Hydro-clean LRS — Stencil & Screen Cleaning

The Problem This Machine Solves

Every stencil print cycle leaves residue in the apertures — microscopic solder paste particles that accumulate with each board printed. After 50–100 prints, aperture clogging degrades paste release, causing insufficient solder deposits on fine-pitch pads. The fix is simple: clean the stencil. But doing it right requires removing paste from apertures as narrow as 0.15mm (0.006 in) without damaging the stencil foil, and doing it fast enough not to bottleneck the print cycle.

What the LRS Handles

The Hydro-clean LRS is a batch cleaning machine designed specifically for stencils, screens, and small-batch PCBA cleaning. It supports stencils up to 29 × 32 in (737 × 813 mm) — the standard range for most SMT production environments. Beyond stencils, it cleans printing screens used in thick-film and paste printing, and handles small-batch PCBA cleaning for prototypes and low-volume production runs.

Key Specifications

Target Workpieces	Stencils, screens, small-batch PCBA
Maximum Stencil Size	29 × 32 in (737 × 813 mm)
Cleaning Technology	Spray-based — chemistry delivery across stencil surface
Process Cycle	Chemistry spray → DI water rinse → Drying
Aperture Cleaning	Removes paste buildup for consistent print quality
Screen Cleaning	Supports thick-film and paste printing screens
PCBA Cleaning	Small-batch — prototypes, low-volume production

Control System: Windows OS with touchscreen HMI — programmable recipe storage/recall, cycle data logging, password-protected process parameters, and exportable production records for traceability (IPC-6012, MIL-STD-883, AS9100).

Applications

• Stencil cleaning between print cycles — removing paste residue from apertures to maintain print quality
• End-of-shift stencil cleaning — thorough cleaning before storage to prevent paste hardening
• Screen cleaning — thick-film printing screens, paste printing screens, and membrane printing frames
• Misprint board cleaning — recovering boards with incorrect paste deposits
• Small-batch PCBA cleaning — prototype runs, engineering builds, low-volume production
• Stencil life extension — regular cleaning prevents aperture erosion from hardened paste

How It Works

The operator places the stencil, screen, or PCBA into the cleaning chamber. The cycle begins with heated cleaning chemistry sprayed across the workpiece surface — dissolving solder paste, flux residue, and organic contamination. Chemistry penetrates into stencil apertures, loosening paste particles from aperture walls. DI water rinse removes chemistry and dissolved contamination. The drying step evaporates all moisture, leaving the stencil clean and dry — ready for immediate reuse.

For stencils, the spray pattern is optimized for aperture penetration — chemistry flows through the apertures, not just across the surface. This is critical for fine-pitch stencils where aperture walls are 0.10–0.15mm (0.004–0.006 in) wide and paste residue builds up on the interior surfaces.

Hydro-clean LRS vs. Alternatives

Feature	Hydro-clean LRS	Manual Wipe	Ultrasonic Stencil Cleaner
Aperture penetration	Spray — flows through apertures	Surface only — can’t reach inside	Yes — but risk of foil damage
Stencil foil safety	Non-contact spray — no mechanical stress	Wiper contact — can dent or tear	Cavitation can erode foil edges
Cycle time	5–10 minutes fully automated	5–15 minutes manual	10–20 minutes
Repeatability	Identical cycle every time	Operator dependent	Consistent
Screen compatibility	Yes — thick-film and paste screens	Impractical for large screens	Yes
Small-batch PCBA	Yes — integrated capability	Manual solvent clean	Separate equipment needed

What to Send for a Quote

1. Stencil dimensions — maximum length × width × foil thickness
2. Aperture sizes — minimum aperture width on fine-pitch stencils
3. Solder paste type — leaded, lead-free, water-soluble, no-clean
4. Print volume — boards per stencil before cleaning is needed
5. Screen types — if also cleaning thick-film or paste printing screens
6. PCBA cleaning needs — board dimensions and volume if also cleaning boards

Target Industries

SMT contract manufacturers, electronics assembly lines, prototype shops, LED assembly, thick-film hybrid manufacturers, any facility running stencil-based paste printing.

Related Equipment

• Hydro-clean MAX — oversized stencil cleaning for stencils exceeding standard dimensions (up to 1500 × 700 mm)
• Hydro-clean AS — automatic PCBA cleaning with linear direct spray for populated boards
• Hydro-clean LDS — low stand-off PCBA cleaning for BGA, QFN, and CSP packages