent light or using district average exposure, exposure time increased by 20%.
2) Sunlight: Time in strong sunlight 1.5 minutes to 3 minutes under low light.
3) the production of double-sided, you must add 2-3 positioning holes on the original, according to this position in the photographic plate drilling, so that the original alignment of the front and back and on the plate holes and fixed with double-sided adhesive tape is good exposure .
4) Self-coming production date six months for each additional six months, the exposure time is increased by 10-15%
(4) Imaging: the imaging agent used plastic pots watered by 5 g 300 - 500ML proportion of diluted developing solution (use cold water) poured into a container reserve; photographic plate face down on the exposed film into developing solution, the vessel rocked every few seconds, and no longer appeared so clear copper with a green mist emerging imaging is completed; soaked in the water for 2 minutes; dried with a hair dryer or; temperature of the water when imaging 15 to 30 degrees as well, pay attention not to allow imaging of pelvic floor damage dual-panel membrane surface; developing solution after use do not sink back into the container.
(5) repair membrane: To ensure no damage to the membrane surface, the dry photographic plates to conduct a comprehensive inspection, if a short circuit at the scrape with a knife, break point pen with oily patches.
(6) Etching: plastic pots with a 1:2 ferric chloride etching solution formulated water (temperature of 40 to 50 degrees is better), the photosensitive sheet into the etching is completed 10 to 20 minutes.
1) After-plate etching solution for about 20 seconds then let's put up the view, the nonlinear part of the copper foil should be pink, bright green, if that is not enough for the imaging, and then washed with water to its imaging time, but Be careful not to over-(appropriate to reduce development time).
2) Be careful not to damage the membrane surface etching to corrosion off the line.
3) Use only the photographic plate acidic etching solution, you can not use an alkaline etching solution.
4) the more concentrated ferric chloride etchant slower, more dilute too slow.
(7) In addition to film: photographic film can be welded directly (to use high-quality solder), for removal of the available imaging solution or cloth dipped in alcohol wipe doctrinal, after removing the film with rosin solution (200 ml of pure alcohol incense hondurensis 5 g dubbed) painted again polished good board, either flux, and can prevent oxidation.
