SOP for the HoliPress 38 manual plastic injection molding machine

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1. Purpose

To safely and efficiently operate the HoliPress 38 for manual plastic injection molding to produce high-quality plastic parts, prototypes, or small batch productions.

2. Scope

Applicable to all operators using the HoliPress 38 for prototyping, material testing, recycling, and small-scale production in workshops, labs, or educational settings.

3. Safety Precautions

  • Always wear provided personal protective equipment (PPE): safety glasses and thermal gloves.
  • Ensure the machine is placed on a stable, flat surface.
  • Keep hands and loose clothing away from moving parts during operation.
  • Allow the machine to cool down before maintenance or cleaning.

4. Machine Description

  • Injection volume capacity: 38 \({\rm cm^3}\).
  • Triple heating zones for precise temperature control up to 320 °C.
  • Length-adjustable injection lever for ergonomic operation.
  • Adjustable mold height up to 190 mm.
  • PID temperature control for consistent melting.
  • Manual clamping vice compatible with various mold types (metal, SLA, FDM).
  • Injection speed adjustable between 2 to 10 seconds.
  • Power consumption: 860 W at 220 V.

5. Preparation

  • Inspect the machine and all accessories for damage or wear.
  • Select and install the appropriate mold in the clamping vice; secure firmly.
  • Adjust the mold height as needed for your specific mold.
  • Install the shut-off nozzle (5 mm heated nozzle included).
  • Preheat the machine using the triple heating zones:
    • Set each temperature zone according to the plastic material specifications (consult material datasheets).
    • Allow the machine to reach stable set temperatures before injection.

6. Material Loading

  • Use industrial-grade plastic granules suitable for injection at ≤320°C.
  • Load the plastic granules into the heating chamber.
  • Rotate the lever system to feed and melt the plastic.
  • Ensure the plastic is properly melted and plasticized before injecting.

7. Injection Process

  • Adjust the injection lever length for comfortable operation.
  • Begin the injection by pressing the lever steadily to inject melted plastic into the mold cavity.
  • Maintain closing pressure using the manual clamping vice during injection.
  • Allow the plastic to cool and solidify in the mold.
  • Release the mold clamp and remove the molded part carefully.

8. Post-Injection

  • Purge the machine using the included purge block to clean out residual plastic.
  • Clean the nozzle and heating chamber with supplied cleaning tools.
  • Store unused granules properly to avoid contamination.
  • Inspect the injected parts for quality and defects.
  • Never swich off the machine with the piston in the injection position; always place the piston back in locked position before powering down.

9. Maintenance

  • Regularly clean the nozzle and purge block after use to prevent clogging.
  • Check the heating elements and temperature sensors periodically.
  • Lubricate moving parts as recommended by the manufacturer.
  • Report any malfunction or unusual operation immediately.

10. Troubleshooting

  • Inconsistent injection pressure or plastic flow may indicate blockage—clean nozzle and purge system.
  • Temperature instability—check PID controller settings and heating zones.
  • Mold leakage—ensure mold is properly clamped and seals are intact.

11. Additional Notes

  • HoliPress 38 supports a wide range of plastics including recycled granules and technical materials.
  • Use the machine as a flexible tool for prototypes, education, material characterization, and small batch production.
  • Consult specific plastic material datasheets for melting temperatures and injection parameters.