Special Printing Techniques

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This extra explains special techniques that modify printing behavior. Each technique attaches to a specific settings object.

Print‑level techniques (Settings)

Use these at the job level by passing them to Settings(..., special_print_techniques=[...]).

from pymfcad import Settings, PrintUnderVacuum

vacuum = PrintUnderVacuum(
    enabled=True,
    target_vacuum_level_torr=10.0,
    vacuum_wait_time=30.0,
)

settings = Settings(
    printer=printer,
    resin=resin,
    default_position_settings=PositionSettings(),
    default_exposure_settings=ExposureSettings(),
    special_print_techniques=[vacuum],
)

This adds a Print under vacuum block to the JSON print settings.

What it does: Pulls a vacuum in the print chamber and runs the print under vacuum.

Layer‑level techniques (PositionSettings)

These modify motion per layer and are attached to PositionSettings.

Squeeze out resin

What it does: Drives the build platform to a target force beyond the programmed layer thickness. This helps resolve layer thickness issues, especially in large print areas and very small layer thicknesses (sub 5 um) or with viscous resins.

from pymfcad import PositionSettings, SqueezeOutResin

pos = PositionSettings(
    distance_up=1.0,
    final_wait=0.0,
    special_layer_techniques=[
        SqueezeOutResin(enabled=True, count=2, squeeze_force=5.0, squeeze_time=200.0)
    ],
)

Image‑level techniques (ExposureSettings)

These modify exposure behavior per layer and are attached to ExposureSettings.

Zero‑micron layers

Repeats an exposure in a subsequent layer with a 0 um Z move between layers. This helps flush out partially polymerized material.

from pymfcad import ExposureSettings, ZeroMicronLayer

exp = ExposureSettings(
    bulk_exposure_multiplier=0.25,
    special_image_techniques=[ZeroMicronLayer(enabled=True, count=2)],
)

Raises the build platform and exposes on film (not connected to bulk material/build platform). This allows flushing partially polymerized material beyond the layer in Z and enables very small Z voids or layers that are not attached to each other.

from pymfcad import ExposureSettings, PrintOnFilm

exp = ExposureSettings(
    bulk_exposure_multiplier=1.0,
    special_image_techniques=[PrintOnFilm(enabled=True, distance_up_mm=0.3)],
)

Notes

  • Techniques are optional and can be mixed.
  • If a technique is disabled (enabled=False), it’s preserved but ignored.
  • These settings are serialized into the JSON print file under Special print techniques or Special layer techniques.