Radio amateurs often have to repair products powered by electricity. This imposes a number of restrictions on the use of adhesives: you have to use only conductive glue, otherwise the functionality of the part will be impaired. It is these tools that are used in the repair of microcircuits, keyboards, consoles, for sealing contacts in household appliances. Conductive glue is also useful for car enthusiasts in order to seal the wires and for many other purposes.
- Features and properties of conductive adhesives
- Differences in conductive compositions
- Do it yourself
- Graphite based
- Silver base
- Aluminum glue
- Shop glue
- The specifics of using homemade glue
Features and properties of conductive adhesives
For the first time, electrically conductive glue was made in Germany in 1940. Later it began to be actively used in various fields of mechanical engineering, and now it is generally considered a universal tool. This conductive glue can be used instead of soldering, for the arrangement of underfloor heating, heating systems: it withstands high temperatures. Other properties of the tool are as follows:
- fast drying speed, the need for work without pauses;
- high viscosity (eliminates leakage of glue into the electrical circuit);
- excellent adhesion to surfaces;
- safety for the environment and the user;
- elasticity (allows for spot application).
The main property of the glue is its low electrical resistance. The use of electrically conductive glue helps to give parts resistance to damage, shock, vibration. Also, the composition will protect the microcircuit from temperature extremes.
It is important that the adhesive for electronics does not have water in the composition. The water base will only ruin the electrical circuits, the contacts of the wires, and the tool itself will dry for too long. Typically, nickel or graphite powder, silver, or any other metallic, conductive current is included.
Scopes of conducting glues are various:
- repair of loops, computer boards, gadgets;
- installation of heating skirting boards;
- laying of antistatic linoleum;
- elimination of defects in electrics in cars, application for repairing rear window heating, heating threads;
- LED soldering replacement.
Differences in conductive compositions
There are a number of parameters by which conductive adhesives differ from ordinary ones. The main difference is that they include special substances with excellent electrical conductivity. It is thanks to them that the composition acquires the necessary qualities. Also the difference is as follows:
- weak strength against mechanical damage;
- specificity of the area of use;
- mandatory presence of a metal base;
- significant cost.
Do it yourself
Electronics repair technicians have to use large quantities of conductive adhesives. Therefore, due to the high cost, many are trying to make at home an analogue of store glue. A homemade product will serve no worse than the purchased one, but it is important to strictly observe the proportions when creating it.
Graphite based
The easiest way to do it yourself is to make adhesive from graphite. For this, graphite powder itself and nail polish (glue) are used.First you need to buy all the necessary ingredients: the cheapest transparent varnish or liquid or paste for gluing false nails is suitable. The glue manufacturing procedure is as follows:
- carefully unwind the foil on the glue on the back of the tube (if glue was bought, not varnish);
- take a simple pencil, remove the stylus;
- grind the lead to a state of fine powder;
- to connect with varnish or glue directly in a tube or bottle;
- mix the finished product with a toothpick;
- tighten the foil again, fasten the tube from below with pliers.
Unfortunately, such a tool can dry out when the tube is loosened, so air must be excluded. Colored varnishes will not work, because they have paint that can violate the conductive properties of the glue. But the unsuccessfully applied product is easily removed with acetone, nail polish remover.
to contents ↑Instead of a pencil, you can take graphite yourself from unnecessary copper-graphite brushes, salt batteries. It is possible to turn graphite into a powder mass with the help of sandpaper, needle file. After grinding the coal rod of the battery or brushes, the powder is mixed equally with zaponlak, achieving a creamy mass. By the way, the use of brushes will be an order of magnitude more effective, because the addition of copper seriously increases the conductivity.
Silver base
Glues on silver are much more difficult to manufacture than on graphite. However, wizards also often make such tools if they have all the necessary components. To work, you will need:
- formalin 1%;
- silver nitrate;
- ammonia (ammonia).
It is necessary to measure equal shares of silver and formalin, connect them together. In this mass you need to add just a couple of drops of ammonia. After a few minutes, a precipitate will appear at the bottom of the dishes - silver powder. To get it, you need to filter the liquid. Next, the powder must be dried at + 120 ... + 150 degrees. It is introduced into any transparent glue or varnish, as in the previous recipe. Before connecting the components, a little alcohol is added to the glue to dilute it.
There are other recipes for the preparation of a conductive composition that include graphite and silver together:
- Take 130 g of finished silver powder, 12 g of graphite powder. Connect them together, then add 8 g of nitrocellulose, 50 g of acetone, 3 g of rosin. Too thick a mass can still be diluted with acetone. After mixing, the agent can be immediately used as a conductive composition, but it practically does not stick together the parts (usually it is applied as an electrically conductive primer).
- Combine 30 g of graphite, 70 g of silver powder. Pour 70 ml of acetone, 60 g of vinyl acetate. With thorough mixing, a syrup with conductive properties is obtained. It can be used as a coating for other adhesives, for example, BF.
Aluminum glue
This metal also has excellent conductive characteristics. Epoxy resin is usually used for the binder component. Since it quickly enters the polymerization reaction when hardener is added, it is necessary to introduce aluminum into the resin before mixing it with a liquid substance. It is necessary to take aluminum powder, mix with resin until a mass with the consistency of sour cream is obtained. It must be given uniformity, measure the right amount and combine with the hardener in a proportion of 1:10.
Shop glue
Conductive adhesives are sold in construction, hardware stores. Many order funds from Aliexpress, other online stores. Despite the good quality of homemade adhesives, their strength is poor. In addition, when using low-quality components, there is a risk of spoiling the equipment. Therefore, you can consider buying glues.The most popular are Kontaktol brand products from the German Keller concern:
- "Contact" is a single component. Designed to organize or restore conductive bonds on dielectrics - glass, polymers, textolite and other materials. It includes silver, synthetic resins, is very resistant to moisture, and has high adhesion.
- "Contact Radio". Made on graphite powder. It has similar properties, but its price is 2 times cheaper.
- "Contactol conductive marker." Also contains silver powder, palladium, polyvinyl chloride resins. The convenient form helps to glue even hard-to-reach areas. Most often, the tool is used to repair jumpers, electrically conductive paths.
Another good glue is Mastix. It includes nickel powder, is used to restore the heated rear window of a car, it is considered the best in its segment. Glue Done Deal is a polymer-silver composition, it is also used to repair threads and contacts of cars made in the USA. The product has a very high quality, excellent adhesion.
Other good adhesives:
- Glue for Permatex heating contacts (Permatex). It is resistant to vibration, ultraviolet, temperature difference.
- Clay Abro Masters. Also designed for repairing rear window heating threads, manufactured in the USA.
- Eurocol Forbo 523. This is a dispersive conductive adhesive, used for gluing linoleum, carpet. Frost-resistant, solvent-free, odorless.
- Liquid silver Baku BK 426. This conductive paste is used to restore the tracks on the boards.
- Glue Astrohim (Astrochem) conductive. Designed for repair of glass heating threads.
- Irpol elastic adhesive 5. Based on polyurethane binders. It is used for arranging antistatic coatings.
The specifics of using homemade glue
When it comes to repairing expensive equipment, experienced craftsmen recommend not saving and apply only purchased glue. The latter has the best technical characteristics and is ideal for specific cases. In other situations, you can take home-made glue, because you can seriously save on its manufacture. Problems can arise only with the storage of funds, because it is worth making small portions of glue that will be used immediately.
