Cement fiber sanding board How should the gaps be handled? How should they be cut?

　　Cement-fiber sanding boards are widely used for interior walls, exterior walls, and partitions, typically supported by light steel framing. Because the board surface is smooth and flat, careful attention to detail is essential during installation to fully showcase the boards' aesthetic appeal. Cement fiber sanding board During use, do you know how to deal with cracks?

　　Method for handling gaps in cement fiber sanding boards:

　　1. Construction ambient temperature: Required range is 5–40°C.

　　2. Preparation: After slightly moistening the joints, clean them with a brush. Only proceed with grouting once the joints are free of visible dust. For example, diluted white latex can be used to clean the joints more effectively. If the wall is a bathroom partition wall, apply a waterproofing primer or a water-repellent agent to the surface of the panel.

　　3. According to the instructions for the joint sealant, prepare the joint filler using a clean container and mixing tool. First add water, then add the filler material, and thoroughly mix the joint filler until it is uniform and free of any dry powder particles. If you are using a pre-mixed filler supplied by the manufacturer, add water or a diluent as directed on the label. The dosage is calculated based on the assumption that the mixture will be used within 40 minutes.

　　4. Use joint filler to seal the joints between slabs on both sides of the slab edges at the same height. The slab joints should be filled thoroughly and densely. After drying, inspect the filled joints for cracks. If cracks are found, analyze the cause and reseal the joints accordingly.

　　5. Different joint-filling methods should be used for boards of different thicknesses. For boards with a thickness of less than 6 mm, the joint filling can be completed in one step; however, for boards thicker than 6 mm, the process should be carried out in two steps. During the first joint-filling step, the joint-filling compound should be embedded into the gap and firmly compacted, and any excess compound at the edges of the gap must be completely removed. The second filling should be performed 24 hours later, using the same method as the first step.

　　6. Joint Treatment: After the joint sealant has dried (approximately 18 hours later), proceed with joint treatment. Apply joint compound to the joint area (about 1 mm thick), then carefully paste paper tape, aligning the fold line of the tape precisely with the board joint and using a spatula to firmly press it down. Ensure there are no air bubbles between the paper tape and the joint compound. Immediately cover the taped area—with a width of 100–120 mm—using another layer of joint compound, making sure the surface of the joint and both side panels is clean and smooth.

　　7. After the first-layer joint filler has dried completely, apply a second layer of joint filler that is 50–60 mm wider on each side than the first layer. The width of the secondary joint treatment should be 200–220 mm (when dealing with right-angle joints, the width of the secondary joint treatment should be 300 mm).

　　8. After the second coat has dried, apply three coats of joint compound, each 50–60 mm wider than the edges of the second coat. The seam width should be 300–360 mm (if the seam is a right-angle joint, the three-coat seam treatment width should be 600 mm).

　　Cutting cement fiber sanding boards typically requires a chainsaw or a mechanical cutting machine. There are three cutting methods:

　　1. The panels can be cut and broken using a heavy-duty cutting machine.

　　2. Typically use a fiber cutting machine.

　　3. Thick boards or high-density boards need to be cut using a power saw.

　　When cutting, pay attention to the wind direction to avoid inhaling dust. Wear a mask or protective gear.