Yellow glue is an essential adhesive for woodworking and DIY projects that requires a long-lasting bond, water resistance, and flexibility. However, choosing the right type of yellow glue for your project can be overwhelming, given the wide variety available on the market. In this comprehensive guide, we will explore the different types of yellow glue and their properties, uses, and application methods. We will also provide you with tips for using yellow glue and answer frequently asked questions to help you make an informed decision next time you embark on a woodworking project. So, let’s dive in and uncover the mysteries of yellow glue together!
Types of Yellow Glue
When it comes to woodworking, one of the most important factors to consider is the type of adhesive you use. Yellow glue, also known as carpenter’s glue, has become a popular option for its strength and durability. There are several types of yellow glue available on the market today. Understanding each type and its unique properties can help you determine which one is the best fit for your project. Let’s take a closer look at some of the most common types of yellow glue on the market today, including Aliphatic Resin Glue, Polyurethane Glue, and Modified PVA Glue.
Aliphatic Resin Glue
Aliphatic resin glue is also commonly known as yellow wood glue. It is a synthetic polymer adhesive that is commonly used in woodworking, carpentry, and general assembly applications. Aliphatic resin glue is very similar to traditional white glue or school glue, but it has stronger bonding properties.
Here are some key characteristics of aliphatic resin glue:
- It dries clear with a strong bond.
- It has a longer open time compared to other types of glue, which makes it easier to reposition items before the glue sets.
- It is water-soluble, making it easy to clean up with just warm water and soap.
- It has a high resistance to heat, making it suitable for use in environments where high temperatures are expected.
- It has a strong bond strength, making it suitable for use in applications that require a lot of strength, such as furniture and cabinetry construction.
Aliphatic resin glue is available in a variety of forms, including liquid, gel, and paste. The thicker forms are usually better for vertical applications where dripping or running may be a problem. Liquid aliphatic resin glue is more suited for horizontal applications where it is easier to spread. Sanding and staining can also easily be done over cured aliphatic resin glue.
Aliphatic resin glue is a versatile adhesive that is useful for many different applications in woodworking and other industries. It is an affordable, easy-to-use, and strong bonding solution that can be relied on for many different projects.
Polyurethane Glue
One type of yellow glue that is commonly used in woodworking is polyurethane glue. This type of glue is known for its superior bonding strength and water-resistant properties. It is also versatile and can be used on a wide variety of materials including wood, metal, ceramic, and plastic.
Benefits of Polyurethane Glue
– Provides superior bonding strength
– Has a longer working time compared to other adhesives
– Bonds well to a variety of materials including wood, metal, and plastic
– Water-resistant, making it ideal for outdoor use
– Can be used on both porous and non-porous surfaces
How Polyurethane Glue Works
Unlike other types of glue that dry through evaporation or oxidation, polyurethane glue cures through a chemical reaction. When the glue is exposed to moisture, typically found in the air or in the materials being bonded, it reacts with the moisture and expands to fill any gaps in the bond. The expansion helps to create a stronger bond and fills any voids that may exist.
Application Tips for Polyurethane Glue
– The surfaces being bonded should be clean and free of dirt, dust, and debris.
– Apply the glue to one surface only as the glue will expand and spread once applied.
– Clamp the two surfaces together firmly to ensure a strong bond.
– Allow the glue to cure for at least 24 hours before sanding or painting.
Concerns with Polyurethane Glue
While polyurethane glue is generally safe to use, it is important to follow the manufacturer’s instructions carefully and avoid skin contact. The glue can cause skin irritation and should be used in a well-ventilated area. Additionally, the glue can foam and expand, sometimes leading to excess glue dripping and potential messiness during the application process.
Polyurethane glue is a strong and versatile adhesive that is commonly used in woodworking and other applications. Its water-resistant properties and ability to bond to a variety of materials make it a popular choice for outdoor projects.
Modified PVA Glue
Modified PVA (polyvinyl acetate) glue is a water-based adhesive that has been modified to increase its strength and durability. It is a popular yellow glue that is commonly used for woodworking and carpentry projects where a strong bond is required. Modified PVA glue is an excellent alternative to traditional yellow glue due to its exceptional water resistance, high bonding strength, and heat resistance.
One of the key advantages of modified PVA glue is its water resistance. Unlike traditional yellow glue, modified PVA glue is highly water-resistant which makes it ideal for use in areas that are frequently exposed to water. It also withstands the negative effects that humidity can have on wood over time, making it a preferred adhesive for exterior carpentry and woodworking applications.
Another benefit of modified PVA glue is its high bonding strength. It creates a strong and durable bond that can handle stress and pressure. When the glue is applied correctly, it creates a bond that is as strong as the wood itself. Modified PVA glue exhibits excellent bonding properties due to its ability to penetrate the wood surface and create an intimate bond.
Modified PVA glue has a high temperature range, which allows it to withstand high temperatures without losing its grip. It can handle up to 150°F without losing its bonding properties, which is ideal for applications in high-temperature environments.
Here is a table highlighting the properties of modified PVA glue compared to traditional yellow glue:
| Properties | Modified PVA Glue | Traditional Yellow Glue |
|---|---|---|
| Water Resistance* | Excellent | Less water-resistant |
| Bonding Strength | High | Not as strong |
| Heat Resistance | High | Not as high |
*Modified PVA glue is also known as waterproof PVA glue.
Modified PVA glue is an excellent adhesive choice for woodworking and carpentry projects where high bonding strength and water resistance are required. Its superior bonding properties, water resistance, and high-temperature range make it an ideal adhesive for outdoor use as well as for use in high-temperature environments. So, if you are looking for a versatile and reliable adhesive, modified PVA glue stands out as a great option.
Properties and Uses of Yellow Glue
When it comes to woodworking, yellow glue is a reliable and popular choice of adhesive. Also known as carpenter’s glue or PVA glue, it comes in different types and offers various properties depending on the specific application. In this section, we’ll explore the unique properties and uses of yellow glue to help you choose the right type for your woodworking needs. From bond strength and durability to water resistance and temperature range, we’ll cover it all. But first, let’s take a closer look at the different types of yellow glue available in the market.
Bond Strength and Durability
Yellow glue is known for its excellent bond strength and durability. It creates a strong, permanent bond when applied correctly. The type of yellow glue used will impact its bonding strength and durability. Here are some common types of yellow glue:
- Aliphatic Resin Glue: This type of glue is known for its strong bonding strength and durability. It forms a strong bond with a wide range of surfaces, including wood, plastic, metal, and more.
- Polyurethane Glue: This glue is known for its superior bonding strength, especially on porous surfaces. It creates a strong bond that is resistant to water and heat.
- Modified PVA Glue: This glue is known for its strong bonding strength and quick drying time. It forms a strong bond with a variety of surfaces, including wood, cardboard, and more.
When using yellow glue, it is important to ensure that the surfaces being bonded are clean and dry. The glue should be applied evenly and allowed to dry completely before removing any clamps or pressure.
Yellow glue is highly regarded for its bonding strength and durability. It is commonly used in carpentry, woodworking, and other DIY projects. However, it is not recommended for use in areas where a waterproof bond is essential, as yellow glue is not completely waterproof.
Internal link: What is the viscosity of glue?
Water Resistance
When it comes to woodworking and carpentry projects, it is important to consider the potential exposure to moisture through water or humidity. This is where the water resistance properties of yellow glue come in handy.
Yellow glue is known for its great water resistance properties. It can withstand a certain amount of water exposure without losing its adhesive strength or causing the bonded joint to weaken.
To give you an idea of the water resistance levels of different types of yellow glue, here is a comparison table:
| Yellow Glue Type | Water Resistance |
|---|---|
| Aliphatic Resin Glue | Water-resistant |
| Polyurethane Glue | Waterproof |
| Modified PVA Glue | Water-resistant |
Aliphatic resin glue is commonly used in woodworking projects where water exposure is a concern, such as outdoor furniture. This type of glue is known for its good water-resistance properties, but it is not completely waterproof.
Polyurethane glue is the most water-resistant type of yellow glue available. It is waterproof and is suitable for projects that are exposed to frequent or prolonged water exposure, such as boats or outdoor structures.
Modified PVA glue, also known as cross-linking PVA glue, is a water-resistant glue that is suitable for projects that may be occasionally exposed to moisture, such as picture frames or bookshelves.
It’s important to note that the degree of water resistance can vary based on the application technique and the amount of glue used. It is always best to follow the manufacturer’s instructions for the specific type of glue you are using to ensure maximum water resistance.
If you are concerned about how to handle and work with glue, you can check out our article about is super glue toxic when dry or what if you eat super glue for more information.
Open Time and Clamping Time
Open time and clamping time are important properties to consider while working with yellow glue. Open time refers to the amount of time until the glue starts to set. During this time, one can still manipulate and adjust the position of the pieces being glued, which is especially useful for large or intricate projects. Clamping time, on the other hand, refers to the amount of time for which the glued pieces need to be held under pressure to ensure proper bonding.
Different types of yellow glue have different open and clamping times. The table below summarizes the open and clamping times of the three most commonly used types of yellow glue: aliphatic resin glue, polyurethane glue, and modified PVA glue.
| Type of Yellow Glue | Open Time | Clamping Time |
|---|---|---|
| Aliphatic Resin Glue | 5-10 minutes | 30-60 minutes |
| Polyurethane Glue | 15-30 minutes | 1-6 hours |
| Modified PVA Glue | 5-15 minutes | 30-60 minutes |
It is important to note that open and clamping times depend on various factors such as temperature, humidity, and the type of surfaces being bonded. Higher temperatures and lower humidity can reduce open and clamping times, while lower temperatures and higher humidity can increase them.
To maximize bonding strength, it is recommended to adhere to the recommended open and clamping times of the chosen yellow glue. This can ensure that the glue has enough time to penetrate and bond the surfaces properly. If glue is not clamped for the recommended time, it can result in poor bonding and weakened strength.
It is also important to note that if the glue is not used within its open time, it may start to set and lose its ability to bond properly. Conversely, if the glue is clamped for longer than the recommended time, it can result in over-drying and weakened strength.
Understanding the open and clamping times of yellow glue can help ensure that projects are properly bonded and durable.
Temperature Range
When choosing a yellow glue, it is important to consider its temperature range to ensure that it remains stable and effective in various conditions. Most types of yellow glue can function well within a temperature range of 50°F to 70°F (10°C to 21°C). However, some specialized yellow glues can withstand higher temperatures.
Aliphatic Resin Glue – This type of yellow glue performs well in moderate temperature ranges and can maintain its bonding strength up to 150°F (66°C). It can also function properly in extreme cold temperatures up to 30°F (-1°C).
Polyurethane Glue – Polyurethane glue can withstand temperatures up to 200°F (93°C) and still retain its bond strength. It remains stable even in cold temperatures as low as 0°F (-18°C).
Modified PVA Glue – Modified PVA glue has a temperature resistance of up to 130°F (54°C). It can still function in mild to moderate cold temperatures.
It is important to keep in mind that excessive heat can cause a yellow glue to lose its bonding strength. Thus, it is essential to store yellow glue in a cool and dry place to preserve its strength and effectiveness.
It is not recommended to use yellow glue in extreme temperatures, as it may affect the strength and bonding of the materials. In case of doubt, testing the materials’ bonding strength at different temperatures can help ensure the glue’s effectiveness.
Maintaining the temperature range of a yellow glue is crucial for its effective use in bonding materials. It is best to adhere to the manufacturer’s recommendations when selecting and using a yellow glue, depending on the temperature range needed for the application.
Application Areas
Yellow glue is an incredibly versatile adhesive that finds various applications in different industries. Some of the most common applications areas of yellow glue are:
- Woodworking: Yellow glue is most commonly used as a woodworking adhesive since it provides a strong bond and dries clear. It is an excellent choice for bonding wood, veneer, and laminates. Whether you are working on a DIY project or a professional woodworker, yellow glue is an essential tool in your arsenal.
- Paper and Cardboard: Yellow glue is frequently used in the paper and cardboard industries because it dries clear and offers a strong bond. It can be used to bond paper, cardboard, and other paper-based materials. It is also ideal for making paper mache and other paper-based crafts.
- Construction: Yellow glue is used in the construction industry for bonding materials such as drywall, paneling, and molding. It is water-resistant, making it an ideal choice for outdoor projects such as decks and fences.
- Automotive: Yellow glue is used extensively in the automotive industry for repairing and bonding interior components such as fabric and upholstery. It is also useful for bonding plastic and metal components such as door panels.
- Textile: Yellow glue is used in the textile industry for bonding fabrics such as cotton, silk, and wool. It can be used to bond seams and hems, as well as to attach patches.
Yellow glue has a wide range of applications, and its excellent bonding properties make it a popular choice across various industries. Whether you are a woodworker, a paper crafter, or a DIY enthusiast, yellow glue is an asset in your toolkit. It’s no wonder that yellow glue is a popular choice among professionals and hobbyists alike.
If you’re interested in learning more about the different types of glue, check out our articles on horse glue, nerve glue, and school glue. If you want to know how to get the most out of your super glue, be sure to read our article on how long super glue lasts and how to open a glue tube. Additionally, if you are interested in printing techniques, read up on glue printing and if you’re curious about the origins of slime, check out our article on who invented slime with glue.
How to Use Yellow Glue?
When it comes to woodworking and carpentry, Yellow Glue is a popular choice due to its strong bonding properties. However, improper use of the glue can lead to a weak bond or even damage to the project. In this section, we will guide you through the correct steps for using Yellow Glue to ensure successful and long-lasting results. From surface preparation to drying time, we will cover everything you need to know to achieve the best results using Yellow Glue. So, let’s get started!
Surface Preparation
The success of any woodworking project depends on the quality of the bond between two pieces of wood. To ensure a strong and durable bond, proper surface preparation is crucial. Here are some steps you need to follow for effective surface preparation:
| Step | Description |
|---|---|
| 1 | Clean the Surface Ensure that the surfaces to be joined are clean, dry, and free from any dust, grease, or debris. Use a clean cloth or a brush to clean the surface thoroughly. |
| 2 | Eliminate Sawdust Sawdust and woodworking debris can interfere with the adhesion process. To eliminate sawdust, use a vacuum cleaner or air compressor. You can also use a tack cloth or a brush to remove sawdust. |
| 3 | Apply Pressure Before gluing, ensure that the wood pieces fit perfectly. Apply pressure using a clamp, or use masking tape for small pieces. Applying pressure ensures that the pieces stick together firmly. |
| 4 | Sand the Surface Sanding the surface before applying yellow glue is crucial. Use sandpaper to smoothen the surface, and remove any rough spots. Sanding increases the surface area, which improves the bond between the two pieces of wood. |
| 5 | Apply Glue Evenly Apply yellow glue evenly on one of the surfaces to be joined. Use a brush, spatula, or roller to apply the glue uniformly. Be careful not to apply too much as excess glue can interfere with the bond. |
| 6 | Join the Wood Pieces Join the wood pieces immediately after applying the glue. Press the pieces together firmly, ensuring that they are aligned correctly. |
| 7 | Clean up the Excess Glue Use a damp cloth to clean up any excess glue that seeps out of the joint. Leaving excess glue can compromise the finish of your woodworking project, and interfere with the bond. |
Following these steps will ensure that you get a strong and durable bond that will last for a long time. Proper surface preparation is essential when using yellow glue or any other type of adhesive.
Application Methods
When it comes to applying yellow glue, there are different methods that can be used depending on the specific project. Here are some common application methods:
- Brush application: This method involves using a brush to apply the glue onto the surface that needs to be bonded. It works well for larger surfaces that require more coverage. When using a brush, be sure to apply an even coat and avoid leaving any excess glue on the surface.
- Roller application: This method is similar to brush application, but it uses a roller instead. Rollers can be useful for applying glue to larger surfaces quickly and efficiently. Just like with brush application, it’s important to apply an even coat and avoid excess glue.
- Drip application: For smaller projects or areas that are difficult to reach, drip application can be a good choice. This involves applying small drops of glue to the surface using a dropper or similar tool. Be sure to distribute the drops evenly and avoid excess glue.
- Spray application: Spray application involves using a spray gun to distribute the glue over the surface. It can be useful for covering large areas quickly, but it may not be suitable for all projects. This method requires skill and experience in order to apply an even coat and avoid overspray.
No matter which application method is used, it’s important to follow the manufacturer’s instructions for the specific type of yellow glue being used. This will ensure the best results in terms of bond strength and durability. Additionally, it’s important to wear protective gear, such as gloves and eye protection, when working with glue in order to avoid skin and eye contact.
Clamping and Drying Time
When using yellow glue, it is important to allow sufficient clamping and drying time to ensure a strong bond. The exact clamping and drying time will depend on the type of yellow glue being used and the specific application.
Clamping Time:
– Aliphatic resin glue typically requires a clamping time of 30 minutes to 1 hour.
– Polyurethane glue may require a longer clamping time of up to 4 hours.
– Modified PVA glue usually requires a clamping time of 15 to 30 minutes.
During the clamping time, it is important to apply even pressure to the glued surfaces. This can be achieved through the use of clamps or other suitable tools.
Drying Time:
– Aliphatic resin glue usually dries within 24 hours.
– Polyurethane glue can take anywhere from 4 to 24 hours to dry, depending on the humidity and temperature.
– Modified PVA glue dries faster, often within 20 to 30 minutes.
It is important to give the glue sufficient time to dry completely before sanding or applying any finish. Rushing this process can lead to a weaker bond or other issues.
In general, it is best to follow the manufacturer’s recommendations for clamping and drying time to ensure the strongest possible bond.
Tips for Using Yellow Glue
When using yellow glue, there are few tips that can help ensure a successful and strong bond.
Tip 1: Use the right type of yellow glue for your project. As mentioned earlier, there are different types of yellow glue suited for different applications. Make sure to choose the right one for your project by considering the surface materials, weather conditions, and curing time.
Tip 2: Don’t squeeze too much glue. Yellow glue expands slightly during the drying process, so avoid using too much glue as it can create excessive foaming and overfilling. A thin and even layer of glue is enough to create a strong bond.
Tip 3: Apply pressure and clamp the glued parts. The glue needs to be squeezed into the pores of the surface materials to create a strong bond. Applying pressure and clamping the glued parts together for the recommended drying time can help ensure a strong and durable bond.
Tip 4: Keep excess glue off the surface. Excess glue on the surface can interfere with staining, painting, or finishing the project. Wipe or sand off any excess glue before it dries or use a damp cloth to clean the surface.
Tip 5: Store the glue properly. Yellow glue should be stored in a cool and dry place, away from direct sunlight, extreme heat, or moisture. Always keep the bottle tightly closed to prevent the glue from drying out or spoiling.
By following these tips, you can ensure that your yellow glue projects are successful and durable, while avoiding common mistakes and issues that may compromise the effectiveness of the glue.
FAQs on Yellow Glue
As you begin to delve into the world of yellow glue, you may have some questions about its properties and use. To help address some of the most common inquiries, we’ve compiled a list of frequently asked questions and their answers below. From its waterproof capabilities to its drying time, there’s no need to be perplexed any longer. Let’s dive in and learn more.
What is yellow glue used for?
Yellow glue is a versatile adhesive that can be used for a variety of purposes. It is commonly used in woodworking and construction projects. Here are a few examples of what yellow glue can be used for:
- Bonding wood: Yellow glue is often used to bond wood pieces together. It creates a strong, durable bond that can withstand a lot of stress and strain. Whether you are building a piece of furniture or repairing a broken wooden object, yellow glue can be a good choice.
- Cabinet making: Cabinets and other furniture pieces are often made with yellow glue. Its ability to bond wood and resist water make it an ideal choice for these types of applications.
- Veneering: Yellow glue can be used to apply veneers to wooden surfaces. Its ability to create a strong bond without staining the wood makes it a popular choice in veneering applications.
- Repair work: Yellow glue can be used to repair a variety of objects. Whether you need to fix a broken dish or repair a piece of furniture, yellow glue can create a strong and lasting bond.
No matter what you are using yellow glue for, it is important to follow the manufacturer’s instructions to ensure the best possible results.
Is yellow glue waterproof?
Yellow glue is known for its water-resistance, making it a popular choice in woodworking and other outdoor applications. However, it’s essential to understand that not all types of yellow glue are completely waterproof.
Types of Yellow Glue that are Waterproof:
- Polyurethane glue is known for its superior water resistance. It’s perfect for outdoor applications that require a strong and long-lasting bond.
- Modified PVA glue is also water-resistant, but it’s not as strong as polyurethane glue. It’s best used for indoor projects that may be exposed to moisture.
Types of Yellow Glue that are not Waterproof:
- Aliphatic resin glue is not recommended for outdoor use or any application that may be exposed to water. It’s best used for indoor projects only.
It’s worth noting that even water-resistant yellow glue may lose its adhesive properties over time when it’s exposed to constant moisture. If you need a completely waterproof bond, it’s best to use an epoxy adhesive.
So, while yellow glue may have some water-resistant properties, it’s essential to select the right type of yellow glue for your project to ensure that it can withstand exposure to moisture and water.
How long does yellow glue take to dry?
The drying time for yellow glue varies depending on the type of glue and environmental conditions. Typically, yellow glue requires around 24 hours to dry completely. However, you will be able to handle the glued objects within a few hours after applying the glue.
Factors affecting drying time:
- Humidity: A humid environment can cause yellow glue to dry slower than usual.
- Temperature: High temperature can speed up the drying process, while low temperature can prolong the drying time.
- Amount of glue applied: Applying too much glue to the surfaces can increase the drying time.
- Surface material: The type of surface material you are gluing can affect the drying time as well.
It’s essential to give the glue sufficient time to dry completely before removing the clamps or using the glued item. If the glue is not entirely cured, it may affect the strength of the bond and lead to failure in the future.
If you are in a rush and need to reduce the drying time, you can use a fan or blower to decrease the humidity level and speed up the drying process. However, it’s essential to avoid applying pressure or moving the glued object before the glue is completely dry.
The drying time for yellow glue varies based on several factors, including humidity, temperature, amount of glue applied, and surface material. To ensure a strong and durable bond, it’s crucial to give the glue sufficient time to dry completely before handling the glued object.
Conclusion
After learning about yellow glue, it is clear that it is a versatile adhesive that offers a variety of benefits and can be used for a range of projects. Its ability to bond quickly and create strong, durable connections makes it an excellent choice for woodworking, furniture making, and other DIY activities.
Whether you need a waterproof glue for outdoor projects or a versatile adhesive for household repairs, yellow glue has got you covered. From its different types to its various properties and applications, this comprehensive guide has covered all you need to know about yellow glue.
To get the most out of your yellow glue, it is essential to follow the recommended surface preparation, application methods, and clamping and drying times. By doing so, you’ll ensure a strong, long-lasting bond that can withstand extreme temperatures, moisture, and other environmental factors.
In conclusion, the key to successful bonding with yellow glue is to select the right type for your project and use it correctly. With the information covered in this guide, you can confidently choose the right yellow glue for your needs and create high-quality, durable connections. Happy crafting and DIYing!
Frequently Asked Questions
What makes yellow glue different from other types of glue?
Yellow glue, also known as woodworking glue, is specifically designed for woodworking projects. It is known for its strong bonding properties, water resistance, and longer drying time compared to other glue types.
What are the different types of yellow glue available in the market?
There are mainly three types of yellow glue available: aliphatic resin glue, polyurethane glue, and modified PVA glue. Each type has its own unique properties and uses.
How do I choose the right yellow glue for my woodworking project?
You should consider the specific needs of your project, such as the required bonding strength, water resistance, and drying time. You should also consult with experts or refer to the manufacturer’s instructions to determine which type of yellow glue is best suited for your project.
What is the bond strength and durability of yellow glue?
Yellow glue is known for its strong bonding properties and high durability. It creates a strong bond between two surfaces and remains bonded even under heavy stress or strain.
Is yellow glue water-resistant?
Yes, yellow glue is water-resistant, which makes it suitable for use in outdoor projects or in areas that are exposed to moisture.
What is the open time and clamping time of yellow glue?
The open time of yellow glue is the amount of time you have to work with it before it starts to set. Clamping time refers to the time required for the glue to dry and form a strong bond. The open time and clamping time of yellow glue vary depending on the type of glue used.
What is the temperature range for using yellow glue?
Yellow glue is typically used at room temperature, which is around 68 to 77 degrees Fahrenheit. However, this may vary depending on the type of glue used and the manufacturer’s recommendations.
What are some common application areas for yellow glue?
Yellow glue is commonly used in woodworking projects, such as furniture making, cabinet making, and joinery. It is also used in construction projects, such as framing and paneling.
How should I prepare the surface before applying yellow glue?
You should ensure that the surfaces to be bonded are clean, dry, and free from any dirt, dust, or debris. It is also recommended to roughen the surfaces slightly using sandpaper to ensure a better bond.
The drying time of yellow glue varies depending on the type of glue used, the relative humidity, and the temperature. Typically, it takes between 30 minutes to 24 hours for the glue to dry completely.