Polishing and processing of products made of PLA, ABS, HIPS, PETG, SBS dichloromethane solvent. Polishing and processing of products made of PLA, ABS, HIPS How to dissolve plastic

Sometimes acetone is used for finishing (polishing, steam processing and even gluing) of ABS products. With the same success, some use methyl ethyl ketone and dichloroethane (both highly toxic) for these purposes. But tetrahydrofuran and dichloromethane cope best with this kind of task, with only one difference - tetrahydrofuran is a precursor and is prohibited for free sale. The solvent is universal and suitable for all types of plastic: ABS, PLA, HIPS, SBS and some others. To smooth and melt HIPS and SBS, we use the safest solvent we know of, D-Limonene, not only is it harmless, it also smells like delicious oranges. Often used as a flavoring agent.

Remember: dichloroethane is a strong poison. Dichloromethane is less toxic. Tetrahydrofuran is relatively non-toxic, but is not commercially available.

When working with this substance, or any chemical, you need to take serious safety measures. This method is one of several possible for processing products.

WARNING:

We describe methods that CAN be used, but require reasonable precautions. Please read the chapter “Safety Precautions”, read the safety data sheet of chemical products, and we will consider that we have warned you.

Why is post-processing needed?

As a result of fine-tuning, irregularities at the junction of layers that arise during the 3D printing process (by layer-by-layer fusing of filaments), various kinds of process artifacts (such as points of contact with fasteners) and other minor defects are smoothed out. The piece ends up looking less “layered” and more neat. Look at the photos below or Google it.

Dichloromethane

Get Additional information You can, for example, on Wikipedia. Please note: Although it is the least toxic of the haloalkanes, care must be taken when handling as it is very volatile and may cause acute poisoning. Work should be carried out while the exhaust ventilation. To the best of our knowledge, this is the least toxic solvent for PLA plastic, but extreme caution should be exercised when working with it as its long-term effects are extremely dangerous. It is flammable, so avoid contact of its vapors with open flames or sparks. The same applies to acetone, tetrahydrofuran, etc.

Its important property is high volatility. Hazard class IV, the same as acetone. The smell is much weaker than acetone. It is advisable to carry out all work in a well-ventilated area!

Do not pour dichloromethane into a toilet, sink or other plumbing fixture; it does not mix with water and plastic pipes your sewer system may be at risk.

D-Limonene

Less harmful, one might say safe solvent D-Limonene, strong citrus scent. But it only affects HIPS and SBS plastic. We recommend working with it in a well-ventilated area. D-Limonene is oil based and must be washed with soap and water to neutralize the plastic and solvent reaction.

Whenever you work with solvents, you should always wear gloves because they can quickly dehydrate the skin, which is potentially dangerous. Using strong solvents can easily cause skin burns. The gloves should not be latex (latex corrodes), but nitrile or neoprene.

The easiest way is immersion processing

Very simple and fast processing, one printout takes no more than 3 minutes. We immersed Yoda in dichloromethane for 1-5 seconds, and over the next 1-2 minutes the solvent completely evaporated from the surface. To make a glossy surface, dip the part into the solvent for the last time for 0.5 seconds, it will not have time to be absorbed and will immediately evaporate, a candy-like gloss is guaranteed.

Very quickly, no need for a bath, no need for acetone. Dichloromethane is universal for PLA, ABS, HIPS, and possibly many other exotic materials. A liter lasts a long time. The tightness of the container for storing the solution is very important.

Application by brush

Using any clean natural brush, apply dichloromethane until the layers are smooth. This solution is extremely volatile, so you won't have to wait long for it to dry. The obvious advantage of this method is that the solvent can be applied selectively, leaving sharp corners not touched, and the most noticeable printing defects should be processed more carefully. The best processing results are achieved precisely in this way. Take precautions, breathing chemicals is not safe!

Processing in pairs

Procedure PLA processing in pairs is essentially the same as in the case of ABS and acetone. Tetrahydrofuran is used here. The PLA object to be processed is placed on an insoluble support (aluminum foil, wire mesh, wooden stand etc.) and placed in an airtight container. When heated, the solvent will begin to evaporate and interact with the surface of the object.

As an example, this shark tooth was printed on a Makerbot Replicator 2 in brown PLA, treated with THF fumes, and dried.

Note the unevenness at the top. Here the object touched the support during finishing. Therefore, it is always important to think about what to lean against what. Also keep in mind that the smaller the volume of your chamber, the more difficult it is to correctly time it so that the gas inside is distributed evenly. Because of this problem, the alignment itself may be uneven.

Now, a few words about additional measures security that we promised to mention. All procedures should be done outdoors, and the flask, jar, bottle or other container should be tightly closed. Wash the inside of the cabinet before and after use. In short, you need to work carefully and smartly so that you don't accidentally burn or explode something.

Hand polishing

Don't like steam processing? You can polish by hand by applying solvent to a piece of cloth.

The cloth should be white (not dyed), lint-free and used only for this purpose, because PLA will accumulate on it and it will no longer be suitable for anything else.

Once you have found a suitable cloth, put on nitrile or neoprene gloves, go to a well-ventilated area or outside and dampen the cloth with dichloromethane. And now just polish the part with this wet cloth. Final result will depend on the direction of your movements, the force applied and the texture of the cloth, i.e. how tough she is. Unless there are any special reservations, it is best to polish in a circular motion.

The object must then dry (so that excess dichloromethane evaporates from the surface) and you are done.

Here is a sample of a polished shark tooth that was printed on the Makerbot Replicator 2 using white PLA.

These photos are in focus. They were taken with macro photography, the depth of field is relatively shallow so that only the main focus stands out and details can be seen, although the edges of the image are blurry.

Only the middle of the tooth was polished, the part that stands out. It's not entirely clear from the photo, but it is a very smoothly polished surface. Compare it to the left edge, which was not polished, where even the layers of the print are visible.

Obviously, the smaller your object, the higher the print resolution (if everything is calibrated correctly), the less time you will have to spend on finishing to get a well-polished, smooth surface.

You can also see in the photo that the treated surface has become slightly discolored. But the point here is skillful hands. The rag was not completely white, there was some kind of colored pattern on it, and the paint reacted with the solvent and at the same time with the plastic.

Addendum: Other Post-Processing Techniques

It should also be noted that PLA is easily sanded with regular sandpaper. In some cases, it is quite enough to get the surface as it should be, especially if you only need to remove traces of support or similar defects. Stripping is very useful also before chemical treatment. Just go over it with sandpaper problem areas and especially large artifacts, and then proceed as described above. This will save both time and reagent, and the finishing will be more accurate, without significant geometric distortions.

How to glue PLA parts?

PLA parts can also be glued with various glues, we worked well with epoxy and with Super Glue (super glue second), which is actually just ethyl cyanoacrylate.

Good luck! Safe work! Smooth printing!

Can be done using various means: acetone, methylethylethane, dichloroethane, tetrahydrofuran and dichloromethane. For safety reasons, it is preferable to use tetrahydrofuran and dichloromethane for these purposes, since methyl ethyl ketone or dichloroethane are highly toxic. Acetone is not very good for similar reasons, although it is a very affordable solvent. For materials such as ABS, PLA, HIPS, SBS and other types of plastics, solvent is used quite often. However, experts recommend as a more safe alternative D-Limonene product. In addition to being safe, this solvent also has a pleasant citrus aroma.

Safety - important condition when performing post-processing, therefore, it should be borne in mind that a number of substances, such as dichloroethane, are classified as powerful poisons, so they cannot be used. Dichloromethane is considered less toxic, but it also poses risks to human health. Not very toxic tetrahydrofuran is almost never found in the public market.

Warning:

Methods proposed in the article production process require strict adherence to safety measures. Therefore, before performing work, you should carefully read the chapter “Safety precautions when working with solvents”, safety data sheets for chemical products.

Post-processing of plastic: the essence and objectives of the process

In the FDM 3D printing process, we obtain objects with obvious traces of layering (irregularities), as well as various artifacts of the production process (traces of points of contact with fasteners and other visible surface defects). Post-processing serves to smooth out uneven surfaces and remove unnecessary artifacts, after which the processed object will look much better.

Safety rules when working with solvents

Dichloromethane

Since the 19th century, dichloromethane has been classified as relatively non-toxic and very effective means for plastics, which has been proven by numerous laboratory research. But this solvent also has disadvantages. When connecting with alkali metals Dichloromethane may cause a violent explosion. The mild volatility of the product leads to rapid and severe poisoning of the body and damage to a number of important internal organs. Therefore, it is recommended to carry out any work with dichloromethane in the presence of properly functioning exhaust ventilation.

Do not allow the substance to come into contact with fire or sparks, otherwise it may cause a fire. Do not pour dichloromethane into the toilet or sink, as the substance does not mix with water and can damage plastic fittings. In its properties, dichloromethane is very similar to acetone and tetrahydrofuran. It has the same high volatility and hazard class IV. Although the odor of dichloromethane is weaker than that of acetone, ventilation of the room should not be neglected.
D-Limonene

Among the currently known solvents used for working with plastics, D-Limonene is rightfully considered less harmful and relatively safe for humans, provided that all precautions are strictly followed. The citrus aroma makes working with the solvent more pleasant. However, it is necessary to ensure that the room is well ventilated, since prolonged exposure to the substance has a negative effect on the human body. D-Limonene soap base makes it easier to neutralize the reaction of plastic with solvent, since in such a scenario it is enough to use water and soap. The only one significant drawback substance is the fact that it interacts only in HIPS and SBS plastics.

Please note that no matter how relatively safe the solvent is, when working with it you should use gloves and ventilate the room well. Gloves will help prevent skin damage or dehydration.

Processing methods

Dip processing method

Dip processing is the simplest and most quick method, because one cycle lasts a maximum of 3 minutes. An example is immersing iodine in dichloromethane. The immersion process lasted several seconds, and after a few minutes the solvent completely disappeared from the surface of the object. If you want to get a glossy surface, the product can be immersed in the solvent again for about half a second. This will be enough so that the solvent is not absorbed and quickly evaporates, and after the operation you get a glossy surface.

The duration of the process is very short also because for such purposes a bath and acetone are not needed. For ABS, PLA, HIPS and other rare Supplies Dichloromethane is fine. One liter of product is enough for for a long time, the main thing is to maintain the tightness of the container with the solution.

Brush method

In this case, dichloromethane should be applied with a clean brush with bristles made of natural hair. The substance, by the way, is very volatile, is applied until the surface is completely smoothed at the places where the layers come into contact. Dichloromethane is excellent when selective application of solvent is required to leave corners intact and remove obvious defects. Practice shows that this method allows you to achieve the best results in the post-processing process. And, of course, do not forget about observing safety precautions.

In addition to dichloromethane, a substance such as XTC-3D from Smooth-On is very useful for high-quality surface treatment with a brush. This material is protective covering of two elements and serves for high-quality alignment and finishing 3D objects. During the processing process, two types of liquid are mixed, and then the mixture is applied to the surface of the product with a brush. The application procedure must be completed within five minutes. Curing occurs within 4 hours, depending on the mass of the object and temperature. XTC-3D has a number of important properties: It creates a hard, impact-resistant finish that can be sanded, primed or painted.

The manufacturer claims that XTC-3D can be used for products produced using SLA and SLS technology. The substance works excellently with PLA, ABS, Laywoo, polyurethane foam, wood, gypsum, cardboard and even paper. Externally, XTC-3D is similar to ordinary epoxy glue, and the substance does not have an unpleasant, persistent odor.

Steam processing method

Treating PLA with vapor is similar to treating ABS with acetone. Tetrahydrofuran is used as a processing agent. The PLA product being processed must be placed on an insoluble support. For these purposes you can use aluminum foil or wire mesh. After this, the product is placed in an airtight container. The solvent evaporates when heated and interacts with the surface of the object being treated.

In the photo above, the shark tooth was made on a Makerbot Replicator 2 using brown PLA plastic, then treated with THF and dried.

If you look from above uneven surface, you will understand that during post-processing there was a place where the object came into contact with the support. This suggests that before work you need to think carefully about which part and where to lean the product. Calculating the time for uniform gas distribution inside the chamber becomes more difficult the smaller the volume of the printer's working chamber. The unevenness of the leveling process can be explained precisely by this reason.

Manual polishing method

The manual polishing procedure is familiar to many, and if you do not want to use the steam processing method, then you can pay attention to this quite simple and effective method. The solvent will have to be applied to a piece of fabric and polished by hand. For this procedure, use a white or undyed lint-free cloth. Otherwise, PLA particles will remain on the fabric, and then you will not be able to use it again.

The use of fabric does not exempt you from observing basic safety precautions. The room should be well ventilated, and nitrile or neoprene gloves should be worn. The fabric needs to be wetted with dichloromethane and after that you can start polishing. The result of the work is determined various factors: how the movements were performed, what forces were applied, and even how stiff the fabric was. Polishing is usually done in a circular motion unless otherwise noted.

After completing the polishing procedure, the product must be allowed to dry. In this case, the substance will completely evaporate.

The photo was taken with macro photography, the depth of field is shallow, but the main focus is highlighted in order to see the details. The middle part of the tooth was polished. The results were very good. For comparison, pay attention to the left side, where print marks are visible.

It should be remembered that the size of the object and the printing parameters determine the amount of polishing effort. How smaller product and the higher the print quality, the correspondingly less effort.

Materials for manufacturing

To make liquid plastic with your own hands, you need to prepare the following:

container made of glass or metal;
acetone;
Styrofoam.

In this case, the amount of acetone used depends on the desired volume of the finished product.

If you want to make liquid plastic with your own hands, the recipe for its preparation will be based on dissolving polystyrene foam in acetone. For this purpose they use It is a packaging container for various household and electronic equipment.

How to make liquid plastic with your own hands

Step by step recipe The preparation of the named material looks like this:

Open the container with acetone and pour the liquid into the glass container so that its level from the bottom is approximately 1 cm.
Polystyrene foam must be broken into many small pieces, each of which will be easily placed under the thickness of the solvent.
Liquid plastic You can do it yourself by dropping each piece into a container and waiting for it to completely dissolve.
Polystyrene foam should be added to the container until it stops melting. Then you need to wait 5-10 minutes for the unused acetone to evaporate.
After this, a viscous mass is formed at the bottom of the container, which can be used to produce a variety of products.

Knowing how to make liquid plastic, remember that complete hardening of the mass lasts 20-30 hours. Consequently, the part being manufactured cannot be removed from the mold within this period of time.

Apply the substance with a rubber spatula small size. Movements should be smooth. Liquid plastic must be stretched over the surface to be treated. If you use it to fill cracks, it is better to use brushes with hard bristles. They need to “push” the mixture into the gaps. After the plastic has hardened, it is recommended to apply another layer of the substance.

The described product has long been sold in finished form. It only needs to be heated in a water bath or in special equipment. A hair dryer is also often used for this.

As a rule, liquid plastic is produced in dense packaging. Its terms and storage conditions are strict. The temperature in the room where it is located should not fall below 15 degrees. Otherwise, the product will lose its performance characteristics:

viscosity;
elasticity;
hardness after hardening;
practicality;
durability.

The cost of liquid plastic is quite high. That's why it's better to do it yourself.

Precautionary measures

Acetone is a very dangerous liquid that has an extremely negative effect on the human body. Therefore, it is allowed to make liquid plastic with your own hands only with strict adherence to following measures precautions:

Before working with acetone, you must carefully study the instructions for its use. It is indicated on the container label.
Special sealed safety glasses should be used. They will protect your eyes in case of liquid drops and vapors. Working without them can cause serious eye injury.
Acetone is toxic, so it should only be used in a well-ventilated area. In this case, it is necessary to use respiratory protection.
This is a highly flammable product. Therefore, liquid plastic is made with your own hands away from sources of open fire. Smoking is strictly prohibited when performing work.
Residues of acetone must not be poured into the sewer system.
At the end of the process, as well as after pouring the finished plastic into molds, you must thoroughly wash your hands.

Applications of liquid plastic in finishing

The product has been used for finishing for a long time. After its application, an elastic film appears on the treated surface. It is highly waterproof and UV resistant. The material protected by such a film is not afraid of exposure to aggressive detergents. Smooth surface has a pleasant shine and retains its characteristics for many years.

Liquid plastic in window work

Most newly installed plastic windows there are gaps in the connection area. To exclude such a phenomenon, all details window design, which are connected to each other, are treated with the described substance. After drying, it creates an elastic, sealed film on the surface. Applying liquid plastic to windows with your own hands is possible after making the material according to the above method.

Anti-corrosion agent

Liquid plastic is also characterized by a high degree of adhesion with the processed material. metal surface. This property of the substance began to be used in anti-corrosion treatment of steel. Liquid plastic is applied to the surface without prior priming. It dries out in a few hours. After this, a film is formed on the surface that will protect the material from rust.

Greetings!

On the pages of thematic resources, questions still often appear about how to process and glue this or that plastic. Moreover, the answers sometimes cause bewilderment. Apparently, there are a lot of myths and confusion in this matter.

In this regard, I decided to write a short educational program on basic plastics and solvents, especially since I personally smelled almost all the chemicals that will be discussed.

So, let's go!

Dichloroethane

You can hear different opinions about dichloroethane. Some say that it is very poisonous, others claim that they have worked with it without gloves all their lives. Apparently, this is due to the fact that dichloroethanes come in different varieties.

1,2-dichloroethane (ethylene chloride) - dangerous toxin!(second class). 1,1-dichloroethane (ethylidene chloride) is 5 times less toxic, but also far from being an air freshener (hazard class 3). Personally, I do not recommend checking for yourself which dichloroethane was sold to you.

I mention this chemical only because it is quite common and cheap and is sold in small vials, so it can help out in a critical situation when there is no more at hand. suitable option. Don't forget about safety precautions!

Dichloromethane(methylene chloride, methylene chloride)

Colorless volatile liquid with a faint odor. The best option for working with PLA. It has the same hazard class as acetone - fourth. Cheap, but difficult to obtain at retail in the provinces.

For reference:

PLA is also soluble in tetrahydrofuran and 2-methyltetrahydrofuran (hazard class 3).

Acetone

Acetone does not dissolve PLA as we need, but with prolonged contact the plastic swells, warps and softens. This can be used if the nozzle is clogged when printing PLA. When soaked in dichloromethane, plastic turns into slime, which can be difficult to clean completely.

But after soaking in acetone, the softened PLA will be removed from the nozzle in one lump, along with the blockage.

I came across opinions online that PLA dissolves in limonene and high-octane gasoline such as Galoshi. It is not true! PLA does not interact with these substances in any way.

Again, dichloroethane and dichloromethane.

Acetone- I think it needs no introduction.

Ethyl acetate(4th hazard class) - not as smelly as acetone (rather even aromatic). It is more convenient to work with it, because... it does not evaporate as quickly as acetone and dichloromethane, but it can be difficult to find.

Dichloroethane, dichloromethane.

Limonene(d-limonene) is an oily liquid with a strong citrus odor. Expensive and difficult to obtain in the provinces. Compared to our other solvents, it evaporates very slowly, so it is convenient to work with, but you need to get used to it, because... it works for a long time. For example, after dipping for too long, the model will not “float” immediately.

The safest of our chemicals.

SBS (Filamentarno, Watson)

Here I will simply quote information from the Filamentarno website. Well done guys, they sorted everything out before me.

Solvent(nefras) GOST 10214-78

It dissolves perfectly and gives T-Soft series plastics a unique transparency similar to glass. Excellent fusion and leveling of layers. After processing, the plastic does not become cloudy. Solvent treatment is recommended in a dry, well-ventilated area.

D-limonene

Slowly and gently dissolves plastic, requires longer drying with warm air (using a hairdryer). IN pure form(citrus terpene) does not cloud the product when it dries. After processing it leaves a pleasant smell of tangerines on the plastic :)

Dichloromethane

Prototyper dissolves well; when dry, the plastic becomes cloudy, acquiring the effect of foggy glass. It evaporates quickly and has virtually no odor.

Safety precautions

For all of the plastics mentioned, there are solvents with a hazard class of 4 or lower. It's better to use them. These are mostly volatile and flammable substances, so work away from fire, ventilate, read the safety rules on the label.

In Ob it costs around 600 rubles.

Polypropylene gloves are suitable to protect your hands, because... polypropylene is resistant to all our solvents (therefore you can use polypropylene containers, syringes, etc.). But you can also use ordinary household ones, just be careful. Upon contact with dichloromethane, they begin to degrade, but not very quickly.

For example, it is quite possible to wet a cloth and walk over a medium-sized model.

It seems like I haven't forgotten anything. Thank you for your attention.