TT - Sanding Guide: From Substrate to Finished Surface
Craftsman Guide / Sanding Technique Sanding Guide: From Substrate to Finished Surface. Instructions for machinery, abrasives, and sanding techniques divided across the four work phases.. Jump directl…
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by tomas martinsson
Craftsman Guide / Sanding Technique
Sanding Guide: From Substrate to Finished Surface
Instructions for machinery, abrasives, and sanding techniques divided across the four work phases.
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💡 Sanding Determines the Final Result: Sanding is one of the single most crucial steps in the entire process. Proper technique ensures optimal adhesion and lays the foundation for how flat, uniform, and refined the finished surface will appear.
🧹 Critical Cleaning Routine Throughout the Process:
After completing each sanding stage (regardless of which layer has been sanded), you must vacuum the surface thoroughly and wipe it down with a completely dry microfiber cloth.
• Residual abrasive grit from the base coat will score deep scratches into subsequent finish coats during troweling.
• Sanding dust from Microdeck and Microfino absorbs liquid and causes subsequent coats to flash-dry prematurely during application.
• Prior to sealing and topcoating, all dust must be completely removed. Trapped dust particles become encapsulated by the sealer, producing permanent dark specks—be exceptionally thorough around corners and perimeter junctions.
• Sanding dust from Microdeck and Microfino absorbs liquid and causes subsequent coats to flash-dry prematurely during application.
• Prior to sealing and topcoating, all dust must be completely removed. Trapped dust particles become encapsulated by the sealer, producing permanent dark specks—be exceptionally thorough around corners and perimeter junctions.
1. Substrates (Tiles, Pavers & Self-Leveling Screed)
• Tiles & Pavers: Grind the tiles with a diamond concrete grinder connected to a dust extractor before starting. This roughens the smooth glaze for maximum adhesion and flattens any lipped or protruding tile edges.
• Self-Leveling Screed: Before applying primer to self-leveling screed, always abrade the surface with 40 grit. This removes the surface laitance formed during drying and opens the pores to allow deep primer penetration.
2. Base Coat (Microbase / Natture L)
The base coat contains coarser aggregates to build mechanical strength. Remember that the flatness and level of finish achieved after the second base coat will dictate the final surface texture.
• Abrasives: Use 40-grit sandpaper or a 50-grit Diamond Pad on a random orbital sander.
• Important for Diamond Pads: Always operate at low RPM and with very light pressure on the machine; excessive speed and force will glaze and burn out the pads prematurely.
• Corners and Angles: Sand internal and external corners crisp and straight by hand using folded sandpaper. On the first base coat, a multi-tool equipped with a diamond blade may be used to clean up internal corners—note that this is only permitted on the first base coat.
Tip: Trowel the corners neatly during application to minimize the need for corrective sanding afterward.
• Important for Diamond Pads: Always operate at low RPM and with very light pressure on the machine; excessive speed and force will glaze and burn out the pads prematurely.
• Corners and Angles: Sand internal and external corners crisp and straight by hand using folded sandpaper. On the first base coat, a multi-tool equipped with a diamond blade may be used to clean up internal corners—note that this is only permitted on the first base coat.
Tip: Trowel the corners neatly during application to minimize the need for corrective sanding afterward.
3. Finish Coats (Microdeck & Microfino)
Work with great care when sanding the decorative finish coats. Any significant level corrections belong in the substrate or base coat—finish coats build an extremely thin film. Do not sand aggressively, as this risks cutting through to the base coat underneath and producing dark burnish marks.
• Microdeck / Natture M: Sand with 80 grit on a random orbital sander. For detailing and corners, sand with 120 grit by hand.
• Microfino: Sand gently with 120 grit on a random orbital sander. For hand-sanding in angles and corners, use 180–240 grit.
4. Intermediate Sanding (Prior to Topcoat)
• Intermediate Sanding: Lightly abrade the sealed surface with 400-grit sandpaper by hand (or at low speed with a random orbital sander under zero downward pressure) to knock down raised fibers and ensure full intercoat adhesion.
⚠️ NOTE: This is done directly before applying the topcoat polyurethane (Topsealer), NOT before the pre-sealer (TT Presealer).
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TT - Substrate Preparation on Tiles
