The brass sheet is etched unevenly with ferric chloride. Metal etching

One of the methods of producing a convex or depressed pattern on metal products, which appeared relatively recently, is called etching. The operating principle of this method is based on the use of electrochemical processes in a liquid electrolyte. If you have artistic abilities, even at home you can get a high-quality pattern with a minimum of required materials and equipment.

When doing etching yourself at home, you will need the following consumables and equipment:

• a product intended for decoration - various cutlery, hunting or camping knives, or simple soap dishes on which simple patterns can be made;
• a container of sufficient volume and convenient shape made of non-metallic materials, suitable for placing the entire product being processed or its part to be decorated. It is most convenient to use glass containers for this purpose, which allow visual control of the processing process.
• a sufficient amount of ordinary table salt;
• nail polish of any color;
• nail polish remover intended for cleaning the treated product;
• source of direct electric current of low voltage. In this capacity it can be used Charger for charging car or telephone batteries.

Drawing

We start by preparing the product to be processed. It must be thoroughly cleaned of grease and dirt, rinsed hot water and dry. After this, use a brush to apply varnish to the surface of the object to be treated (in our case, these are tablespoons).

Without allowing the coating to dry completely, apply a pattern or inscription.

Depending on the design option and the desired decorative effect, when etching metals, a pattern can be obtained either pressed into the material of the product or protruding on its surface. This can be achieved by removing the protective varnish layer. It is pure metal without a beautiful film that will be subject to chemical etching.

If you want to get a convex image, leave the varnish on it and remove it from the background.

Otherwise, remove the varnish film exactly in the form of the desired pattern - it will be “pressed” into the material of the product. To obtain a fine pattern, it is convenient to remove varnish from the surface with a sharpened wooden stick or toothpick. Try to get the smoothest possible lines without smudges, which can significantly spoil the entire work of etching the design on the product.

Electrolyte preparation

After making sure that all the necessary varnish has been removed, we proceed to preparing the working solution. During this time the protective layer will have time to dry completely. As a substance in which steel products are etched, a solution of table salt is most often used at home. To prepare it, you need to dissolve the crystals in clean water in a ratio of two tablespoons of salt per 0.5 liter of liquid.

Instead of sodium chloride, you can use another quite accessible chemical called copper sulfate. It is not difficult to purchase at any hardware or garden store.

Etching a metal product

To activate the process, you must place any steel object in the electrolyte solution and connect a negative wire from a current source to it. The positive wire in this case is connected to the workpiece. Schematically the etching process looks like this:

In the absence of a high-quality converter (rectifier), you can use a phone charger by cutting off the contact for the corresponding socket.

The etching process under the influence of electric current occurs quite rapidly.

This must be taken into account when choosing a glass container. The electrolyte level in it should prevent its possible splashing out during the etching process.

Control of pattern deepening during electrochemical processing can be carried out visually by periodically removing the workpiece from the solution. If all necessary parameters are met, the process can last up to several minutes, depending on the desired depth of etching of the pattern on the metal part.

Once you get the desired result, disable electricity. After this, carefully remove the varnish film from the extracted sample. To do this, it is convenient to use nail polish remover and a thick cloth. Wash the finished drawing warm water with soap.

Getting a color drawing

To give the resulting pattern, drawing or inscription an additional decorative effect, we suggest using a simple method accessible to everyone. To do this, apply a small amount of any nitro enamel to the treated area, achieving complete filling of the recess. This paint and varnish material dries quickly enough, so you can return to further work after an hour. After making sure that the enamel is completely dry, remove extra material, applied to the surface of the etched product using fine sandpaper. The use of a solvent in this case can ruin the entire work, since it smears the paint over the surface without completely removing it, and can give the pattern an unattractive dullness.

Mechanical polishing of the finished product on a felt wheel with GOI paste will give the painted etched pattern the final expressiveness.

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Good evening everyone! Due to popular demand, I am making a MK on artistic copper etching!!
On in this example we will use Laser Ironing Technology (hereinafter referred to as LUT)!
For this we need
-Laser printer
-Iron
-Ferric chloride
-Well, copper itself
To etch a drawing, we first need the drawing itself, find the drawing, adjust it to the size you need with any program convenient for you! You need to print this drawing on a laser printer and glossy paper! If you don’t have glossy paper for photos, you can use sheets from the Natalie magazine and etc!
If you are completely hopeless, there is no laser printer or paper! We go to the nearest company where they print on T-shirts, mugs, etc.
with a pre-prepared drawing on a flash drive! Printing such a sheet costs 1 UAH! I will write prices in local currency for Russia, multiply by 3! Of course, we still need ferric chloride, you can buy it in radio stores, 200 grams of this potion costs 20 UAH!
Process!
First, we need to ferment our ferric chloride since it must stand for another 20-30 minutes after fermentation!

We take dishes from any material, just not iron, most often it’s a 0.5 liter jar, fill it with cold liquid, we need to dilute it, 10 parts water, one part cold liquid, I usually do this by eye, dilute it to the color of strong black tea! Take care of your hands and clothes!
We've fermented everything, let it sit there while all the chemical processes take place and prepare the drowned man!)
I already had a printout prepared in advance, these are such beautiful lizards, they will appear on the future pendant!!

The metal also needs to be prepared, it is important that the metal is smooth without depressions or bumps, otherwise our drawing will not be translated or will be translated with gaps, which is not what we need at all!))
I prepared a piece of copper 1 mm thick, I advise you 1 mm no less because etching, and etching reduces the thickness of the metal!
Clean, degrease, nail polish remover works well for these purposes, I use solvent 646!

After degreasing, it is advisable not to touch the part to which we will transfer the drawing with your hands!
Take the iron, turn it on, let it heat up as much as possible, then place our lizards, pattern down, on the metal

and place the iron on top, do it carefully; if there are strong jerks or shifts, the paper may move and the drawing will be smeared, let it lie there for about 5 minutes!

Then we begin to stroke our drawing with the nose of the iron, very carefully, making sure that the paper does not move, if you notice that it has moved, tear everything off, degrease it, and do it all over again!! It may not work the first time, so I make 5 copies 6 of each drawing for these circumstances!
We ironed for another 5 minutes, as you can see in the photo, the pattern began to transfer to the other side, this is good, it means everything went fine, if you do not see any part of the pattern, additionally go over the iron in that place!

Now we throw this whole sandwich into the water (we don’t throw the iron))) let it lie in the water for about 5 minutes, then we start rolling up the paper, don’t tear it off or anything like that, but roll it up, if it doesn’t roll well, let it sour some more!! Then this white coating remains, it is usually in small places, we have such places on our fingers, eyes, back! Gently remove this plaque with a toothpick, it comes off easily!!

We looked at everything to see if it translated well, there are times when something is not translated somewhere, gaps, etc., you can use a needle and nail polish to correct these gaps! We drill a hole for the thread, which we will then tie to the metal so that we can lower it into a jar and take out the time from time to see what’s there!))
The next thing we need is to protect the part that we don't want to etch, the back part can be painted over with nail polish!! I also make an outline around the lizard, for my own purposes!! You don't have to do it!!
We dried everything, tied a thread and put it in a jar, the jar can be put in a warm place, so the process will go faster! Sometimes take it out, every 20 minutes, and watch how the etching process is going!! We need to etch somewhere half the metal! For this we need 4 hours -5 etching! In general, I can’t say the exact time since it is always different!!

it's been a couple of hours

So we took out our etched part, washed it, wiped it with solvent again to remove the toner! Then we cleaned it, sanded it, and basically finished the workpiece!!
Here's a plate with a lizard!!

Don't look at how full of holes it is, I really need it!!

Electrolytic etching of brass la_pulja wrote in July 3, 2009

This entire article has been translated and compiled by user snipesp for the resource, and posted here with his permission.
Original article on English language located . Original author - Jake von Slatt

I am often asked about the thickness and type of brass used in my work, as well as where they can get it. I'm lucky because there's a specialty store near me where I buy most of my supplies. I used 0.025 inch (22ga) brass and its alloys (note: 0.025 inch is approximately 0.635 mm). As a last resort, you can buy "door kick plates" from your local store, but you'll have to clean off the varnish. If you can't find a store nearby, you can order online, but this is the most expensive way.

I recently saw Mark Frauenfelder's notebooks being released in limited quantities on BoingBoing and immediately thought of using the electrolytic brass etching process that I experimented with when trying to make similar notebooks for gifts this year.
As you can see, they turned out quite well and the two-century history of Moleskine gives the project a certain involvement in steampunk.

I adapted this technique to simply print pictures on brass plates. I say "imprint" but I'm actually using electro-chemical etching of the brass. Here's the process:
First, we use a laser printer to print the negative of our picture onto a sheet of “inkjet” glossy photo paper. Yes, I wrote “inkjet” paper, this is a special paper used, as they say, in the pharmaceutical business.
Next, we clean the entire piece of brass with light-colored Scotch Brigh and then wipe it with alcohol until it is completely clean. Several alcohol cleanings are necessary to remove all dirt.

Next, we use an iron with maximum heat to fuse the toner into the brass plate. You need to press the iron hard and rotate it a little. I used a roller to further press the paper onto the brass. In total, heating and rolling takes about two minutes.
Once you are satisfied that the toner has completely melted onto the copper, throw the plates into a tray of hot water. The water is needed to soften the inkjet photo paper so that it can be cleaned of any toner stuck in the brass.

This is actually a method that was developed for electronic circuit board enthusiasts. Please see bibliography below for more detailed information for this part of the process.
After the plate has been soaked for 5-10 minutes, remove it and carefully try to tear off the softened pieces of paper. After removing one layer, return the plate to the water.

Once you take off most paper, you can use a stiff brush to remove any remaining residue. Our goal is to have nothing left except brass and toner.

Now we move on to the elegant 19th century technology of Galvanic Etching. You may be familiar with the technique of electroplating, where a metal object is coated with a layer of another metal after placing it in a bath of source metal (which will act as a resource for the plating layer), and passing a current through them.
We're going to do exactly the same thing, except we're going to connect our plate to the anode (+) since we're trying to remove metal from it. This technique was developed in the 19th century to create prints and is still used today. Again, see bibliography in resources.

My research has shown that copper sulfate can be used to etch copper and zinc. Since I wanted to engrave brass, and brass is an alloy of copper and zinc, copper sulfate had to be the right decision for this project.
I rummaged around in the garage and found this “Root Kill” container, which is essentially copper sulfate (note: as far as I know, copper sulfate is sold under the guise of copper sulfate). I mixed about a pound (453 grams) of Root Kill with water, there is a photo below. It's all dissolved so I probably could have mixed it in slightly different proportions. From information from websites, I found out that the more saturated the solution, the faster the engraving process.
I made brass record holders from copper plated rod in hopes that the tin would not interact with the rod.

We attach the working fragment to the anode - the plus on the battery. I used 12v. 17 amp. lead acid gel cell (12 volt 17 amp hour lead acid gel cell), but you can also use a car battery, charger or a modified PC power supply unit. The circuit could use a lamp to limit the current flowing through the electrolyte, but I found that for the electrolyte I was using and the size of my plate, this was not necessary. Also, since I want a deep pattern in brass, I don't need to be delicate with the material.

After a minute or so nothing happened, although a brownish residue had formed as it worked. I removed the light bulb from the circuit and rearranged the plates closer to each other. At this distance the 16 wire I was using started to get hot and I could see the density decrease hot water around the plates in the bath. I believe the current was approximately 10-20 amps. There were surprisingly few bubbles.

After the changes, the process began to go faster. I took the plate out of the bath every 15 minutes or so and cleaned off the brownish residue. After about 45 minutes in the bath, I noticed that the toner had come off in some places after cleaning, so I took the pad and rinsed it well. I used paint remover to remove the toner and in another case I used a steel brush under running water. It worked just as well with a brush.

The plates are ready, I estimate the thickness of the etched brass to be approximately 0.5mm. The material is removed consistently and the edges where the toner was are clear and neat.

I coated the record with black primer, let it dry, and used sandpaper and light-colored tape to remove the primer from the top surfaces. Finally, I polished the plates with Noxon Metal Polish.

Here is a shot of the finished plate and the laser printed negative, as you can see the image is reproduced almost perfectly in the brass.
Below is another version of the plates I made earlier. In the photo you can see that the sword is missing a hilt at the bottom right. This part of the image was painted over using Sharpie and the ink apparently did not remain on the brass. However, on the reverse side you can clearly see Charles Buddage's different engines. I tried transferring toner from a picture printed on thin paper, but gave up because the layer of toner left on the brass was too thin.
I may try this technique again as it is quite easy and quick and definitely effective.

Warning: Some steps in this process are dangerous and this article attempts to cover them in detail. However, Greenart has extensive information about this process. I encourage anyone considering doing this to follow the link and read and understand the usage and safety information. In particular, you should read the article about the process called Bordeaux Etch as it talks about necessary measures for proper disposal of waste material.

Additions to the article in English.

Removing part of the surface layer metal product by using chemical reaction called etching. This technology has been known to man for several millennia; along with embossing and blackening, it was used to finish metal parts of weapons and household utensils, jewelry and ritual objects. Nowadays, metal etching is used in arts and crafts, for electroplating, and for creating images and inscriptions on metal products.

The essence of the method

Before etching, a protective coating that is resistant to the etching substance (mordant) is applied to those areas of the metal surface that should not be etched.

Next, the part is exposed to an acidic environment or immersed in a container with an electrolytic liquid. The longer a part is processed, the larger the layer of metal that is corroded by the aggressive environment. Metal etching can be carried out in several stages, this is the so-called multilayer etching.

Etching images on metal is carried out both in industrial and at home conditions.

Metal etching methods

Based on the materials used to corrode the metal layer, there are such methods of etching metals as:

• Chemical (liquid). Acidic solutions are used. Does not require complex equipment or expensive materials. During operation, fumes that are harmful to health are generated.
• Electrochemical. An electrolyte solution is used and an electric current is passed through it. It is characterized by a higher speed of the process, more accurate execution of the details of the design, and economical consumption of working fluid. Does not form harmful fumes
• Ion plasma (dry). The surface layer is evaporated by a beam of ionized plasma. Used in the production of microelectronic components.

The ion plasma method requires high-precision and expensive equipment and is used only in industrial production conditions. The liquid method, electrochemical metal etching and even electrochemical engraving are available at home.

Using galvanic etching, you can independently make a printed circuit board that is almost as good as an industrial one.

Galvanic metal etching

The galvanic method of etching compares favorably with the liquid etching method because there is no need to use acids that produce harmful fumes. Depending on the workpiece material, different electrolytic solutions are used:

• Steel and iron - ammonia and iron sulfate
• Copper and its alloys (bronze, brass) - copper sulfate
• Zinc – zinc sulfate.

To carry out the process at home you will need:

• Galvanic bath made of non-conductive material.
• 5 volt DC power supply.
• Metal cathode (same metal as the workpiece.)
• Wire hangers for the workpiece and cathode. The workpiece should not touch the walls or bottom of the bath.
• Two conductive rods longer than the bathtub.

One rod is connected to the negative terminal of the power supply and the cathode is hung on it.

The other rod is connected to the positive terminal and a product that will serve as an anode is hung on it.

When voltage is applied, the process of electrolytic transfer of metal from the product to the cathode begins. It will occur from surface areas not covered with protective varnish.

Artistic metal etching

Artistic metal etching is carried out using both galvanic and liquid methods.

With its help, masters of folk crafts and simply home craftsmen obtain highly artistic images on edged weapons and firearms, all kinds of forged and cast utensils. For craftsmen making designer hunting and household knives, etching has become practically mandatory element finishing. Especially popular are hunting scenes, Arabic, runic or abstract geometric patterns. Many craftsmen combine metal etching with bluing, giving the design a bluish, black or yellowish tint.

To transfer images, both the method of coating the part with varnish and glossy paper are used. Another method is also used - gluing the part with tape. Using a hot needle, scratch the lines of the design, after which, using tweezers, carefully remove the tape from the areas to be etched. Remains of the adhesive mass must be washed off with a solvent.

Before etching, the part should be thoroughly degreased.

Metal surface preparation

Before starting etching, the surface should be prepared. This will ensure:

• High process speed
• removing metal in an even layer.

During surface treatment, all mechanical and chemical contaminants are removed from it. For it, use a warm soapy solution, any detergent. After the surface has dried, it must be wiped with a rag soaked in solvent or degreaser. This will remove any remaining liquid and oil films.

It is good to combine chemical treatment with mechanical treatment:

• mirror polishing
• sanding with sandpaper. Used when polishing is unavailable. You should make sure that the skin always moves in one direction and that the marks from it are strictly parallel.

Mechanical treatment will significantly improve appearance products after etching.

Drawing

There are several methods used for this operation. What unites them all general principle: protection of part of the surface from the corrosive effect of the mordant, but distinguishes the substance used to apply the design.

Nail polish

Popular and affordable way. Has some disadvantages:

• The high viscosity of the varnish makes it impossible to draw small details and fine lines.
• Requires a steady hand and drawing skill.
• It is very difficult to correct incorrectly applied parts.

Primer or bitumen varnish

Primer GF 021, XB 062 or bitumen varnish is used. First, the entire product to be etched is coated with the substance. Next, use a thin pen or marker to transfer the contours of the drawing. A needle should be made from thin wire or a rod of soft alloys, sharpening the end of the wire.

Those areas of the image that must be etched are scratched down to the metal. Care should be taken to ensure that the primer does not chip.

Glossy paper

In addition to glossy paper (you can buy it at art supply stores, or you can simply cut a sheet out of a magazine), you will need a laser printer, an imaging application, and an iron. The image of the drawing should be mirrored and printed in life size. The image is applied to the surface and ironed several times. After the workpiece has cooled, the paper is washed off with warm water, and the toner remains on the surface of the part. The back and side surfaces that are not subject to etching must be protected with varnish or plasticine.

The main advantage of the method is that the smallest details of the image can be accurately transferred.

The main disadvantage is that you can only work in this way with flat or cylindrical workpieces. The method is very popular in the manufacture of printed circuit boards.

Steel pickling

Except artistic etching metal, which allows one to obtain exquisite images on steel surfaces, steel etching is also used to remove scale and oxide films. In this case, the requirements must be observed with particular care technological process in everything related to the concentration of etchant solutions and the exposure time of the part in the mordant or in the electrolyte bath. Over-etching during such an operation is extremely undesirable.

When etching steel, both liquid and electrochemical methods are used. The mordant is prepared on the basis of strong acids, such as hydrochloric or sulfuric. Special attention Care should be taken to thoroughly degrease the surface. A missed oil or grease stain can render the workpiece unusable. To protect parts of the workpiece that are not subject to etching, I use varnishes based on rosin, turpentine, and tar.

These components are highly flammable, so you should be especially careful and careful when working with varnish. After etching is completed, the unetched areas of the workpiece are cleaned of the protective varnish with a solvent.

Mordants used for steel

Nitric acid is very popular among home picklers. It is used as the only base for mordant, or in a mixture with tartar or salt. A metal etching solution based on a mixture of nitric and hydrochloric acid is very chemically reactive and should be handled with extreme care.

For processing hard and special grades of steel, mixtures of nitrogen and acetic acid. The processing is carried out in two stages. First, a special preliminary mordant is prepared - glyphogen, which is a mixture of water, nitric acid and ethyl alcohol. The part is kept in it for several minutes. Next, the workpiece is washed with a solution of wine alcohol in distilled water and thoroughly dried. After this, the main etching is carried out.

For pickling cast iron, solutions of medium concentrations of sulfuric acid are used.

Pickling of non-ferrous metals

Based on their atomic weight and the physical and chemical properties of the substance determined by it, for each metal and alloy they select its own mordant that best affects it.

Both pure copper and copper alloys are etched using sulfuric, hydrochloric, phosphoric, and nitric acid. To increase the reaction rate, chromium or nitrogen compounds are added to solutions. At the first stage of etching, scale and oxide film are removed from the workpiece, then proceed to the actual etching of the metal. Be careful when etching copper at home.

Aluminum and alloys based on it stand out among other metals in that they are etched using alkaline rather than acidic solutions. For molybdenum, alkaline solutions based on sodium hydroxide and hydrogen peroxide are also used.

Titanium stands even more apart - at the first stage of preliminary etching, alkali is used, and at the main stage, acid is used. For titanium I use the strongest acids - hydrofluoric and concentrated sulfuric and nitric. Titanium blanks are etched to remove the surface layer of oxides immediately before electroplating.

For etching metals such as nickel or tungsten, use water solution hydrogen peroxide and formic acid.

PCB etching

A blank for a printed circuit board is a sheet of textolite, coated on one or both sides with a layer of copper foil. The purpose of etching printed circuit boards is to create conductive traces from copper foil in exact accordance with the drawing. The tracks are covered with a protective varnish, the rest of the foil is removed by etching.

At home he uses several methods:

1. Ferric chloride. The reagent can be purchased at a chemical store or made independently. Iron filings should be dissolved in hydrochloric acid. Before use, the solution should be kept until the iron is completely dissolved and mixed thoroughly.
2. Nitric acid.
3. An aqueous solution of sulfuric acid mixed with tableted hydrogen peroxide.
4. Copper sulfate with the addition of hot water and sodium chloride. This option is the safest, but also the longest. Throughout the entire process, the pickling temperature should be maintained at least 40 o C, otherwise the pickling will take many hours.
5. Electrolytic method. You should take a dielectric container (cuvettes are good for developing photographs), fill it with a solution of table salt, place a board and a piece of copper foil there, which will serve as a cathode.

After etching with the liquid method is completed, the board should be thoroughly washed with a soda solution to extinguish any remaining acid.

Etching process for other materials

In addition to metals, other materials are also subjected to etching. The most common etching of glass is for decorative purposes. Etching is carried out in hydrofluoric acid vapor, the only one capable of dissolving glass. At the preparation stages, preliminary acid polishing of the surface of the product is carried out, then the outline of the future image is transferred to it. Protective coatings for glass are made from a mixture of wax, rosin and paraffins. After applying the protective coating, the workpiece is dipped into an etching tank.

The use of hydrofluoric acid creates a beautiful matte structure on the surface. To obtain a smooth, transparent surface, concentrated sulfuric acid is added to the etching mixture. To obtain a relief, deep pattern, the operation is repeated.

Pickling safety precautions

In metal etching, extremely chemically active substances are used - strong acids, alkalis and their solutions. If handled incorrectly, they can cause serious injury and damage to property.

Therefore, when working with them, you need to take special precautions and strictly follow the safety rules when carrying out work:

• Work is carried out only in the presence of good ventilation, preferably a fume hood.
• It is mandatory to use personal protective equipment: rubber gloves and an apron, thick work clothing, a respirator, and a protective face shield.
• Do not place jars containing acids and alkalis on high shelves and cabinets.
• When diluting acids, ACID is POURED into WATER, and never water into acid.
• When working with acid, have a soda solution on hand, and when working with alkali, have a weak vinegar solution to wash areas of the skin where drops of the solution accidentally fall.
• When working using the galvanic method, before starting work, carefully inspect all electrical equipment used for the absence of mechanical damage and integrity of the insulation.
• Have a working fire extinguisher on hand.

If the etching solution comes into contact with the skin, immediately wash the affected area with an appropriate neutralizing solution. If acid or alkali splashes onto clothing, it should be removed immediately.

If the etching solution gets on the mucous membranes, you should immediately seek medical attention. medical care. Delay in such cases can cost health or even life.