Antminer S21+ (Plus) Thermal Grease Steel Mesh Stencil

Antminer S21+ (Plus) Thermal Grease Steel Mesh Stencil – Laser-Cut 3-Layer Hashboard Silicone Application Tool

This thermal grease steel mesh stencil is engineered for the Antminer S21+ (Plus) air-cooled hashboard. It features a three-layer design — Left, Right and BOT — perfectly matched to the S21+ hashboard ASIC chip array through a precision laser-cutting process. The mesh lets a technician control both the position and the thickness of the silicone thermal grease layer, so every ASIC chip receives an even, repeatable deposit that improves chip-to-heatsink heat conduction and lifts steady-state hash-rate stability. Available as Left + Right stencils, BOT stencil alone, or the Full Kit (all three layers).

Three-Layer Design — Left, Right & BOT

The S21+ hashboard ASIC array doesn't sit as a single flat zone — it splits across distinct regions, and a single one-size mesh almost never aligns cleanly across all of them. This stencil set addresses that geometry directly with three matched layers: the Left and Right stencils handle the side chip arrays, and the BOT stencil handles the bottom chip array. Each layer is laser-cut to its own footprint, so the apertures sit exactly over the chips they are meant to cover. The Full Kit gives complete hashboard coverage; the Left + Right or BOT options let a repair shop replace only the section it actually uses on a given workflow.

Why Steel Mesh Beats Manual Application

Manual thermal grease application is the single biggest source of post-repair temperature variance on a S21+ hashboard: thick on one chip, thin on the next, smears bridging onto neighbouring components. Using a steel mesh enforces a uniform deposit across the full chip array in a single pull — more uniform, faster, and with significantly higher coverage of the chip top surface than freehand greasing. The downstream effect is straightforward: better thermal interface → better heat dissipation → lower ASIC temperatures → fewer thermal-throttling events and a hash rate that holds at spec instead of decaying.

Laser-Cut Precision for S21+ Hashboard ASIC Layout

The apertures are produced by precision laser cutting, not stamping — laser-cut edges release silicone cleanly without the residual smear stamped meshes leave behind, and the hole geometry stays inside tight tolerance to the S21+ chip footprint. The result on a refurbished hashboard: controlled grease thickness, uniform coverage of the chip top, and no over-application onto the surrounding board, which keeps voltage rails and signal lines clean.

Choose Your Configuration

Left + Right Stencil — for refurbishment work that only touches the two side chip arrays (most common partial-rebuild scenario). BOT Stencil — when the bottom array is the only section being re-greased. Full Kit (Left + Right + BOT) — for a complete hashboard rebuild, new-miner commissioning, or any repair shop building out a permanent S21+ bench setup. Spare layers are easy to add later if a single stencil sees heavy wear before the others.

Application Workflow

Power off the miner and let the hashboard cool before disassembly. Strip the existing thermal compound from the chip tops and the heatsink contact surface with isopropanol and a lint-free wipe. Position the relevant stencil (Left, Right or BOT) over the matching chip array, dispense silicone thermal grease across the surface, and pull cleanly with a flat scraper or squeegee. Lift the stencil straight up — do not slide — to leave even gel deposits on every chip. Repeat for each layer of the array if you are running the Full Kit. Lower the heatsink straight down onto the chips and clamp at the recommended torque before re-energising the miner.

Important Notes — Compatibility, Storage & TIM Choice

This stencil set is compatible only with the Antminer S21+ (Plus) air-cooled hashboard. It is not compatible with the S21+ Hydro, the S21 Pro, the S21 XP, the S21 Hydro or any other S-series variant — the chip-and-heatsink footprint differs and aperture misalignment would destroy the benefit of the laser-cut precision. For best results, pair the stencil with a high-conductivity silicone thermal grease (≥6 W/m·K is the standard recommendation for dense ASIC hashboards); an 8 W/mK silicone gel is the recommended class for this hashboard density. The stencil is a precision tool: handle without bending, store flat in a dry, dust-free environment, and clean residual grease off after every session to keep aperture geometry sharp.

Antminer S21+ Thermal Grease Steel Mesh Specifications

Related Antminer S21+ Parts & Thermal Tools

• BM1370BC ASIC Chip – Antminer S21+ / S21 Pro / S21 XP
• Martech 14cm 7000 RPM Cooling Fan – S21 Pro / S21+
• DOWSIL TC-3080 8W/mK Blue Thermal Gel 1kg – Recommended TIM
• Antminer S21+ Hyd Thermal Grease Stencil – Hydro Sister Tool

Refurbishing a fleet of S21+ miners or kitting out a repair bench? Contact us at contact@lys-sz.com for kit pricing and bulk thermal-grease orders. Worldwide shipping from our Shenzhen warehouse.