Epoxy Resin Grinding

Polishing epoxy products

Many needlewomen make jewelry from epoxy compound now. “Home jewelers” know for sure that when the product is taken out of the mold (mold), a groove is often formed on the casting side. It turns out that as it hardens, the epoxy decreases slightly in size and changes shape. No less often there is a need to correct smooth crystals, pendants, medallions. On their back, streaks, streaks, and build-ups may appear. Also, there is a need for surface treatment in the presence of such defects:

• surplus of the filling compound;
• scratches and small chips;
• protruding edges;
• uneven, pointed edges;
• depressions.

If the defect is serious, there is no need to despair. You will have to thoroughly polish the object, and then apply another layer of epoxy. This will hide the flaw without sacrificing quality. All cons will be smoothed out, the product will look perfect. Grinding and polishing is the final stage of the work that completes the decoration.

Reasons for the appearance of defects after painting

There are several main reasons for which certain shortcomings appear after painting a car.

Dusty room

Among all the defects in the paintwork, the adhesion of debris during operation occurs in 70% of cases. The reason for this: dust in the garage, poorly washed car, insufficient ventilation of the room. The paint defect is eliminated by "wet" or "dry" grinding. Sandpaper with a degree of abrasiveness of at least 2000 grit is used if sanding is done by hand. You can use a sander. Polishing the sanded surface is required.

Shagreen

The reason for the appearance of "orange skin" on the body, instead of a beautiful shiny surface, is simple:

1. Using too thick varnish or paint. Often a defect occurs due to the driver's carelessness, each paintwork has an individual application technology, number of layers, and dilution parameters.
2. Wrong choice of spray gun for painting. At low air pressure in the nozzle of the gun, the paint is sprayed on the surface of the body unevenly, the density and thickness of the coating cannot be maintained.

Matte

The defect of the matte surface instead of gloss will be noticeable only on the fifth day after painting. If you moisten the body with water, it will shine in the sun, showing the color that the driver would like to see on his car at all times. A defect appears if:

1. High room humidity with no ventilation at all. If painting is done in winter, the garage should be well warmed up, the temperature should not fluctuate, dropping below 15 degrees and not rising more than 25.
2. High pressure in the nozzle of the gun if painting is done with a spray gun (not a production paint can).
3. Incorrectly selected thinner with high cooling performance and low drying class.

Breakthrough air droplets

The defect appears a few days after painting. Causes:

• Unsuitable brand of thinner that evaporates quickly;
• Application of thick layers of paint;
• Painting with the second or third layer occurs on the insufficiently dried first layer;
• High drying temperature or using a hot fan.

GOI paste: what is the green mass?

The name stands for State Optical Institute. It was there that this cleaning material was created in the 30s. last century. It looks like a greenish mass, sold in the form of a smooth bar and in a sealed jar.

Cleaning agent composition

The main component in the composition is chromium oxide.The granularity of the preparation and characteristics directly depend on its concentration. The higher the percentage of chromium oxide, the coarser the composition (the variation can be from 60 to 85%).

Varieties of pasta differ in their graininess. Each of them is given a special number:

• No. 4 is rough. It contains: chromium oxide - 81%, stearin - 10, fat - 5, kerosene - 2, silica gel - 2. Light green tint, best of all combes off the top layer of the material. Removes large scratches left by other abrasives.
• No. 3 - medium. Chromium oxide - 76 part, fats - 10, stearin - 10, kerosene - 10, silica gel - 2. Pure green shade. Removes minor irregularities and scratches, gives the material a matte finish.
• No. 2 is thin. Chromium oxide - 74 parts, stearin - 10, fat - 10, oleic acid - 2.8, kerosene - 2, silica gel - 1, baking soda - 0.2. This composition is characterized by a dark green color. Used to polish most items.
• No. 1 - thin. Nitric oxide - 65-70%, stearin - 10, fat - 10, kerosene - 10, silica gel - 1.8, soda - 0.2. Differs in dark color with green tint. Goi pastes 1 and 2 are designed for lapping or finishing the material and give it a shine and shine.

The dried green mixture can be "reanimated" so that it becomes soft again. This is done with machine oil. On a small piece, ground into small crumbs, drop 3-4 drops of machine oil or any other technical oil. Place in the microwave for 30 seconds and grind the ingredients into a homogeneous mass.

Grinding recommendations

In order not to have to remove too large defects, you should take preventive measures in advance, work carefully, carefully. Molds are poured slowly, without sudden movements, evenly

This will reduce the risk of groove formation. The table for work must be set horizontally on a level, then the epoxy will be distributed without drips, distortions.

To achieve a shiny surface of the product, you should choose molds with glossy walls. The matte base of the molds will give the same "look" to the epoxy decorations.

Below is the order of polishing work, if defects on the products are still formed:

1. After shaking the jewelry out of the mold, you need to carefully examine it. If there are large defects, rough processing is required first. It is ideal to use a polishing machine with a speed of up to 1000 rpm. This method will eliminate waves, build-ups, and make the product smoother.
2. The second step is to add transparency to the decoration. To do this, the object must be polished with a smaller abrasive. Professional wheels with fine grain are used, as well as special car polishing pastes. The circle is smeared with paste, first make sure that it is dry, clean, without scratches.
3. After using the polish, you can get a transparent, even surface of the hardened resin. Even the smallest flaws will be eliminated.
4. At the end of the work, it is recommended to cover the product with a special varnish that protects the pigments from UV radiation. This is also required to prevent yellowing.

Some authors advise polishing epoxy objects with foam rubber wheels set on a drill, including small turns. First, they are passed along the edges with fine-grained sandpaper with water, removing large irregularities. Then the decoration is brought to shine with foam rubber and polishing paste. If there is no polish, use soapy water. Felt tips should not be used as they can damage the epoxy object.

How to polish jewelry and other products if there are no special tools? You can take a regular manicure set. They cut down irregularities, then polish the surface to the end with sandpaper by hand with water (use a grain of 600-800). At the end of the work, take a polish, rub it into the object with a cotton mug. The base becomes completely transparent. After using parquet varnish on water base, which will give the decoration a complete look. Instead of this material, it is permissible to apply a gel polish coating, then dry it with a special nail lamp.

Plastic grinding

Grinding of plastic is used when it is necessary to remove deep damage that cannot be sufficiently smoothed out in other ways. Plastic is easy to sand due to its relatively low melting point. In the case of measured and accurate work, the result will be a uniform matte plane in place of deep grooves. To grind plastic, follow the following work algorithm:

1. Clears the workspace of those tools and items that will not be needed when sanding plastic.
2. Several emery sheets of various grain sizes are prepared.
3. The operability of the grinding machine is checked when this tool is not present; it is possible to enhance the grinding effect with the help of a soap solution.
4. The plastic object previously degreased with acetone is placed on the work table.

Attention!

Grinding is a leisurely undertaking that requires the accuracy and precision of every step.

In the process, the temperature is monitored, since overheating is contraindicated for the material. Gradually they pass from coarse-grained to fine-grained skins. After processing with each piece of sandpaper, wipe the treated area with a dry cloth, this will avoid flaws and prevent the omission of flaws - plastic shavings sometimes hide a missed scratch.

Sanding plastic from deep scratches

Deep scratches are difficult to repair with putty, as burrs and the elasticity of the grout itself interfere with this. In addition, it is not always possible to select the material of the desired color, which will not be visible after hardening. It should be borne in mind that polymer plastic is soft and easy to grind. The main condition is to maintain a low surface temperature of the product during the restoration process. From strong friction with a high range of motion, the synthetic mass is heated and melted.

To work, you will need the following tools and equipment:

• sandpaper of different grain sizes;
• grater for handmade;
• grinder of any principle of operation;
• soft brush;
• soap;
• rags.

It is recommended to grind the plastic according to the following method:

1. Secure the product to a solid and stable base. You can use vices, clamps and self-tapping screws.
2. Attach the coarsest emery paper to a hand or power tool.
3. Moisten the surface to be treated with soapy water. This will reduce friction and prevent it from overheating.
4. Apply gentle pressure in a circular motion to treat the damaged area, taking 1-2 cm of a clean area.
5. Change the nozzles as the polymer grinds down, gradually reducing the grain size. Perform the final stage with zero.
6. Wash off the liquid, check the quality of the work performed. Repeat the procedure if necessary.

The result should be a flat matte surface with a uniform texture. After that, the material is brought to the desired state with more delicate means.

Surface preparation

In the manufacture of epoxy products, smudges and sagging of resin often occur, and other defects are revealed during inspection:

• Excess flowed out of the contour during filling;
• Whitish spots caused by the ingress of water vapor;
• Small chips, scuffs;
• Folds, shrinkage depressions;
• Uneven edges, too sharp edges.

All these defects are repaired with harsh abrasive materials prior to grinding. Correctly sanded resin looks inconspicuous, epoxy turns out to be matte, this is normal.

Correctly sanded resin looks inconspicuous, epoxy turns out to be matte.

Before starting to polish the epoxy, it is necessary to dust the surface and degrease the surface (remove traces of hands, grinding paste).Without preliminary preparation, it will not be possible to thoroughly polish the resin to a mirror finish.

A few recommendations:

When pouring an epoxy layer, it is important to pay great attention to the formation of the edges;
If water gets into the resin, polishing cannot achieve perfect transparency, milk traces will remain;
Epoxy is applied in several stages, allowing the previous layer to polymerize. Then the shrinkage of the material will be uniform, no cracks, dips, waviness will appear;
Before processing, all surfaces are subjected to a test edge turning.

Before starting to polish the epoxy, it is necessary to dust the surface and degrease the surface.

Before starting to polish the epoxy, it is necessary to dust the surface and degrease the surface.

Carrying out polishing work after painting

If your car is just after painting, there are some nuances as to how to properly polish the car. This must be done, since even very high-quality staining leaves noticeable traces behind. It is by polishing that you can get rid of them, bringing the state of the body to the desired perfection. First, preparatory work is carried out, which consists of:

• thorough washing of the vehicle;
• pasting with tape areas that will not be treated with polish;
• blowing with compressed air;
• degreasing surfaces.

Sanding can be done wet and dry. Wet polishing involves periodically wetting the sandpaper in water. This technique is suitable for those who perform manual processing. This method is not suitable when working with a typewriter. Step by step wet processing is as follows:

• the surface is treated with clean water;
• sandpaper with a grain size of about 1200-1500 is wound on a plastic spatula;
• gradually wetting the body with water from a sprayer, sanding is carried out;
• all irregularities are removed with paper;
• the paper changes to a finer-grained one about 2000-2500;
• using a protective paste and a sander, process the entire body.

When the job is done, be sure to wash the car using a quality car shampoo. This will remove any residual paste, and also permanently set the result.

Surface care

Features of epoxy resin - low heat resistance. Do not put anything hot on the table, use aggressive detergents containing acids and alkalis for washing. From chemical attack, the resinous layer can become cloudy.

Do not put anything hot on the table, use aggressive detergents for washing.

Epoxy has taken its well-deserved place on construction sites, in everyday life due to its universal consumer properties, translucency, and low shrinkage coefficient. A synthetic oligomer, consisting of a hardener and a base, forms a waterproof film comparable to many building materials.

Pros and cons of polishing

Any product (Colgate pastes are often used for polishing) contains soft abrasive particles designed to remove plaque. Processing the glass cover will not reduce scratches more than 3 mm deep, and it will not be possible to grind the chips.

Polishing the plastic headlights is more effective. Soft plastic, after being hit by gravel, is covered with a fine web of shallow cracks, which are easier to polish with a soft abrasive. Among the advantages of this method are the following:

• the ability to carry out work anywhere on your own;
• cost - the price of a tube of paste;
• small amount of time (from 30 minutes).

The disadvantage of this method is the lack of a long-term effect. Polishing with toothpaste will only brighten the headlamp for a few months. Cosmetic resurfacing will have to be done all the time.

Grinding and polishing process

For the initial stage, it is recommended to use a tape nozzle that covers a large area. For finishing jewelry and countertops, it is better to use eccentric of various sizes.

When using a drill, it is important to correctly adjust the rotational speed of the nozzle so that no overburden occurs.

If there are large defects, they are eliminated by rough processing. Recommended rotation speed - up to 1000 rpm, initial abrasive grain size - 80. When waves, sagging and other irregularities are eliminated, proceed with further grinding. The coarseness is gradually reduced: 80 is replaced by 100, then the next increase is made until the 2000 marking is reached.

For finishing jewelry and countertops, it is better to use eccentric of various sizes.

It is undesirable to use felt, it creates scratches. Grinding and polishing pastes are rubbed with a soft cloth. For better sliding, add solid oil or petroleum jelly. The resulting oily film can be easily removed with water. The epoxy is polished to a lasting shine.

Polishing compounds eliminate even slight roughness on the surface of the resin, the layer becomes transparent and takes on a noble appearance. It is necessary to strive to eliminate all defects, then you will get a high-quality countertop or jewelry. Using professional tools, fine-grained pastes, it is possible to avoid scratches and dullness.

It is necessary to strive to eliminate all defects, then you will get a high-quality countertop or jewelry.

After finishing the product with colored resinous compounds, it is recommended to cover it with a special varnish that protects the pigments from UV radiation. Colorless epoxy layers after such an operation will not turn yellow, the color of the base to be poured will not be distorted.

Some masters recommend using soapy water after finishing. In a solution of dishwashing detergent, a fine-grain polishing nozzle is moistened, and the tool is passed over the entire surface. All the shortcomings that could not be eliminated immediately become visible. Soap is also used as a polish for fine jewelry finishing.

After finishing the product with colored resinous compounds, it is recommended to cover it with a special varnish.

Why polish cars

First you need to understand the functions of polishing the car body, since not everyone understands why such events are required. For some reason, some are sure that it is enough to wash the car with water and shampoo, wipe it with dry rags and that's it, it's done. But do not forget about the last stage, which is precisely the use of polish for the car body. There are 2 main functions for which polishing is performed:

• Small damages, defects and scratches on the paintwork are eliminated. The polish can remove irregularities, chips and scratches. We are not talking about major damage, since only painting can cope with it. But the polish helps against minor defects very effectively;
• The most attractive appearance is created. For clarity, you can simply put two identical machines next to each other, one of which is simply washed with water, and the other is polished. The difference will be significant. It is for the sake of this gloss that many motorists are ready to spend 1-2 hours processing the body.

Often, restorative treatment is carried out in car services, where work is performed on painting and straightening the body. But there are those who are ready to do everything with their own hands. If you plan to contact specialists, please note that the cost of the service depends on a number of factors. Namely:

• car service level and status;
• region;
• the type and size of the vehicle;
• body condition;
• features of the paintwork;
• the severity of the damage;
• type of polish used, etc.

Speaking about prices in the capital, the estimated cost will be from 4 thousand rubles for handling a small car with minor damage. If you have an SUV and there are more serious defects on its body that require high-quality restoration polishing, you will have to pay at least 10 thousand rubles.

Important safety instructions

Remember that epoxy glue becomes completely safe for humans only after the complete polymerization process. This requires 1.5–2 days. When working with a liquid resinous substance, it is necessary to use personal protective equipment: a respirator mask, gloves and goggles. Such protective measures will also be needed during the subsequent (finishing) processing of finished products.

Do not allow the inhalation of small particles of abrasive, such dust is very harmful. And after the end of the work, the room should be thoroughly ventilated, the clothes should be sent to the wash, and all working tools should be rinsed. The place where the polishing work was carried out is preliminarily covered with a plastic wrap, which after finishing the work can be thrown out or thoroughly wiped with a damp cloth.

Home polish

Before you polish the car yourself, you should choose the right tool that will be able to cope with the task at hand. Therefore, polishing is divided into protective and abrasive. In the first case, polishes are used that are designed to process the body without large chips and scratches. The purpose of the product is to give the surface a shine. Even a novice motorist can handle this. The second category is abrasive. It is used when working with scratches, abrasions and chips that can no longer be removed with ordinary protective polish. The process becomes more complex and time consuming. To do everything correctly, you need to study a number of key tips and be extremely careful. If you do not need serious polishing of the car body from scratches, and want to do everything yourself, buy high-quality protective compounds. They are sold in any automotive chemistry store and are non-abrasive. Carefully study the components from which the protective polish is made. There are several of the most effective and relevant solutions:

• Wax. The cheapest protective polishes are made on the basis of wax. You should not expect the highest quality from them. Withstands up to 3-4 washes, after which you need to re-process the car;
• Teflon. They are able to maintain their properties up to 8 washes without additional processing. For the manufacture of the product, synthetic polymers are used, which makes it possible to create an effective water-repellent coating. Teflon compounds provide the best gloss, depth and brightness to the body color. Additionally, Teflon protects against corrosion and minimizes the negative effect of ultraviolet radiation on the paint layer;
• Epoxy. Quite expensive formulations that are not very easy to work with. But if you are willing to spend money and time, the result will exceed your expectations. Formulated with epoxy resins to protect against dust, water and dirt. Copes well with aggressive environments, preventing them from destroying the paintwork;
• Preservative varnishes. It is worth using these compounds only when the machine has to be operated in difficult conditions. They perfectly repel water, protect against mechanical and chemical influences. High-quality preservative varnish stays on the body surface for up to 2 years.

These polishing compounds are applied by hand without using a sander. It is enough to take a good lint-free cloth and rub all body elements thoroughly. But be sure to wash the car before use to get rid of dirt and dust.If you have a sander at your disposal, you can use a soft wheel to apply a protective polish. Polishing compounds have different components. Basically, motorists use products with the addition of:

• boron;
• wax;
• diamond;
• teflon;
• paraffin;
• liquid glass.

Each product has its own characteristics, composition, degree of abrasiveness and purpose. They should be used according to the manufacturer's instructions. For abrasive processing, pastes are used, which contain special abrasives. Such polishing is more difficult, since it consists of a larger number of stages, including sanding. Only after that, the surfaces are sanded with abrasive pastes, wiped, dried, and then a protective polish is applied.

Polishing rules for epoxy resin products

Epoxy polishing is especially required for correcting smooth products: medallions, pendants, crystals. This procedure also helps to remove excess resinous mass, small chips and scratches. Competent polishing helps to cope even with serious defects.

Once cured, the epoxy requires polishing

Knowing how to polish epoxy resin to a transparent state, you can bring the finished product to perfect condition by removing defects such as:

• the remaining particles of hardened resin;
• small chips, scratches, scuffs;
• irregularities in the form of pointed corners and edges;
• depressions and potholes.

Necessary tools for DIY sanding

Before figuring out how to polish your epoxy, you need to prepare all the necessary accessories. Epoxy can be polished in various ways. This operation is carried out both manually and using special tools. The most accessible of the polishing mechanisms are:

• familiar nail file for manicure;
• fine-grained sandpaper;
• trowel sponge.

Hand grinding of epoxy is only applicable to delicate and exquisite items, delicate jewelry. Large and more massive objects are first treated with coarse abrasive sandpaper, then gradually lower the grain size, bringing the object to a perfectly even state. Also, other tools will be required to polish the resin:

1. Dremel. Special tool with various attachments. When rotating, it perfectly grinds objects. It is often used by jewelers to process jewelry.
2. Fraser. And this tool is well known to manicurists. In its work, it is identical to the dremel, but when rotating it makes fewer revolutions.

Useful polishing tips

Knowing how to polish epoxy at home, you can achieve a perfectly flat surface of your products. To do this, adhere to the following finishing instructions:

1. Take the product out of the mold and inspect it carefully.
2. In the presence of major defects, the item is preliminarily subjected to rough processing. It is better to use a polishing machine for this.
3. A coarse initial polish will remove build-ups and unevenness for a smooth finish.
4. Making the subject matter transparent. Fine-grained nozzles are used for polishing. Polishing paste will also be of great help (you can use a paste designed for cars). It is applied to the polishing wheel.
5. The polish will give the item the required transparency and a smooth surface. After these manipulations, the product is covered with a protective varnish that protects the item from UV radiation. This method will protect the epoxy from further yellowing. Use a specialized parquet varnish, and when processing small products, a manicure gel varnish is also suitable (it dries out under a special lamp).

Various options are suitable for polishing

How to minimize the occurrence of defects

Of course, it is better to avoid defects at the stage of pouring the resinous substance into the molds.The molds are poured very carefully and slowly so that the resin penetrates into all the recesses and completely fills them. And to achieve an initially smooth surface - use forms with a glossy surface. The matt structure will give the matte finish to future products. To significantly reduce the likelihood of defects, the mold is poured only on a strictly horizontal surface.

Preparing for the process

Before starting work, you need to inspect the object in order to identify the degree and nature of its damage. This is necessary in order to choose the optimal repair method to achieve the desired effect.

In order to get rid of external defects, you can use one of the following methods:

1. Thermal. It consists in the thermal effect on the material, as a result of which it loses its hardness and becomes viscous.
2. Mechanical. To polish the plastic from scratches at home, abrasives are used to grind down irregularities.
3. Chemical. Substances are used that change the structure of the plastic or fill all cavities on its surface. After the end of the action of the drugs, the surface becomes one with them.

After choosing a repair method, prepare the workplace and the damaged object. It should be restored on a table covered with oilcloth or cellophane. The product itself is cleaned of dirt and washed. It is best to use dish soap and a soft brush for this. After the surface is cleaned, it must be wiped dry with a natural cloth. If the polymer is enclosed in a metal or wooden frame, then it must be covered with mounting tape to prevent deterioration by reagent or abrasive.

Required tools and materials

Surfaces made of high quality epoxy compounds acquire a marketable appearance after preliminary grinding and final polishing. The technology is very different from the process of processing glass, stone, plastic.

Jewelry is mostly hand-conditioned using:

• Diamond nail file;
• Fine-grained sandpaper from "three" to "00";
• Foam rubber or special trowelling sponges with a glued layer of abrasive of various grain sizes;
• Polishes, various polishing compounds or GOI paste.

Surfaces made of high quality epoxy compounds acquire a marketable appearance after preliminary grinding and final polishing.

The manual method is used in the manufacture of delicate products with a fine finish. It is inconvenient to handle tables in this way. Grinding large areas by hand is too tedious and time-consuming.

To speed up the process, tools are used:

• Dremel is a kind of drill with a rotating rod, on which all kinds of grinding attachments are attached (minus the use of a dremel - the speed of the attachment is too high, beginners can damage the surface to be treated with a careless movement);
• The drill is used to cut large beads, beads, formed during the restoration of damaged epoxy coatings ”;
• Mobile nail cutter - a tool similar to the dremel, but with a lower speed, used when performing delicate work, the diameter of the disc nozzles varies from 10 to 100 mm.

Grinding large areas by hand is too tedious and time-consuming.

Features of consumables:

• The grain content of the nozzles is gradually reduced, the smaller the grain size, the smoother the epoxy layer is polished;
• GOI paste is chosen by color: coarse light green, medium - gray, small - brown (the smallest is almost black), only green and gray are used for grinding;
• Automotive polishing paste 5041-3M, sold by weight, is cleaner than GOI paste, smoother on the attachments;
• The polishing wax for finishing removes too thin a layer, the polishing process is delayed;
• A good result is given by polishing pastes produced under the MIRKA brand, creating a mirror shine (Polarshine 35 is a grinding product, it creates a uniform matte, Polarshine 20 paste is used for finishing).

Polishes containing silicone quickly create a pleasant shine, but the effect is short-lived.

Tools and materials

Epoxy jewelry is processed manually or mechanically.

For the manual method, take the usual tools in the form of a nail file, sandpaper and a trowel. This method is suitable for fine jewelry work, when making delicate jewelry. It is also advisable to have a magnifying glass or lens - their use will allow you to do the job flawlessly.

For large products they use:

• coarse sandpaper;
• dremel (an instrument with a rotating rod);
• a milling machine used in a nail service.

Those who are engaged in making jewelry at home should pay attention to the dremel. This small portable tool has a rotating part

Dremel attachments are used for engraving, they have different sizes and diameters. This is a fairly powerful device, but when working with it, there is a risk that small parts may be knocked out during operation. Moreover, the device has a high speed, which often leads to hand injuries. Use it to drill holes for fasteners.

The milling machine is also successfully used for work. In principle, the device is similar to the previous version, but with a lower number of revolutions per minute, so it can be used to grind smaller objects.

Another tool used for polishing is a resilient foam disc that is attached to a rotating tool. The diameter of the discs can be very different, from 10 mm to 100 mm.

Disks are rubbed with GOI paste before work. This composition was developed and patented in the Soviet Union for polishing various lenses, objectives, mirrors. It is still used all over the world.