Used to repair large damage. A patch made of a sheet of metal is tightly pressed against the body, the connection to which is made with solder. To ensure the strength of the soldering, a flux is used. This method is quite simple to implement and even a beginner can do it; in terms of reliability - something between welding and gluing. Solder and flux are selected based on the alloys of the metals to be joined. Soldering is carried out with a high power electric soldering iron.
Riveted joints are used in the manufacture of bodies - this is a fairly reliable method of repair. Allows you to repair large areas of damage, change solid parts (fenders, aprons, for example). The attachment points should preferably be in an inconspicuous place. This method is better for repairing floors than welding, which in this case is rather unreliable.
The damaged area is cut out, and a new piece of metal or a fragment of a part is put in its place. Rivets must be steel - they are stronger and will not create conditions for electrochemical corrosion, unlike aluminum ones. Diameter 5 mm, for loaded places (in side members) - 6 mm. When replacing parts and their fragments, rivets are set, focusing on the points of factory welding. The rivets are painted before installation. You will need a special device - a riveter.
VIDEO
The bottom can be repaired with galvanized sheets and bolts. The damaged area is cut out. Two pieces of galvanized steel are cut out - external and internal. The floor is coated with bituminous mastic on both sides. The insulation must dry. Galvanized sheets are also treated with mastic before installation. Install the lower fragment, fix it with self-tapping screws, the protruding parts of which are cut off in the cabin. An inner sheet of metal is applied. The structure is fastened with bolts (M5 x 15 are suitable). Fixation is carried out sequentially along the perimeter to avoid bending of the sheets.
To repair large sill dents requiring replacement, the following can be applied. Several holes are drilled in the threshold, a tool is inserted into them, with which the bent section is straightened. The holes are removed using one of the above methods and, together with the residual dent, are prepared for painting.
BMW 3 series е21 Chrome ›Logbook› Body restoration. Part IV: dismantling the internal combustion engine, transmission, working with the bottom. Rotten Aloe.
Hello to everyone who has not lost hope for a successful confluence of this project! I hasten to please you - the restoration is not frozen, not stopped, everything is just beginning!
That month I did not write anything in the BZ, although there is something to talk about. And, getting closer to the matter, I would like to note that your humble servant has finally become a certified specialist! 6 years of study in a neighboring city remained behind, now there is time to take up the project more thoroughly)) Here, in person, defending a diploma, red, by the way =) And not just red, but on the topic of auto restoration))) So in the comments, be the first business I accept congratulations! 🙂
He praised himself, you can calmly move on to pressing matters! Let me remind you that in previous articles we talked about the manufacture of threshold amplifiers and the installation of their original repair elements. To continue the restoration work, it is necessary to make some changes to the technical equipment of the car! Namely, to dismantle the elements that interfere with the high-quality restoration of the body: engine, transmission, fuel system (tanks, lines), suspension elements. And below you will perfectly understand why it is extremely important to make the maximum possible disassembly of the body!
It was decided to start dismantling from the heaviest (literally and figuratively) element - the engine with everything attached except for the box, since removal was carried out without a lift "up" by the force of 4 male labor forces =)))
Further, the freshly dismantled internal combustion engine calmly went to temporary rest. Where, you ask? Of course, to my grandmother's yard, which during my "non-writing" acquired a solid canopy! And you say I'm not doing anything))
And what do we pay attention to after removing the engine. And here's what: tired spars 🙁 On the left, some "craftsmen" not wanting to bother, to put it mildly, with a problem area, have installed a corner! Wow, it turns out it is possible to solve such a question with little bloodshed ... well, isn't it? The right side promises to be less problematic. At first glance, it promises ... we know that it is not!
We remove the corner, contemplating the horror that awaits us. The inner tubes containing the long bolts of the beam fastening were eaten by mice about 20 years ago. will have to restore the structure. On the right, we managed to solve the situation with a patch, but this is not the final yet, we will soon continue the topic with the Longs!
Well, it's time to move on to restoring the bottom.Let me remind you that the work is carried out without a lift in the old fashioned way, using the old-fashioned method of "throwing" on the side 🙂 In this matter, invaluable help was provided by a "gadget" made by a master for such purposes! Here it is in all its beauty: long rails with a movable hub locking mechanism! It is important to note that the cutouts for the calipers are not forgotten on the mating plane =)
Hello everyone, it's no secret that there was a problem with the doors on Ksenia and most likely there will always be, and I also ran into this problem. My car is already 12 years old, the doors began to rot for about 4-5 years, but everything was bearable for the time being until the time, cleaned, tinted, and so every year. But a year ago, through holes began to appear, then pieces of metal just started to fall off in the corners of the doors, initially I wanted to cut off the bottom of the door and just weld on new iron, but broke off with the welding one and had to go the other way, in this thread I will show and tell you what and how I did. By the way, about buying a new or used door for some reason it turned out to be problematic, nowhere, and the price of a new door will be somewhere in the region of 5-6 thousand rubles. and I spent about 700-800 rubles for 2 doors and one day of work. And so let's start.
1. we clean up the places of rust (I used a grinder) in some places even just cut off the metal.
2.because it rotted down, then the outer sheet of the door just came off from the door itself (from the bottom) it was necessary to connect these two halves, for this I used car plasticine (as a sealant, I covered the joint from the inside, removing the trim), I also I smeared metal plates (you can use steel wire) to make the bottom edge of the door, which I simply inserted between the “halves” so that they would not fall out during operation, it looks like this:
3. Then on this whole story we put putty with fiberglass
4. To clean up (since this putty is not very malleable to processing, I again used a grinder)
5. Then we apply the putty, but already the finishing
6. We clean it with sandpaper
The last two pictures were taken after the rain, and visually it seems that there are jambs, but in fact the door turned out to be perfectly flat and with normal gaps.
1. Putty with fiberglass about 240 rubles. (I still have more half-a-line)
If I help someone, I will be glad, write if anyone does not understand anything.
method of repairing a "rotten" car threshold with your own hands.
Replacing the threshold is not an easy job for a craftsman and not a cheap pleasure for a car enthusiast. Some I had to hear from my clients "Can you somehow do without a replacement?", And there really is a way out, repair of the threshold with fiberglass.
The lower part of the threshold has large metal corrosion centers. It is not possible to repair using welding and patches, we will glue it from fiberglass.
Using a metal drill bit, we clean the area of corrosion and an area of 5-10 cm. Around.
Removal of corrosion.
At this stage, it is necessary to process the corrosion center, this is necessary for better adhesion of materials. We will use a well-known tool called "Rust converter" ... It is quite easy to use, you just have to follow the instructions on the product.
We fill in the missing cavities ("matrix", "blank").
To fill the void, you can use various means such as: plasticine, cardboard, polystyrene, wood, etc. In this case, the most optimal and convenient to use is polyurethane foam. Under its weight, the foam tends to "fall off", so you need to prepare in advance for this unpleasant moment. To do this, you need to prepare a stand, all the various tools at hand will do. In my case, it is a wooden board. To facilitate further work, I advise you to cover the stand, for example, with newspapers or film, since it will be quite difficult to separate the foam adhering to the tree.
Before starting to fill the cavities with foam, lightly dampen the surface with a regular garden sprayer. This is necessary for better adhesion to the metal.
We are waiting for the foam to dry.
Using a knife, we cut off the foam and create the most approximate shape of the threshold. For a more accurate removal of the plane, the foam can be leveled with a bar with P40-60 sandpaper.
Working with fiberglass requires some knowledge and a lot of patience. Before starting work with composite materials, it is necessary to protect the body from accidental ingress of resin drops. To do this, I advise you to cover the body with paper or film. The repair surface must be well cleaned and degreased. We dilute the polyester resin in the required amount. Polyester resin is diluted in a ratio of not more than 2% of the catalyst by volume of the resin. Using a brush, saturate the entire surface with resin, then apply glass mat with a density of 300gr / m2. For ease of use, it can be divided into two parts and we get the 150th. This is necessary so that the glass mat does not fall from its weight from the lower part of the threshold, so the build-up of layers should be done gradually, after each layer has dried. Two layers of 300 glass mat will be enough. To insure against "sliding" of all this mass, make some kind of support under the lower part of the threshold. When the resin is dry, the resulting fiberglass must be prepared for the application of the putty. Grinding with coarse abrasive P40-60.
We apply putty.
Absolutely any putty on fiberglass can be applied. If a thicker layer is required to level the surface, then it is better to use a filler with fiberglass, then universal or with an aluminum filler. After leveling the surface, it is necessary to prime it, apply an anti-gravel coating on top of the soil and paint.
This method can repair not only the thresholds of the car but also arches, fenders, doors and more. All this, of course, is not durable, approximately the service life of such a structure ranges from 2-5 years, of course it still depends on the quality of the master.
I want to talk about what corrosion of the body metal can lead to and how to deal with it when it is too late to do prevention with chemistry and protective coatings.
So, I own a Mazda Familia 1995 1.6L BHA6R body.
In the spring, the cabin began to smell disgusting of rotten earth and rotten potatoes. Cleaning, washing and drying the passenger compartment did not work. It was decided to disassemble the entire cabin to find the center of the stench.
For this, the seats were unscrewed and removed (the smell was clearly not coming from them), the carpet was removed.Under it were sheets of soft felt insulation. The carpet and insulation were washed with detergent and dried. The seats were ventilated outside for several days and roasted in the sun.
Well, the interior is disassembled, but the smell remains.
What we see: along the empty beam, the floor metal has rusted and turned into dust. One push with a screwdriver is enough to create a hole. On closer inspection, the rusty dust turned out to be saturated with moisture, like a wet sponge. It was from her that this disgusting smell came.
When putting your car in order, sometimes you have to find an unpleasant problem - a through hole in the bottom of the body. Some car owners immediately seek help from a car maintenance service, while others try to seal the hole on their own. In the second case, you have the opportunity to save time and finances, as well as be able to master new auto repair techniques, which is always useful and relevant.
Many people do not have a large number of repair and construction tools and equipment, so not every car owner has a welding machine in the garage or workshop. In fact, if the hole in the body is no larger than a matchbox, it is quite possible to repair it yourself without welding. There are several ways to do this:
cover the hole with putty;
solder a metal patch;
seal with epoxy;
apply fiberglass and glue;
install riveted joints;
use galvanized sheet metal.
In the area of the hole in the bottom, remove the damaged coating, that is, the old layer of paint, and clean the metal, treat it with a special preparation - a rust converter. Then the working surface is degreased and primed. Next, a solution of a putty of a homogeneous consistency is prepared. For greater efficiency, fiberglass is added to it (most often with large elements). Then the composition is carefully applied to the damaged area. Perhaps this is the most important part of the job. It is necessary to close up the entire hole, cracks and microcracks that may arise around it. The application of the solution should take place in several stages, allowing each new layer to dry.
To achieve maximum fixation of the putty on the damaged area, a backing is applied to the back side. It does not allow the solution to spread, but to act in the area that needs to be repaired. If the hole in the bottom of the car is large enough, this repair method can also be used with auxiliary elements. Instead of a lining, a metal mesh is mounted in the damaged area. Therefore, the putty is evenly distributed over it, filling the entire space. After the solution is completely dry, the area is treated with automotive paint putty. Then the damaged area is painted and a protective film is applied.
This method of filling holes in a car is the simplest one. But experts do not recommend using it, since the putty allows moisture to pass through and can deteriorate over time. Also, holes are treated with a solution when repairs need to be done urgently, and there are no other alternatives.
Soldering a metal element into a damaged area is a way to seal holes in the bottom or any other part of a car, when a small hole can be closed. To repair a car using this technology, you must have the following tools:
a piece of sheet metal;
powerful soldering iron;
flux or rust converter;
putty;
primer.
So, first, the area that needs to be repaired is cleaned, paint, rust, dirt are removed. Then it is treated with flux and degreased.Then measurements are taken and a metal piece of the desired shape is cut out. Such an element will completely fill the hole, and the edges will overlap. When the part for the patch is ready, it is attached with a soldering iron. Then the edges of the patch are treated with flux. At the end, it is worth treating the area with putty and priming it. When the surface is dry, paint and a protective layer are applied.
This method of sealing holes in the underbody of a car is the most popular. Experts note the durability of the soldered patches, since the connection is quite reliable. In addition, this method can be used to close a hole of any size. In general, soldering the patch is quite simple, which can be done even by a beginner who does not have much experience in repairing cars.
For moderate damage, the method of filling holes with glass cloth is often used. When this area has been processed and cleaned of layers of paint and rust, it is necessary to cut out several overlays from fiberglass, measuring the size of a hole plus 2 centimeters. This area should be pre-primed and allowed to harden.
An overlay is applied to a dry surface and fixed with a mixture (polyester or epoxy resin + glue). The next "detail" is attached and also fixed. Thus, all fiberglass parts are glued, putting them one on one. To prevent them from sagging or deforming, you should put a lining. When the resin and glue is dry, you need to treat the work area and paint it.
Processing holes in the bottom of a car with galvanized metal is quite common. The main material required for this is sheet iron. Before installation, it should be secured with self-tapping screws and lubricated with mastic. It is best to use an anti-noise bitumen mixture. Then the galvanized steel is laid and bolted with a drill. Then you need to treat the area with special means, level the entire surface. When everything is dry and the structure is fixed, it should be covered with paint.
VIDEO
Another reliable way to plug holes is to make riveted joints. Large and small holes can be closed with this technology. To do this, the damaged area is cut out, the edges are cleaned of paint and rust. Next, rivets are cut out of steel, since they are the least susceptible to corrosion. Then the part is attached and fastened with these rivets. When the structure is completed, the entire area is painted.
Video (click to play).
So, there are several ways to seal holes in the bottom of a car without welding. You can use any method described in this article. Choose exactly the option that you are able to implement. And remember, any task is possible and very pleasant to carry out on your own.
