How to cut polystyrene molding: practical guide

Working with interior decorative elements requires not only artistic taste but also technical skills. Especially this applies to such a delicate material as polystyrene. How to cut polystyrene molding - a question that concerns anyone who decided to independently transform the space of their home. This lightweight and practical material has gained popularity due to its ease of installation and affordable price, but improper approach to cutting may ruin the entire work and turn elegantPolystyrene moldinginto messy scraps with jagged edges.

PVC moldings open up endless possibilities for decorating walls, ceilings, doorways, and furniture. They are used to create classic interiors, divide space into zones, and conceal joints and irregularities. But all this beauty depends on one key moment — precise cutting. The final result — perfect joints without gaps or disappointing gaps requiring spackling — depends entirely on how accurately and cleanly you cut the profile.

In this detailed guide, we will cover all aspects of working with PVC moldings: from selecting the right tool to the nuances of finishing. You will learn professional secrets that will help you avoid typical mistakes and achieve results that match those of experienced craftsmen.

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Tools for Cutting PVC Moldings

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Miter Box — the Foundation of Accurate Cutting

A miter box is an indispensable assistant when working with any decorative profiles. This simple yet ingenious tool consists of a tray with guide slots arranged at specific angles. For quality cutting of moldings, a miter box is as essential as air — it ensures a perfectly straight cut at the required angle.

Professional miter boxes are made from impact-resistant plastic or aluminum. They feature adjustable guides allowing any angle from 0 to 180 degrees. For home use, a standard miter box with fixed slots at 45, 60, and 90 degrees is sufficient. The 45-degree angle is most commonly used wheninstalling moldingsin room corners.

When choosing a miter box, pay attention to its dimensions. The width of the tray should match the size of your molding — the profile must fit snugly into the slot without deforming. The depth of the miter box also matters: a shallow one won’t hold a large molding, while an overly deep one will make work difficult. The optimal depth is around 50–70 mm for standard wall profiles.

A quality miter box should have clamping elements or jaws to secure the workpiece during cutting. This is critically important for achieving a clean cut without material displacement. Some models come with rulers and protractors, which simplify marking and allow for high precision.

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Fine-Toothed Saw

Choosing the right saw for cutting PVC moldings determines half the success. Large saw teeth tear soft material, leaving rough edges and chips. Therefore, the main rule — the finer the teeth, the cleaner the cut. A metal-cutting saw with fine, frequent teeth or a specialized plastic saw is ideal.

The saw blade should be thin and flexible, yet rigid enough to not bend during use. A too-thick blade creates a wide cut and may deform thin-walled moldings. The optimal blade thickness is 0.5–0.8 mm. Pay attention to the blade’s tooth set — it should be minimal to achieve the narrowest possible cut.

The blade length is chosen based on the molding’s width. For standard profiles up to 100 mm wide, a 250–300 mm saw blade is suitable. It’s important that as many teeth as possible engage during each saw stroke — this ensures a smooth, clean cut without jerking.

The saw handle should fit comfortably in the hand and provide a secure grip. Professionals recommend models with rubberized grips that won’t slip even on wet hands. The angle between the handle and blade affects ease of use in the miter box — a slight incline is optimal, allowing natural handling without wrist strain.

Sharp Blade and Pencil Knife

For thin moldings and finishing edge trimming, a sharp pencil knife or special blade is indispensable. This tool allows for precise trimming, removing burrs, and correcting minor irregularities. The key condition — the blade must be absolutely sharp. A dull knife doesn’t cut polystyrene but crushes it, creating ragged edges and deformations.

wall molding polystyreneThin moldings can be cut exclusively with a sharp blade without using a saw. For this, use the technique of multiple shallow cuts: first, make a shallow cut along the marked line, then gradually deepen it until the blade passes through the entire profile. This method yields a perfectly smooth cut without chips.

Professional installers often use replaceable blades for construction knives. These blades are made from high-carbon steel, hold their edge longer than standard pencil knives, and allow cutting at a greater angle. It’s important to regularly replace dull blades — even a slight loss of sharpness significantly degrades cut quality.

For safe operation, choose knives with blade locks and ergonomic handles. The blade must be securely fastened and not protrude unintentionally. Professional models feature metal bodies and quick-blade replacement systems, saving time during large-scale projects.

Additional Tools

In addition to primary cutting tools, quality work requires auxiliary tools. A ruler or tape measure is necessary for accurate measurements. Use a metal ruler at least 1 meter long — it won’t deform and allows drawing long straight lines during marking.

The marking pencil should be sufficiently hard (2H or 3H) to produce thin, clear lines. Soft pencils leave wide, blurry marks that complicate precise cutting. Some craftsmen prefer a fine marker, but it must not contain solvents that could damage polystyrene.

A speed square is necessary to check the perpendicularity of cuts and mark right angles. A level will help when fitting moldings to walls. Fine-grit sandpaper (P180–P240) is useful for final sanding of ends and removing minor irregularities.

Correct Cutting Angle for Moldings

Understanding Angles in the Room

Before cutting, you must accurately determine the angles in the room. Perfect 90-degree angles are rare — most angles have slight deviations. These deviations can range from a few millimeters to a centimeter, and they must be accounted for during cutting. Use a protractor or construction speed square to measure the actual angle.

If the room’s angle is exactly 90 degrees, each molding should be cut at a 45-degree angle. When joining two such cuts, you get a perfect fit without gaps. However, if the angle differs from 90 degrees, you must adjust the cutting angle. For an acute angle (less than 90 degrees), cut each piece at an angle less than 45 degrees; for an obtuse angle (more than 90 degrees), cut at an angle greater than 45 degrees.

A professional approach involves making a template from cardboard or thin plastic. Cut two strips the width of your molding and join them at the corner, precisely replicating the wall’s configuration. Then transfer the resulting angle to the miter box or use an adjustable miter box, setting it to the required angle.

Cutting Internal Angles

Internal angles - the most common case wheninstalling moldingon walls. To create a neat internal angle, place the molding in the miter box with the front side up. The edge that will be against the wall should rest against the back wall of the miter box.

The first molding is cut from right to left at a 45-degree angle, with the cutting direction from left to right, top to bottom. The second molding is cut mirror-image: from left to right, with the cutting direction from right to left, top to bottom. With proper cutting, the ends of the moldings will fit perfectly, forming a right angle.

An important detail - the position of the molding in the miter box must exactly match its position on the wall. If the molding is to be mounted under the ceiling, the bottom edge of the profile rests on the bottom of the miter box. If it's a wall molding mounted at eye level, press it against the back wall of the miter box with the side that will contact the wall.

A common mistake for beginners - incorrect orientation of the molding in the miter box. Before cutting, always check the profile's position, visualizing how it will be installed on the wall. You can even mark the molding with indicators for top and bottom to avoid orientation errors.

Cutting External Corners

External angles require the opposite approach. Here, the molding is also placed in the miter box with the front side up, but the cutting angles are reversed. The first molding is cut from left to right, with the cutting direction from right to left, top to bottom. The second is cut from right to left, with the cutting direction from left to right, top to bottom.

When working with external angles, precision is especially important. Even the slightest deviation will result in noticeable gaps that are hard to mask. It is recommended to first make a test cut on small pieces of molding to ensure the correct miter box setup and cutting technique.

Polystyrene impact-resistant wall moldingThe material's denser structure makes it easier to cut precisely. It chips less and deforms less under saw blade pressure. However, the principles of operation remain the same - the main thing is to maintain the angle and cutting direction.

For external angles, preliminary fitting is critically important. After cutting, place both moldings at the angle and check the fit quality. If there are minor gaps, they can be corrected with fine sandpaper or a sharp blade, carefully trimming protruding parts.

Straight Cuts

Straight cuts at 90 degrees are necessary when joining moldings on long wall sections or when creating frames and decorative compositions. For a straight cut, the molding is placed in the miter box perpendicular to the guides, and the saw passes through the slot positioned at a 90-degree angle.

A straight cut may seem simple, but it requires special attention to perpendicularity. Even a slight tilt of the saw blade will result in a slanted cut, and when joining two moldings, a noticeable gap will form. Use a construction square to check the quality of the cut.

When creating decorative frames fromwall molding polystyrene impact-resistantall four corners are cut at 45 degrees, and the joints of long sides require perfectly perpendicular cuts. Only in this way can you achieve a visually seamless structure without visible joints.

Preventing chips and deformations

Preparing molding for cutting

The quality of the cut directly depends on the preparation of the material. Before work, the molding must acclimate in the room. If the profile was stored in a cold room or outdoors, bring it into the room at least one day before starting work. Cold polystyrene is more brittle and prone to cracking during cutting.

Inspect the molding for defects. Minor dents or deformations can be corrected by gently heating the defective area with a hairdryer and shaping it to the desired form. However, this should be done extremely carefully - overheating destroys the material's structure. The temperature should be minimal, sufficient only to soften the polystyrene.

Clean the molding surface from dust and dirt before cutting. Even small sand particles can cause chips as the saw passes over them. Use a soft dry cloth or brush. Do not use wet cleaning - moisture can be absorbed by the porous material and cause deformation.

Mark the cutting line with a thin pencil or marker. The line should be clear and visible, but not wide. When cutting, the saw must follow precisely along the outer edge of the marking line, leaving it on the cut piece. This compensates for the saw kerf and ensures the exact length of the finished part.

Cutting technique without chips

The main cause of chips is improper saw movement. Sudden jerks, excessive pressure, and uneven speed destroy the material's structure. Proper technique involves smooth, even movements with moderate pressure. The saw should do the work, not you - let the teeth cut the material, guiding the tool only.

Start cutting with light, short movements, creating a guiding groove. The first 5-10 movements should be slow, until the saw penetrates the material by 2-3 mm. Then you can increase the amplitude of movements, but maintain smoothness. Use the full length of the blade - this ensures even cutting and reduces load on each tooth.

When cuttingmolding polystyrene to the wallit is important to control the saw's angle. It must move strictly in the plane of the cut, without deviation left or right. Side pressure causes deformation of the thin-walled profile and results in a slanted cut. Hold the saw relaxed but firmly, controlling the direction of movement.

Finish the cut especially carefully. When only the last millimeter of material remains, reduce the speed of movement and pressure. A sudden pass of the saw through the final section often results in a chip of the molding coming out. The final movements should be as smooth and controlled as possible.

Working with Thin-Walled Profiles

Thin-profile moldings are especially sensitive to pressure and require careful handling. When placing them in a miter saw, do not clamp them too tightly—excessive pressure will deform the profile. The molding should fit snugly against the saw’s walls but not be crushed.

For cutting thin-profile moldings, use the finest-toothed saw blade or a sharp blade. The multiple-cut technique works best: first, score the front surface of the molding to a depth of 1–2 mm, then gradually deepen the cut in 3–4 passes. This approach prevents deformation and chipping.

Some professionals use painter’s tape to protect the molding surface at the cut line. Apply a strip of tape along both sides of the profile along the marked line. This reinforces the material and prevents polystyrene from delaminating during sawing. After cutting, the tape can be easily removed without leaving residue.

Preventing Material Melting

Polystyrene is a thermoplastic material that can melt from friction. Fast saw movements generate heat, and the cut edges melt, becoming uneven and bumpy. To avoid this, control the cutting speed—movements should be steady and unhurried.

If you notice the material beginning to melt (cut edges become glossy and sticky), stop and allow the molding to cool. You can gently blow air on the cut area or wipe it with a damp cloth. After cooling, continue working, reducing the saw’s movement speed.

Using power tools (e.g., a jigsaw) increases the risk of melting significantly. High-speed blade movement generates substantial heat. If you still decide to use a power tool, choose the lowest speed and use blades with large gullets designed for plastic. However, manual cutting is preferable for quality work.

Safety When Working with Moldings

Protecting Hands and Eyes

Working with cutting tools always carries a risk of injury. Even a seemingly harmless office knife can cause serious cuts. Always wear protective gloves when cutting moldings. Choose gloves made of dense fabric or leather that protect against cuts while maintaining fingertip sensitivity.

Safety glasses are mandatory during work. Small polystyrene particles can fly off during cutting and enter the eyes. This is not only unpleasant but also dangerous—sharp fragments can damage the cornea. Use tightly fitting glasses that fully cover the eyes on all sides. Ordinary prescription glasses do not provide sufficient protection.

When working with a sharp blade, follow the basic rule—cut away from yourself, never toward yourself. Hold the hand with the knife so that if the blade slips, it moves away from your body. Keep your other hand behind the cut line, not in front of it. Never direct the blade toward any part of your body.

Work area organization

Safety begins with proper organization of the work area. The workbench or table must be stable and at a comfortable height. Working in an uncomfortable posture leads to rapid fatigue and loss of concentration, increasing the risk of injury. The optimal work surface height is at waist level or slightly below.

Ensure good lighting. Poor visibility forces you to strain your eyes and lean closer to the cut area, which is dangerous. Use a bright lamp directed at the work zone, or work under daylight. Avoid harsh shadows—they distort depth perception and can lead to inaccurate cuts.

The work area must be clean and free of unnecessary objects. Clear the table of everything unnecessary—tools not currently in use, molding scraps, packaging materials. Clutter distracts attention and can lead to accidents. Keep cutting tools in designated holders or at a safe distance from the table’s edge.

Working with Tools

Before starting work, inspect the condition of your tools. Handles must not have cracks or chips, and fastenings must be secure. Worn or damaged tools may break during use and cause injury. Pay special attention to the miter saw—cracks in the body can lead to its failure under load.

Cutting tools must be sharp. Ironically, a dull blade is more dangerous than a sharp one. Using a dull blade requires more force, and if the tool slips, the impact force will be significantly higher. A sharp blade cuts easily and controllably, while a dull blade requires pressure and may slip unpredictably.

Securely clamp the molding when working in a miter saw. If the profile shifts during cutting, the saw blade may slip and injure your hand. Use clamps or vises to secure the miter saw to the table. This is especially important when working with long moldings, which create significant leverage and may tip over an unsecured miter saw.

Protecting Respiratory Tract

Cutting polystyrene produces fine dust that can irritate the respiratory tract. Although polystyrene is considered relatively safe, prolonged inhalation of dust is undesirable. Use a respirator or medical mask during large-scale work. This is especially important for individuals prone to allergies or with respiratory issues.

Work in a well-ventilated space. Open windows or use a fan to create airflow. This not only ensures fresh air circulation but also reduces dust concentration in the breathing zone. If working in an enclosed space without ventilation, take regular breaks and step outside for fresh air.

After finishing work, thoroughly clean the work area. Do not blow dust—it will stir it into the air. Use a damp cloth to collect fine particles or a vacuum cleaner with a good filter. Polystyrene dust is light and can remain suspended in the air for a long time, so it must be mechanically collected, not simply swept away with a broom.

Cleaning and Final Processing of Cuts

Removing Flash

After cutting, small irregularities, flash, and roughness inevitably remain on the ends of moldings. These defects are especially noticeable at corners and can prevent profiles from fitting tightly together. The first step in final processing is removing flash with a sharp blade or fine-grit sandpaper.

Work carefully, removing only protruding parts. Do not attempt to alter the cut shape—the goal is merely to smooth irregularities. Hold the blade at a slight angle to the surface and guide it along the edge, shaving off thin shavings. Movements should be light and controlled.

Sandpaper with grit P180–P240 is ideal for final processing. Coarser paper leaves deep scratches, while finer paper cannot effectively remove flash. Wrap a small piece of sandpaper around a block or fold it into multiple layers. Sand the end gently with light movements, applying minimal pressure.

If you purchase {name} of high quality, flash will be minimal, but final processing is still necessary for an ideal result.Polystyrene moldinghigh quality, burrs will be minimal, but final finishing is still necessary for an ideal result.

End Face Alignment

Even with careful cutting, moldings' ends may have minor irregularities. To smooth them, use fine sandpaper mounted on a flat surface. Place the sandpaper on a table or another rigid plane and gently sand the molding's end in circular motions.

It is important to maintain the cut angle. Do not tilt the molding while sanding—keep it perpendicular to the sandpaper. Periodically check perpendicularity with a square. Even slight deviations from a right angle will become noticeable when joining moldings.

For aligning ends of long moldings, use a special sanding board. Stretch sandpaper over a flat wooden board and secure it. This tool allows processing ends with a constant angle and even pressure.

After sanding, check the joint quality. Align two moldings at the required angle. There should be no gaps or misalignments between them. If minor discrepancies exist, sand the problematic areas. For precise fitting, use a blade to shave off the thinnest shavings from protruding areas.

Dust Removal

After all manipulations, moldings must be thoroughly cleaned of dust. Polystyrene dust is electrostatic and adheres to surfaces. If you glue a dusty molding, particles will remain underneath, creating unevenness and reducing adhesive bond quality.

Use a soft, wide brush to remove dust from the surface and ends of moldings. Brush along the profile, not across it, to avoid trapping dust in relief. Pay special attention to grooves and decorative elements, where dust accumulates most.

For final cleaning, use a slightly damp cloth. Wipe the molding with gentle motions, without pressing hard. The moisture should be minimal—the cloth should be nearly dry, only slightly damp. After damp cleaning, allow the molding to dry completely before installation.

Some masters use a vacuum cleaner with a soft nozzle to remove dust. This is an effective method, but work carefully—strong suction may damage delicate decorative elements on the molding.Polystyrene molding for wall installation.

Dry Fit

Before final installation, perform a dry fit. Attach prepared moldings to the wall without adhesive and check the joint quality. This is your last chance to detect and correct defects before the molding is fixed.

During fitting, pay attention to several aspects. Angles must fit tightly, without gaps. The molding must contact the wall along its entire length—lack of contact in some areas indicates wall unevenness or profile deformation. Check horizontal and vertical alignment with a level.

If minor gaps are found at angles, they can be eliminated with final trimming. Mark problematic areas with a pencil and carefully trim with a blade or sand with sandpaper. Sometimes removing a tenth of a millimeter is sufficient to achieve perfect alignment.

Fitting is especially important when working with long moldings. Ensure you have enough material, that all details are cut correctly, and that the overall composition looks harmonious. It is better to spend extra time on fitting than to discover an error after gluing the molding.

Typical Errors and Their Solutions

Incorrect Orientation in the Cut

The most common mistake among beginners is incorrect placement of the molding in the cut. The molding is installed upside down, or the sides adjacent to the wall and ceiling are swapped. Result—cut angles do not fit, large gaps form, which cannot be masked.

Solution: Before each cut, visualize how the molding will be positioned on the wall. Which side will be down, which up, which side will be adjacent to the wall. Make small marks on the molding indicating top, bottom, and direction. Some masters even draw an arrow indicating the cut direction.

If the error has already been made and the molding has been cut incorrectly, do not attempt to use it—the result will still be unsatisfactory. Cut a new piece, carefully checking the orientation. The damaged piece can be used for practice or on less noticeable areas.

To prevent this error, make a test cut on short molding pieces. Cut two samples and try to join them. If the fit is perfect, remember the molding's position in the cut and repeat it for all subsequent cuts. You can even take a photo of the correct position on your smartphone for reference.

Excessive Pressure During Cutting

Many believe that the harder you press on the saw, the faster and better the cut will be. In reality, excessive pressure causes molding deformation, chipping, and bending of the cut line. The material compresses under load, and the saw moves unevenly.

Solution: Let the saw do the work. Sharp teeth easily cut polystyrene with minimal pressure. Your task is only to guide the tool and maintain even movement speed. Pressure should be sufficient only to ensure the teeth contact the material.

If you find yourself pressing hard on the saw, it means the blade is dull. Replace the blade or use another saw. Working with a dull tool not only yields poor results but is also dangerous—the saw may slip under heavy pressure and cause injury.

Practice on scraps. Try cutting with different pressures and find the optimal one. You will notice that light pressure yields cleaner cuts, though it may require slightly more time. Quality matters more than speed—hurrying in finishing work always ends in rework.

Cutting without prior marking

Attempting to cut 'by eye', without clear marking - a sure path to errors. Even experienced masters always mark the cut area. The human eye cannot accurately assess distance, and an error of several millimeters is critical when joining moldings.

Solution: Always carefully measure and mark the cut area. Use a tape measure to determine the distance, mark the cut point with a pencil on both sides of the molding. Connect the points with a straightedge. Double-check measurements before cutting.

When marking, account for the saw blade thickness. The saw cuts a certain width of material (usually 1-2 mm), and this must be considered in measurements. Cut along the outer edge of the marking line, leaving it on the cut piece. The finished part will then have the exact required length.

For complex configurations, use cardboard templates. Cut out the desired shape from cardboard, place it against the molding, and trace the outline. This guarantees accuracy and allows you to verify measurements before cutting expensive material.

Ignoring wall characteristics

Often forgotten: walls are rarely perfectly flat. Irregularities, bumps, and dips can reach several millimeters, and with tight molding fit, these defects become noticeable. The molding either doesn't adhere properly to the wall in some areas or replicates all irregularities, which looks unprofessional.

Solution: Before installation, inspect the walls and identify problematic areas. To check flatness, use a long straightedge or level. Place it against the wall and check for gaps. Minor irregularities (up to 2-3 mm) can be compensated for by the flexibility of the adhesive and the molding itself.

Serious irregularities are better addressed beforemolding installation. Bumps can be sanded down, dips filled with putty. If leveling is impossible, choose moldings with a flat back surface—they adapt better to uneven walls.

When installing on very uneven walls, use a more flexible adhesive that will fill gaps. However, this is a last resort—the adhesive layer should not be too thick. It’s better to spend time preparing the surface than trying to compensate for flaws with adhesive.

Cutting long moldings without support

Attempting to cut a long molding when one end hangs unsupported is a common mistake. Under its own weight, the molding sags, resulting in inaccurate cuts. Additionally, the hanging end may break at the most inconvenient moment.

Solution: Ensure support along the entire length of the molding. Use additional stands, chairs, or ask a helper to hold the free end. The molding must lie flat, without sagging or misalignment. This is especially important when working with thin-profile moldings.

For convenience, you can construct a simple support structure using two sawhorses or chairs of equal height. Place a board on them, which the molding will rest on during cutting. Ensure the entire structure is stable and does not wobble.

When cutting in a sawhorse, it is especially important that the long end of the molding does not create a lever that could tip over the sawhorse. Secure the sawhorse to the workbench with clamps or use a model with non-slip legs. Safety and accuracy must always be prioritized.

Using an inappropriate tool

Attempting to cut polystyrene moldings with a coarse saw with large teeth, a kitchen knife, or other unsuitable tools is doomed to failure. The result: ragged edges, chips, uneven cuts, and damaged material.

Solution: Use only tools intended for this task. If you don’t have the appropriate saw, it’s better to purchase one specifically for this project. A quality tool will last long and be useful for future work. Saving money on tools ultimately costs more due to damaged material.

How to cut polystyrene molding- not a trivial question. The right tool is half the success. Investing in a quality saw, miter gauge, and sharp blades will pay off with perfect results and saved time. Do not improvise with tools.

It is advisable to purchase a professional adjustable miter gauge if you plan to regularly work with decorative elements. Its cost is higher than a standard one, but the ability to precisely set any angle and the convenience of use justify the expense.

Frequently asked questions

Can polystyrene moldings be cut with a jigsaw?

Technically possible, but not recommended. High saw blade speed causes material heating and melting, resulting in melted and uneven edges. If no other option exists, use the lowest speed, a plastic saw blade, and make frequent breaks for cooling. However, manual cutting yields significantly better results.

What to do if the molding cracked during cutting?

A cracked molding cannot be used—the crack will be visible and may grow over time. Causes of cracking: cold material, excessive pressure during cutting, impact, or drop. Before attempting again, ensure the molding is at room temperature, cut carefully without pressure. Work in a warm room.

Do the ends of moldings need to be primed after cutting?

Priming ends is not mandatory, but recommended if you plan to paint the moldings. Ends are more porous than the front surface and absorb paint well. Without primer, multiple paint layers may be needed to achieve uniform color. Use water-based acrylic primer.

How to join moldings if the room angle is not 90 degrees?

Measure the actual angle with a protractor. Divide the obtained value in half—this will be the cutting angle for each molding. For example, if the room angle is 88 degrees, cut the moldings at 44 degrees. For precise cutting, use an adjustable miter gauge or make a cardboard template.

Can the gap in the corner be fixed after installing the molding?

A small gap (up to 2-3 mm) can be masked with acrylic caulk or putty. Apply the material into the gap, smooth it with a wet finger, and let it dry. Then sand lightly with fine-grit sandpaper and paint. Large gaps are better addressed by removing the molding, properly trimming, and reinstalling.

Chipping is caused by a dull tool, incorrect cutting technique, or low-quality material. Ensure you use a sharp saw with fine teeth, cut smoothly without jerking. Quality

has a uniform dense structure and practically does not chip when cut correctly.Today, it is available in an extensive range — from classic moldings with stucco to modern minimalist solutions. The Chelyabinsk market for construction and finishing materials offers a variety of options for any budget and design task.has a uniform dense structure and practically does not crumble when cut properly.

Do you need to sand the molding before painting?

Light sanding with fine-grit sandpaper (P240-P320) improves paint adhesion, especially if the molding surface is smooth and glossy. Sand carefully, removing only the top glossy layer. After sanding, be sure to remove dust with a damp cloth and let it dry before priming and painting.

How to cut molding to create a decorative frame?

For a rectangular frame, all four corners are cut at 45 degrees. Measure the required dimensions, add twice the molding width to each side (to account for beveled corners). Cut the corners carefully, paying attention to the cutting direction — opposite sides must be mirror images. Use a template to check.

Conclusion

Working with decorative interior elements requires attention to detail, patience, and the right approach. Cutting polystyrene molding is a simple process but requires precision and care. Following the recommendations in this guide, you can achieve a professional result even without special experience.

Remember the basic principles: use the right tool, work slowly, carefully mark each cut, and follow safety procedures. Do not neglect preparation and finishing — these stages are just as important as the cutting itself. Qualityprofile preparationand careful work guarantee a flawless result.

STAVROS Company offers a wide range of high-quality polystyrene moldings. STAVROS products are distinguished by uniform structure, precise geometry, and excellent performance characteristics. With STAVROS moldings, your interior will achieve completeness and elegance, and the installation process will become a pleasant and easy task.

Successful repair and perfectly straight corners to you!