How to Operate JHIMS L5 Solder Paste Printer – Step-by-Step Video Guide (2026)

Solder Paste Printer Knowledge Base — Original Engineering Insights

Stencil printing is as much a rheology problem as a mechanics one. Solder paste is thixotropic: under the shear of the squeegee it thins and flows into the stencil apertures, then thickens again the instant it stops, holding its shape on the pad. The variables that decide whether that deposit is flat, crisp and repeatable are paste viscosity (as delivered and as it ages), stencil thickness and aperture design, and squeegee pressure, angle and speed. When these drift you get the classic defects — slumping and bridging, open joints, or a deposit that looks right on the board but does not reflow correctly. The sections below are the working knowledge that goes beyond the operator manual: how to diagnose a fault, the consumables and filters that keep the machine healthy, the maintenance cycle that stops drift before it starts, and a fast parameter reference for a correct setup on the floor.

Fault Diagnosis Table

Start-up & Shift Checklist

• Air pressure gauge within the specified range (4-6 kgf/cm²)
• Platform: ball screw and guide screws tight; work surfaces clean
• Squeegee: belt tension and wear OK; pressure calibrated
• Cleaning unit: paper roller feeds; spray nozzle clear; filter net cleaned
• Vision: board / stencil image sharp; LED brightness OK
• Stencil frame: left-right height parallel; cylinder no air leak
• Conveyor: belt tension OK with no slippage; stop cylinder no leak; rail height consistent
• Electrical: ground continuity; air filter drained; connectors tight
• No alarm indicators on the machine

Maintenance Cycle Table

Parameter Quick-Reference Table

Decision Tree: Print Quality Problem?

The 2D inspection camera scans the deposited paste pattern after printing. By measuring the area of each paste deposit against the stencil aperture area, the system detects insufficient paste (area too small), excess paste (area too large) and bridging (paste connecting adjacent pads). It cannot measure height directly — that requires 3D/SPI — but area-based detection catches most print defects before reflow.

Defects caught at the printer cost seconds to fix (clean stencil, reprint). Defects caught after reflow cost minutes or hours (desoldering, rework, or scrapping). The 2D inspection is the cheapest quality gate in the entire SMT line.

A poorly taught fiducial shifts every print on the board. The error compounds across the board — a 0.1mm mark error at the origin becomes a 0.5mm shift at the far corner for a 300mm board. Teach marks carefully with the crosshair zoomed in.

The L5 supports 0201 components and 0.25mm pitch. For such fine-pitch boards, use diagonal marks, lower pressure, slower speed and three-stage separation to keep registration and release consistent.

Six Most Common Operator Mistakes

1. Powering on without removing the transport lock block can damage the print head and drives.
2. Skipping the pre-startup air pressure check causes false alarms and unstable printing.
3. Teaching only one fiducial cannot correct board rotation — use two marks for reliable registration.
4. Fine-pitch boards need lower squeegee pressure and slower speed; defaults smear fine apertures.
5. Repeated 2D alarms indicate a real process drift. Investigate the cause instead of disabling the alarm.
6. Mixed or expired solder paste contaminates apertures and causes skip-print defects.

These six mistakes share one characteristic: each of them looks like a shortcut and costs more time than it saves. Removing the transport lock block is the clearest example — it takes seconds and skipping it risks damaging the print head and drives, which is a service event rather than a delay. The pre-startup air pressure check matters for a similar reason: printing and stencil cleaning both run on air, so a supply below the 4–6 kgf/cm² band produces false alarms and unstable deposits that operators then try to correct with parameter changes, moving a clean machine away from a known-good recipe. Teaching a single fiducial cannot correct board rotation, so registration errors appear as intermittent misalignment that is very hard to diagnose later; two marks solve it at the start.

The remaining three are process discipline. Fine-pitch boards need lower squeegee pressure and slower speed than the defaults, because default settings smear fine apertures even though they work on coarse boards. Repeated 2D inspection alarms should be read as a real process drift rather than an alarm to silence; disabling the check removes the cheapest quality gate on the line. And mixed or expired solder paste contaminates apertures and produces skip-print defects that look like a printer fault but are a material fault, so paste identity and expiry are part of the printing process rather than a stores issue.

Seven Field Rules from 15 Years of Installations

1. Always back up system data before relocating the machine or changing hardware.
2. Check the air pressure (4–6 kgf/cm²) before every shift — it drives both printing and cleaning.
3. Match squeegee type (rubber or steel, 45°/55°/60°) to the paste and aperture geometry.
4. Use three-stage separation for fine-pitch boards to avoid paste strings.
5. Clean the CCD lens weekly — vision quality drives both alignment and inspection.
6. Verify first-board print quality every shift; a 30-second check catches drift early.
7. Document threshold settings with each recipe. When quality drifts, you know what changed.

What makes these seven rules worth following is that each one is a habit rather than a task. Backing up system data before relocating a machine or changing hardware costs minutes and decides whether a recovery is a restore or a re-teach. Checking air pressure before every shift takes seconds and removes the most common cause of unstable printing. Matching squeegee type — rubber or steel, in 45°, 55° or 60° profiles — to the paste and aperture geometry is a decision that should be made once per product and then recorded, not re-invented per shift. Three-stage separation for fine-pitch boards is the difference between clean release and paste strings that bridge the next print.

The last three rules are about visibility. Cleaning the CCD lens weekly keeps vision quality predictable, and vision drives both alignment and 2D inspection, so a dirty lens degrades two functions at once. Verifying the first board every shift takes about 30 seconds and catches drift before a batch is produced rather than after it is inspected. Documenting threshold settings with each recipe means that when quality does drift, the operator can compare against a recorded baseline instead of guessing what changed — which is the single most useful piece of documentation a printing process can have.