Do-it-yourself cast iron bathtub repair: common damage and how to fix it
The main defects in the bathtub coating include cracks, scratches and chips.Damage occurs after careless installation of furniture, plumbing fixtures and heavy objects falling into the bathing bowl. Calling a professional to fix problems won’t be cheap, so it would be nice to learn how to repair a cast iron bathtub yourself, don’t you agree?
We will help you resolve this issue. The article provides detailed instructions for removing chips, small and deep scratches, and also describes effective methods for restoring cracks. By studying the material, you can restore the attractiveness of a cast iron bowl and extend the life of the bathtub.
The content of the article:
Removing shallow scratches
The use of multi-component cleaning products, cleaning the contaminated surface with a stiff brush, careless handling of metal objects during repairs - all this leads to the formation of shallow scratches.
Such scratches must be eliminated immediately, since the penetration of moisture and caustic chemicals into the resulting gap leads to the formation of rust, the proliferation of moisture-loving microorganisms and an increase in the size of the scratch. Which will lead to further destruction of the bathtub surface.
Factory enamel on the bowl cast iron bath very durable, so to remove shallow scratches you need screwdriver. If it has already been restored with acrylic or epoxy enamel, sanding paper will be suitable for treating micro-scratches.
In addition, for processing microdamage you will need:
- fine grit sandpaper markings P1200, P1500 or screwdriver with an attachment for attaching an abrasive wheel;
- fine abrasive automotive polish — ekonomic polishes for disposable use are pastes from the company WILLSON And RUNWAY;
- waxy polish without abrasive, For example, Golden Wax.
The first step is to rinse the surface Pemolux, Comet, Sorti or baking soda for degreasing. After removing the product, you need to dry the bath.
Next, the surface is polished fine-grained sandpaper or screwdriver with an abrasive wheel - zero, until leveling. When processing a scratch screwdriver the minimum speed is set.
The treatment area must be constantly damp to prevent cracks from appearing when heated. Therefore, during the entire stage of primary polishing, it is necessary to pour a thin stream of water onto the damage.
After the treated surface becomes smooth and matte, it is necessary to apply a granular polish. Treatment low abrasive the composition is applied vertically, then horizontally, until a smooth, uniform surface is obtained.
The final stage of eliminating minor scratches is finishing the coating. car polish with wax. Polishes containing wax, they have water-repellent properties and add a sparkling shine to any coating.
After obtaining a shiny surface, it must be washed with soapy water or non-aggressive liquid cleaning agent: Tersi, Oh yeah, Sarma. Immediately after this, the bath can be used.
Methods for eliminating chips and deep scratches
The enamel coating is subjected to mechanical stress, chips and deep scratches appear on the bowl, which expose the cast iron base.
Then the time comes to think about repairs, but not every owner knows how to restore the coating of a cast-iron bathtub with their own hands. And calling specialists will be expensive.
In fact, it is not difficult at all - you just need patience and perseverance. Next, we will look at options for resolving the problem and the procedure for performing the work.
Repair of chips is carried out in several ways:
- applying a porcelain patch;
- applying BF-2 glue and pigment filler;
- using automotive putty and enamel;
- spot filling of the chipped area.
Each method of restoring the coating is within the capabilities of any home craftsman. The durability of the patch depends on compliance with the instructions on the packaging of the installation material and on the quality of the preparatory work carried out.
If a chip or scratch formed a long time ago and the exposed metal has time to rust, the rusty deposits are removed. A powdered cleaner is suitable for this. Chistin Sanitary or Surzha. For deep rust penetration, oxalic acid can be used.
A significant layer of powder is applied to the chip site, which is moistened with a small amount of water until a paste forms. The latter is rubbed into the chip or scratch with a foam sponge.
The composition must be left for 15 minutes. Abrasive substances damage and weaken the enamel, so they are applied directly to the damaged area. After the time has passed, the bowl is washed with plenty of running water.
After treatment with an anti-corrosion substance and in the case of fresh chips, they begin to prepare the bath.
Work technology:
- The first stage involves cleaning and degreasing with baking soda or Pemolux. In the place where the enamel is damaged, more thorough treatment is carried out.
- After degreasing, the area is processed with a drill using a grinding stone or abrasive end attachments. Grinding a chip with an abrasive makes the inner surface of the damage rough, which improves the adhesion of materials.
- After abrasive treatment, the bowl must be washed and dried. For this, it is better to use a hair dryer, since forced drying guarantees complete evaporation of moisture from the treated coating.
- When the surface of the cast-iron bathtub is dry, you need to degrease the chipped area and the enamel around it. Thinner 646 or acetone is suitable for this purpose. Now you can begin priming and restoring the surface.
Grinding Deep scratches help align the edges, expand the groove, and create a microrelief for better adhesion. Good adhesion to materials can be ensured with a scratch width of at least 1 cm.
Method #1 - epoxy resin and porcelain
Repairing a cast iron bowl will require epoxy resin and porcelain cookware. Any broken cup or mug will do, the main thing is that the color of the dish matches the color of the enamel, then the camouflaged chip will not be noticeable. Before filling the chip, pieces of porcelain are ground into a fine powder.
First, a layer is applied to the surface of the chip epoxies, porcelain chips are poured onto it. If this is not enough to level the damage with the surface, then after 2.5 hours another layer of epoxy resin and porcelain powder is applied.
At the end of the time specified in the instructions, the fine-grained surface is finished polished sandpaper.
Method No. 2 - BF-2 glue
A rigid, heat-resistant, elastic, durable surface, instead of chipping on a cast iron bathtub, is formed by the polymer in the adhesive BF-2. To obtain a white mounting material, dry whitewash, chalk, and tooth powder are added to the transparent BF glue.
After preparing the two components, the glue and filler are thoroughly mixed and applied to the chip or scratch. This mixture dries within 24 hours, and the finished surface can be polished.
If one layer of glue is not enough to fill the chip, the next layer is applied after the previous one has completely dried, after 24 hours. When applying such a multi-level patch, polishing and using the bath is possible no earlier than after 72 hours.
Method No. 3 - automotive putty
Reliable do-it-yourself repair of a cast-iron bathtub is possible if you choose a high-quality water-repellent, heat-insulating primer, putty and enamel.
Such materials include automotive putty and auto enamel. In normal environments, materials experience significant stress, operate in conditions of high temperatures, humidity and vibration.
Therefore, a gentle climate in the bathroom will ensure minimal wear and tear on the materials. If the surface preparation technology and application technology are followed, the damage will be almost invisible.
Automotive waterproof putty is suitable for repairing chips and scratches. NOVOL Fiber, Body Soft. The material is applied to the prepared surface with a plastic or rubber spatula.
When filling damaged areas, it is necessary to ensure that there are no voids left under the putty layer. The surface of the patch should be smooth, without depressions.
If depressions have formed, then after the first layer has dried, it is necessary to apply the putty with a second one. If the coating is uneven, it should be smoothed with fine-grained sandpaper.
The treated surface can be painted over with automotive or two-component acrylic enamel, then the coating will be glossy and shiny.
Method No. 4 - restoration with enamel
Shallow, fresh chips and scratches can be repaired enamel for restoration. This method is the simplest, but does not ensure ideal surface leveling.If you sand with sandpaper and degrease immediately after the defect has formed, the enamel will last a long time.
Enamel restorer is sold in any plumbing store and is a tube or bottle with a brush filled with synthetic resin enamel.
Enamel for repairing scratches and chips is applied to the damaged surface in a thin layer. 4 hours after the first layer has dried, the paint is applied a second time. You can use the bathroom after 24 hours.
In addition, plumbing stores are filled with ready-made kits for restoring the coating and spot repairing the surface of bathtubs. Buyers are increasingly purchasing compositions for repairing cracks and scratches, chip removal kits, and aerosol enamels.
If yellowness cannot be removed from the surface of the bowl, or a network of small scratches has formed on the bathtub over time, then it is better to carry out not a local restoration, but complete painting.
Methods for restoring cracks
Cast iron bathing bowls have become popular due to their high wear resistance and durability. But even such durable products have defects in the form of enamel chips, corrosion or cracks.
The occurrence of a crack as a result of plumbing work or natural changes in water and air temperature becomes one of the reasons for replacing the bathtub. In some cases, it is possible to repair the defect.
Methods for eliminating a crack in a cast iron bathtub base: using cold welding, applying epoxy resin, soldering with lead-tin solder.
Option #1 - cold welding
At the first stage, the bath is degreased and cleaned Pemolux or soda. If there is rust around the edges and inside the crack, it is necessary to use a harsh abrasive such as Sanox or Chistin Sanitary.
The anti-corrosion agent is applied to the surface of the crack in a thick layer, wetted and left on the damage for 20 minutes. After washing off the cleaning agent, locking micro-holes with a diameter of 3 mm are drilled along the visible edges of the crack on one or both sides, depending on the location.
After degreasing, the surface is sanded with a grinder, electric drill with a grinding wheel or abrasive. Not only the crack is cleaned, but also the enamel around it, 1.5-2 cm wide.
A grinding wheel removes the coating right down to the metal. At the site of the crack, a hollow is ground out along the entire length of the fault.
After sanding, the tank coating is cleared of saw cuts and dirt. When the bathroom is dry, the crack area must be degreased with solvent, alcohol or cologne.
Hot water is poured into the bowl for half an hour, after it is drained, the surface is dried with a hairdryer. Now the treated coating defect can be covered by cold welding.
You can use the bath no earlier than after 24 hours. To even out the tone of the coating, the crack area can be painted with two-component acrylic or epoxy enamel.
Option #2 - epoxy resin
The process of preparing a surface for applying epoxy resin is practically no different from the technology for preparing a bath for applying cold welding.
Scheme of work:
- cleansing and degreasing;
- grinding and turning of grooves;
- additional degreasing.
After completing the preparatory work, it is necessary to prepare epoxy resin or putty based on epoxies. A layer of epoxy resin is applied to the crack site, fiberglass cloth is applied on top, and adhesive mounting material is applied again.
After the structure has dried, it is necessary to repeat the procedure: epoxy – fiberglass – epoxy. The result should be a patch above the enamel level; if not, then the procedure is repeated a third time.
After the patch has dried, 2 days after filling, the surface must be treated with fine-grained sandpaper and cover with enamel Stakryl or other durable paint.
Option #3 - soldering the crack
If you have soldering skills, you can solder a small crack in a cast iron bathtub. This requires thorough cleaning and freeing of the metal from the enamel.
Soldering is done with a 100-200-watt soldering iron using lead-tin solder and a special flux for steel and aluminum.
This method of solving a problem takes time and skill. The seam will not last long, but it will be suitable for temporarily fixing the problem.
To extend the attractiveness and life of your renovated bathtub, you need to properly choose a detergent. To clean the surface, do not use hard brushes, which can damage the smooth enamel.
Conclusions and useful video on the topic
For reliable adhesion of materials and durability of the coating, it is necessary to follow a clear sequence of preparatory and restoration work:
High-quality repair of a cast-iron bathtub means careful restoration of the most important plumbing fixture in the apartment.
Restoration of a damaged surface is possible as a result of the “jewelry” work of a master. The result of painstaking work and many hours of waiting will be a bath without visible chips, scratches and cracks, which will last for another ten years.
Share with readers your experience of restoring damaged enamel of a cast-iron bathtub and carrying out restoration work. Please leave comments, ask questions about the topic of the article and participate in discussions - the feedback form is located below.
Our bathtub is 20 years old, if not more. Of course, during this time it has become very worn and scratched, maybe because I constantly clean it with abrasives and a brush. I decided to restore it myself with glass acrylic, I sent my family to the dacha for the weekend because I couldn’t use the bathroom, and it was very smelly when applied. The main thing is to thoroughly clean the bathtub with sandpaper and then remove all the dust. You need to pour the glass carefully, although it tends to spread out a little. Naturally, it took a long time, but it was worth it. The bathtub looks like new.
It’s very good that ready-made bath restoration kits are now being sold with everything you need included. I, as a woman, don’t understand all this, but here everything is already ready, even with instructions. I bought this set with enamel, putty, even with a special stick for rubbing - instead of sandpaper. I did everything myself, it was absolutely easy.The bathtub looked like new.
I doubt that such a DIY repair will last for a long time. At best, you will have to repeat it in a year or a year and a half.
Hello. It all depends on:
— Quality of coating and materials.
— Operating conditions.
— Use of certain detergents.
- Water quality.
— Frequency of use.
— Properly keeping the device clean.
Any paint and any coating will require updating over time. Previously, wooden windows were painted with much less contact with moisture (internal frames), almost every year. Maybe not the best comparison, though.
Why such confidence? Personal experience? If you didn’t know, cast iron bathtubs still turn yellow after five years, no matter what you paint with. Isn’t it easier then to just buy an acrylic bathtub?
As for the fact that the enamel on cast iron bathtubs turns yellow after five years, this is already a well-known fact. In this case, the yellowness cannot be removed by any cleaning agents, since this effect comes from the oxidation of cast iron.
But this does not mean that the only optimal solution is to replace the cast-iron bathtub with an acrylic one. There are several alternative options that will help you update your bath and save your budget:
1. Filling a cast iron bathtub with acrylic. You will get a durable bathtub with an acrylic coating that will not yellow like enamel.
2. Installation of an acrylic bathtub in a cast iron one. Special acrylic bathtubs, which are made to match the size of cast iron ones, and are installed inside.
As you can see, you don’t have to buy a new bathtub; you can upgrade a cast-iron one with acrylic.
Hello. Acrylic bathtubs also have many disadvantages. As for yellowness, it is not the cast iron bathtub that turns yellow, but its coating due to use, water quality, and the use of unsuitable cleaning products. Acrylic also turns yellow, and the reason may be both the material itself and its coating.
After 5 years they still turn yellow - there is no such statistical time frame. She can stand as long as she likes and not turn yellow. depends on the quality of the coating, operation, washing, water and other factors. I had a cast iron bathtub for 10 years and it did not turn yellow with daily use. True, the coating was scratched here and there by children's toys.