How to fix plastic. How to repair a broken plastic part

In today's time, there are a lot of mechanisms around us that use plastic gears. Moreover, it can be both toy cars and quite serious things, for example, an antenna lift in a car, a spinning gearbox, and so on. The causes of gear breakage can be different, of course, most of them are associated with improper operation, but this is not about that now. If you have already found yourself in such a situation and you have broken a couple of gear teeth, then there is a way out how not to pay for an expensive part, but to restore it in a simple way.

Required for recovery

• Unused toothbrush.
• Detergent.
• Two-component epoxy adhesive - cold welding for plastics.

Glue cold welding should be liquid, in tubes. Be sure to look on the packaging for it to be suitable for bonding plastic and plastic parts. Such a two-component adhesive can be purchased at both an auto parts store and a hardware store. If you have any difficulties and you cannot find one, at the end of the article I will tell you how to make a similar analogue.

Plastic gear restoration

Training

The first step is to prepare the surface of the gear. We wash it repeatedly in warm water with detergent, actively working with a toothbrush. Our task is to degrease and remove grease from all faces.
After degreasing is done, dry it dry.

Cooking glue

Now let's prepare the glue. Mix the components on a small piece of cardboard in proportion as in the instructions. Mix well.
In general, before opening the glue, I recommend that you carefully read its instructions, especially with the time of complete and partial hardening, since these data can differ dramatically from different manufacturers.
If the consistency turned out to be liquid, let it stand for a while until it begins to harden.

Tooth restoration

In my case, a few teeth were ground off, the situation is fixable. We smear glue on the place that needs to be restored. The glue should be very thick, but plastic.

We make such a kind of tubercle.

We put the gear on an impromptu stand so that the glue thickens even more. Everything is again individual, it took me personally about 20 minutes for the consistency to noticeably thicken.

You can speed up the reaction and reduce the thickening time by heating. For example, take a hair dryer and start heating the glue on the gear.

Tooth restoration

Now the most crucial moment - rolling the teeth. The unit where the gear was operated, namely the other gear with which our broken one was in direct contact, must be liberally lubricated with grease, grease or lithol.
We install a broken gear and roll it several times over another.

As a result, another gear rolls a track on thick glue.

Now you understand that before rolling the teeth, the epoxy glue on the gear must harden to the consistency of hard plasticine.
Thanks to the lubrication, the glue will not stick to the other gear.

hardening

We carefully remove the restored do from the mechanism and leave it for final hardening, usually for a day.

In such a simple way, you can quite simply restore broken gears.

What is a substitute for epoxy?

If you have not found the glue, I can recommend that you make a slightly similar composition.
For this you will need:

• Epoxy resin with hardener.
• The cement is dry.

We buy the usual transparent or yellowish epoxy resin with a hardener. These two components are often sold together.
In the proportion indicated in the instructions, mix the components to obtain the right amount of glue. Add cement. Only not a cement-sand mixture, but pure cement. The proportions are about two to one. That is, two parts of glue and one of cement. And mix everything very carefully. The glue is ready, and then everything is as per the instructions above.

The window sill is an integral part of the window opening. And since PVC windows are now a big priority, this part should also be made of plastic. Without this element, the interior of the room looks unfinished and uncomfortable.

But with prolonged and improper use of window sills of various surfaces, this part of the window may require restoration. And we do not always know how to update and how to repair a plastic window sill if cracks and chips have appeared, not to mention discoloration and deformation.

When Restoration Is Necessary

Plastic is a relatively practical material. Elements made from it are distinguished by ease of maintenance, ease of installation, a large variation in colors and a low price. But at the same time, they are subject to mechanical damage and are sensitive to elevated temperatures (they swell and may crack).

What to do if appeared on the windowsill:

1. Chips, cracks and scratches.
2. Traces from flower pots and hot objects.
3. Sun-bleached spots.
4. Damage caused by chemical cleaners.

The plastic surface of the window sill is subject to mechanical damage

In this case, the repair of plastic window sills is carried out depending on the degree of damage. For these purposes, there are special restorative agents. If these are minor damages, sealing is done with putty, with multiple chips and cracks, a laminated film is used, and for serious problems, a special overlay is used.

Ways to solve the problem

Let's break down the options for the restoration of PVC window sills into categories, depending on the application of the material used.

Important! Before repairing a plastic window sill with your own hands, the surface must be cleaned of dirt, degreased with alcohol and dried.

Chemical cleaners

It is known that the plastic surfaces of windows and window sills are covered with an invisible or decorative film that performs a protective function. With careless handling, scuffs and yellowing form on it. To eliminate such minor defects, it is quite easy to restore the part using a laminate wax or a special solvent-based Cosmofen cleaner.

Small stains and abrasions can be removed with a special cleaner Cosmofen

If the window sill is completely yellowed, it is better to apply the composition to its entire surface. It will dissolve the top yellowed layer and the plastic will be as good as new. This completes the window sill restoration.

Special putty

The use of a specialized mixture such as Fenoplast or Reparaturset for repairing small defects is a very popular method today. In stores, it is sold in powder form, complete with a spatula and a measuring cup. It will not be difficult to prepare putty according to the instructions. After application, such a mixture acquires properties close to PVC and easily covers cracks, be it a crack or a scratch. Experienced specialists do not use water to dilute a two-component mixture, but a primer for deeper penetration, which helps to obtain a sufficiently durable coating.

Filler can be used to repair small scratches and cracks.

Immediately after preparation of the composition should be:

1. Apply putty to the surface.
2. Carefully repair the scratch and level.
3. Wait 10-15 min. until completely dry.
4. Sand with sandpaper.
5. Polish with Fenosol S5 "UVA".

To understand how it will look like repairing a plastic window sill with your own hands using putty, you need to start from more inconspicuous places.

liquid plastic

If you do not know how to remove scratches from a plastic window sill, use liquid plastic. This material is absolutely indispensable for repairing deep scratches and large dents. It allows you to restore even the most neglected deformation.

Liquid plastic is used to correct deep defects in the window sill.

With a ready-made composition like Cosmofen Plus, all the recesses on the plastic window sill are sealed until a flat surface is obtained. After that, you need to see how the cracks and patch being repaired will differ from the overall texture of the plate. Therefore, in addition, it can be pasted over with a self-adhesive decorative film.

Laminated film

This is a fairly simple and affordable option for restoring the surface of plastic windows with numerous defects. A wide variety of colors and a choice of assortment to imitate a variety of textures (wood, stone, Russian pattern, etc.) make this product very popular even when restoration of a plastic window sill is not required.

With the help of laminated film, you can update the old window sill

To use film:

1. Apply putty mixture.
2. Eliminate the existing bulges with sandpaper.
3. Cut the film of the desired size with a margin of 2-3 cm around the edges.
4. Gently spread it over the surface with a towel.
5. Remove the formed air bubbles by piercing them with a needle and level the surface.
6. Glue the film in hard-to-reach places with a hair dryer, which will make it more elastic.

It is easiest to work with two people, when one holds the edge of the glued film, and the other removes its inner layer.

Important! Before repairing window sills, it is better to disconnect this element from the window. This will allow you to deal with the problem more quickly and efficiently.

PVC lining

Repairing a window sill with a special pad is suitable for elements with a thickness of no more than 6 cm. This is a fairly economical and completely simple way in terms of labor costs, when you can simply close the problematic part. For example, when the element could swell or crack badly. The PVC window sill lining is made of pure polyvinyl chloride, which is durable and resistant to moisture and ultraviolet radiation, and allows you to get an updated interior in a matter of hours.

To install it you need:

1. Fill large damages with glue.
2. Cut the trim to fit the window sill.
3. Degrease the surface and coat with glue.
4. Attach the overlay to the window sill and press down with a load.
5. Leave to dry completely for 5-6 hours.
6. Fill voids between window sill and trim with silicone sealant.
7. Put on the glue end caps.

After the plastic lining on the window sills is glued, the protective film is removed. The least problematic are white plastic lining. After gluing to the old window sill, the edge of the plate is heated with a building hair dryer and bent to its shape.

Plastic overlay allows you to carry out repairs in a short time

Important! Heat treatment should not be applied to laminated and glossy overlays, as they immediately lose their attractive appearance..

Dismantling the plate

If all of the above methods of restoring window sills are not suitable or the plastic is very swollen, and you no longer know how to repair the plastic window sill, you can try to radically get rid of the problem by completely replacing the part.

Dismantling the element requires some effort:

1. We cut off the mounting foam and carefully pull the element towards us, holding the slopes.
2. We remove the vacant place from the garbage.
3. We place a new plate according to the size of the old window sill.
4. We supply support rails.
5. Lubricate the side of the connection of the plate with the window with silicone sealant.
6. We install a new window sill in the connector, checking it with a level.
7. We fill the voids with mounting foam, and place a load on top of the part.
8. Remove the protective film after the foam has dried.

Important! Before giving preference to PVC windows, you should pay attention to the fact that some companies give a guarantee to replace the window sill in case of damage.

If the window sill is badly damaged, it is recommended to replace it

Installation of a PVC window sill is not such a difficult process, but it requires attention and perseverance. If you choose between replacing a plastic window sill and restoring it, then the second option is, of course, more attractive in terms of saving money, in the absence of garbage and in a variety of color palettes. And if you use a plastic overlay, then the list of materials from which the window sill can be made is not limited to plastic. It can be concrete, and wood, and brick and metal.

It turns out that the dismantling and restoration of window sills with your own hands as a whole depends on the deformation of the structures, the availability of funds and free time. And in order for this interior detail to serve for many years, you should use it for its intended purpose and properly care for the plastic texture using products specially designed for it.

Plastic has many advantages, but it also has one significant drawback - fragility. Plastic products may crack, break, pieces may break off, etc. If the damage is significant, then the thing is easier to throw away and buy a new one than to repair it, but minor damage is quite possible to fix it yourself. Restoration of plastic can be carried out by different methods, the choice of which largely depends on the type of plastic itself. On many plastic products, you can find markings with the composition of the plastic and this will help in choosing a recovery technology. So, thermoplastics are glued with a special glue, and thermoplastics are sealed. Also, the method of repairing plastic products also depends on the nature of the damage - a crack, a scratch, a chip, etc.

When repairing plastic items, the following materials and tools may be needed: solvents (for example, acetone), sanding paper No. 1000, soldering iron or plastic glue, clamps, abrasive paste, brushes or syringe, solder, plastic cleaner, brass mesh, primer and paint for plastic, grinder, varnish.

Repair plastic with glue

• Before starting the restoration, the plastic is treated with sanding paper, removing dirt. It is also necessary to degrease the place of gluing.
• Glue is applied to the crack or seam with a brush or syringe. If necessary, parts of the plastic to be glued can be reinforced with fiberglass.
• Next, combine the parts so that they do not move and at the same time tightly pressed against each other. For best results, you can use a clamp.

Soldering plastic repair

Repairing plastic with epoxy

For this method, you will need an epoxy pier and a hardener, fiberglass or serpentine tape (sold in hardware stores), acetone, castor oil, a file and sanding paper, electrical tape or adhesive tape, plastic utensils and wooden sticks, primer for plastic, polyester putty, car enamel.

Buckets, basins, barrels and other household equipment are made of plastic. This material is practical, easy to use, but short-lived.

Any drop or mechanical impact can lead to cracks. A container that passes water becomes useless. But seal plastic water container it is quite possible that she will serve well for some time.

It is quite possible to seal a plastic barrel at home. Consider two options for how to fix holes in plastic barrels and other containers.

Option 1

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

• stainless mesh (you can take aluminum, copper),
• scissors,
• soldering iron 100 watts.

Operating procedure:

1. Cut off a piece of mesh with scissors.
2. We fix the mesh at the site of damage to the depth of the mesh thickness.
3. We align it along the seam, moving along the entire plane. At the same time, we solder the mesh with a soldering iron in parallel, hold the free edge with a knife, immediately after soldering we cool it with a heat exchanger (knife) - this is an important rule so that the mesh does not bulge.
4. We introduce the entire mesh into the seam using this method.
5. At the end of the work, the seam is completely sealed and reinforced, which gives it a fortress.
6. Repeat the process on the back side of the container.

VIDEO INSTRUCTION

Option 2

If you have to repair a container with water under pressure, you can resort to another method.

For work you will need:

• flexible plastic patch
• building hair dryer,
• protective gloves.

Operating procedure:

1. We wipe the area with damage, remove dirt.
2. We begin to heat with a hairdryer at low power so as not to burn a hole, a place with a defect.
3. We heat the patch with a hair dryer from the side that will be adjacent to the crack. We heat already at a higher power.
4. We apply a patch to the place of damage and continue to warm up with a hair dryer, adding more power. Wear protective gloves on your hands to avoid burns. It is important not to overheat the surface.
5. We smooth the patch with our fingers and wait for it to cool. We pour water and check the quality of work.

Final sealing and smoothing of irregularities on a repaired plastic tank
The first method proved to be the most effective in practice. The second is more suitable as a temporary measure.

How to seal a plastic tank or a barrel for water - the choice of an epoch

If the defect in the plastic container is small, you can use epoxy glue. A two-component epoxy adhesive will effectively solve the problem of a leaky plastic tank.

Differs in the increased resistance to moisture and chemicals, polymerizes in just 1 hour, not flammable.

It is necessary to cut off the required amount of glue, knead with clean hands until a homogeneous mass is obtained, fashion a cone out of it and insert it into the tank opening. Hold securely for a few minutes.

Then you need to wait 2 hours, after which the container can be operated.

Features of epoxy adhesive "Contact":

• restores the shape of products, and also hermetically fills voids,
• is not afraid of not only water, but also oils, solvents,
• the repaired tank can be used at temperatures from -40C to +150C,
• within 3-5 minutes, the adhesive can be corrected, and after an hour it can be cleaned, turned and subjected to other mechanical influences,
• The adhesive is sold ready to use.

The cost of this composition is from 150 rubles per pack of 50 g.

Also have similar properties adhesives "General Purpos Permapoxy PERMATEX"(from 314 rubles for 25 ml) and "Plastic Weld Permapoxy PERMATEX" (from 320 rubles for 25 ml).

Epoxy adhesives can be purchased at most hardware stores, as well as online.

This post will be of interest to fans of "crazy hands" entertainment. Anyone who believes that plastic repair is not something worth bothering with, and that plastic should only be bought new and only original - can safely skip this post and not spoil your mood and myself.

Foreword

I ask in advance not to judge strictly, because I am not a big finger in this matter and there is not so much experience, but what I have, in my opinion, can be valuable to someone. I also want to say that the plastic is NOT PAINTED at the current stage, but only its integrity is being restored. There are a lot of articles on painting on the Internet, and doing it yourself in the garage is a clean water collective farm (this statement does not apply to those who have experience and equipment for professional painting).
And so where do we start. Let's start, as always, with some background. As I mentioned in my motorcycle, I initially bought it seeing that the plastic was cracked and would either have to be replaced or restored. Naturally, it is not for me to change this, otherwise you would not be reading this mini report. In fact, from the moment of purchase, I periodically rummaged through the internet and collected information on how to restore ABS plastic. There were not so many of them, except for the “masters” who “repair” anything from hot melt adhesive to cold welding. The most “correct” way to repair plastic, according to the Internet, is soldering with a building hair dryer with plastic electrodes, but for such work you need to have the hair dryer itself, electrodes and sufficient experience in using these tools. Since I didn’t have anything from the listed list, especially experience, without which plastic repair with a hairdryer could end up with the purchase of new plastic, I decided to resort to a simpler but less high-quality (again, according to the Internet community) method - namely soldering soldering iron. But if soldering was only a soldering iron, then I probably would not write this post, because. there is nothing new, as it were, and besides, with a soldering iron you cannot build up pieces of plastic that are not there. Also, on some forum, an overview of gluing plastic with the same plastic was found. It sounds strange, but in fact it is. Its essence is that the same plastic (abs) is taken and dissolved in 746 solvent (if the number is not mistaken), and the plastic dissolves well, as my experience has shown, then the seam is poured with this “glue”. To be honest, there is something in this, but for the most part garbage on vegetable oil, and a little later I will give a rationale for my statement. I did not use gluing plastic with epoxy fabric reinforced with fiberglass, because. there is experience that says that in some cases this is not reliable enough and with strong vibrations, the eboksite exfoliates from the plastic.

I will say right away: I have not yet made the plastic of the entire motorcycle, this weekend I was engaged in only three pieces that go “around the tank”. And one of these pieces had the most serious damage, in comparison with the rest of the plastic, therefore, it is on his example that I will tell what and how I did, because. the repair of the rest of the pieces is actually only a part of the actions that were applied on this piece. It is possible and only POSSIBLE, I will write another post closer to March-April where I will tell you what nuances were in restoring the rest of the plastic and about painting it or pasting it with vinyl.

Main roles

Well, we're done with the preface. So now let's look at the main characters:
Plastic:

• "displaced fractures"

• a piece of the wall (it is also a stiffener) is missing

• general view of the plastic part from the inside, traces of hot-melt repair are visible

• a detailed photo of the "hole" (the language does not dare to call it a hole) under the cigarette lighter (obviously torn out from some VAZ).

• The “ear” into which the shaft is inserted, on which the glove box lid is held, is also broken off

Patient review completed. Now a review of the "medical staff":

• Soldering iron 80 W

• A Chinese straight grinder bought back in the summer for $ 10, along with a set of nozzles, purely to see if it would fit (it did fit, but didn’t really get into the frame).
• Two-component putty for plastic (bought at the Epicenter auto department, I don’t put pictures because the company’s advertisement :) and it’s not a problem to find, there are many manufacturers)
• A set of sandpaper with different grains (I think the smallest grain is 150 or 180, the largest is 80)

• A brass mesh that was taken from the bins of the homeland of grandfather's stocks (also did not get into the frame, a similar mesh is shown below, only mine has just a wire vertically, and cables horizontally).

• Cyanoacrylate glue for a temporary fight of parts, you can safely do without it (I didn’t take a picture, any one that you sell will do)

• Steel wire 0.5-0.7mm

Let's start repairing

Unfortunately, I didn’t have any photos from each stage of the repair. often the hands are dirty and the camera / phone is not always at hand.
What did I start with. And I started with the fact that with mats I tore off the hot melt adhesive from my plastic, for the most part it didn’t really hold on, but in some places it stuck so much that it was problematic to tear it off. The part without this glue looked like this:


Then I had to completely break through the crack in order to be able to align the planes relative to each other. A simple break through was not enough, because. the one who repaired the plastic before me did not bother with this and soldered the plastic (apparently also with a soldering iron) “how it happened”, after that he filled the whole thing with hot glue on top. align planes. After this case was leveled, the position of the part was fixed with glue, this glue was also poured into cracks inaccessible places for more reliable fixation during soldering. After that, a similar procedure was done with the rest of the cracks, only with the difference that the cracks were not completely broken through, but were sanded down to plastic and fixed in the “correct” position with glue. After all the cracks were processed, it was time to solder. Because plastic was planned to be painted later, then the cracks were soldered both from the outside and from the inside. Yes, I want to note that soldering is not just “sticking” a soldering iron tip into plastic, you need to melt plastic in such a way that each time you melt plastic, you partially weld on the previous place where you melted before.

Crack fixed with glue:


The same crack but already soldered (but not yet smoothed) from the outside

After all the necessary seam was soldered, I smoothed out the crack with a soldering iron, actually leveling all the burrs left earlier, along the way, thoroughly warming up all the plastic under the soldering iron (the fingers were pretty hot on the back of the part). In such a not tricky way, all the cracks on both sides of the part were soldered.

Now it's time to start making the missing pieces of plastic, or, as some call this process, artistic modeling, and I sculpted on the basis of a metal frame and a two-component plastic putty. In my case, it was the restoration of a piece of wall with a stiffener + sealing a hole in the hole from the cigarette lighter. In the video that I will post at the end, it was recommended to use soldered wire to create a frame for the lost plastic parts. I tried this option (on a different part) and I must say that this allows you to achieve the task, but there is no convenience, because. the putty is quite “liquid” for such purposes, and strives to fall on one side or the other. Now, if I worked with a mass resembling plasticine, then such a problem would not arise. Therefore, I used a metal mesh. Its advantage is that:

• firstly, it can be soldered over the entire area of ​​\u200b\u200bcontact of the piece being restored with the "native" plastic, and not just soldered 2 ends of the wire
• secondly, the mesh can be immediately bent into a frame of the desired shape (in my case, stiffeners)
• thirdly, the putty does not fall through the seque so much and it can be applied more accurately, so as not to clean off a bunch of excess later.

And so I cut the stack, soldered along the entire fault line of the wall to which my piece adjoins, bent it as needed, cut off the excess. For a glove compartment with a hole with a cigarette lighter, a mesh patch with a diameter slightly larger than the hole itself was cut out and soldered into the rough plastic (somewhere up to the middle of the plastic thickness). After that, all soldered pieces were sealed with putty + putty was added in those places where cracks were previously soldered and too large irregularities were obtained.

Wall with stiffening rib


glove compartment view from the outside


glove box inside view


general view of the part

The putty is very smelly and polymerizes quickly only at temperatures above about 20 degrees, therefore it is better to apply it on the street, to dry it anywhere but not in the house. I did everything in the garage and dried in front of the heater.

It takes about 8 minutes for the putty to harden according to the instructions, it took me more than an hour, because. I dried it in the garage near the heater and the temperature there is far from +20 (as recommended). As the putty has hardened, it can be safely processed, namely, cleaned off with large emery.

A small digression: do not try to clean off pointwise, because. you draw to transfer all the work again or the edges of the part will float, which is not beautiful. Either make a flat long base under the emery (a corny wooden bar on which the emery is stretched) or buy a ready-made emery mount at a hardware store.

After the parts are given the desired shape, we grind the part with fine emery until a completely smooth surface is obtained.

I made the mount for the shaft of the glove compartment cover from steel wire, which I soldered deeper into the plastic. It looks like this:

Now as for the strengthening of weak points. After everything was done, a “flexibility” test was carried out, which revealed a structurally weak spot on the part, next to which there had previously been a whole scattering of small cracks. Although all other seams performed well, it was in this place that there was a risk of breaking the part or getting new cracks. To reinforce this place, an overlay was made from the same mesh and soldered into plastic with a soldering iron, but so that parts of the mesh were visible from above. Further, the same dissolved plastic was poured into the place with the grid. As summer practice has shown (and in the summer I soldered a plow that I pricked on a stump in the forest), the mesh soldered and filled with the same solution holds very tightly, and despite the fact that I reached the asphalt with a plow a couple of times very decently (I erased the bolts on the asphalt like this) that he could not insert a screwdriver) not a crack appeared in places with a grid, despite a decent load. And so the grid filled with such "glue" with plastic represents a single whole. But if such a “glue” is simply poured over the top of the sealed cracks, then nothing happens, because the adhesive layer is quite thin and during the time the solvent evaporates, the plastic layer under the adhesive does not have time to soften and properly contact the “glue”. In general, this “glue” partially had to be peeled off from my part. So I do not recommend pouring it without a grid.

In conclusion, I would like to ask you not to judge strictly.

Now a very useful video about plastic repair, which helped me a lot: