Calibration & Motion MODULE

Minimum Layer Time & Cooling Speed Calculator

Prevent melting, drooping, and heat radiation damage on small print features. Calculates required slicer speed slowdown, fan speeds, and prime tower needs.

Filament Polymer

Each polymer has distinct crystallization rates and heat capacities.

Single Layer Print Time4.0s

seconds

Inspect layer duration in slicer preview color-coded by "Layer Time".

Nominal Print Speed (mm/s)

mm/s

Your standard outer wall / perimeters printing speed.

WARNING: COOLING DEFICITPLA (Polylactic Acid)

Layer prints in 4.0s (below 8.0s target). Slicer should throttle print speed to allow cooling without heat radiation damage.

Recommended Throttled Speed

60 mm/s

Target Min Time

8.0s

Nozzle Heat-Soak Hazard: Sacrificial Prime Tower Strongly Advised

On extremely small features (under 3-4 seconds), slowing down the nozzle to extreme crawls keeps a 200°C+ hot aluminum block hovering directly above molten plastic, radiant-melting the layer below. The ideal remedy is to print a sacrificial prime tower or print two parts simultaneously 50mm apart to let the layer cool while the head travels.

Slicer Cooling Configuration (OrcaSlicer / Bambu Studio / PrusaSlicer)Filament Settings > Cooling

Copy Slicer Cooling Config

# Slicer Cooling Configuration

01 / PROTOCOL

Measurement & Operating Instructions

STEP 01

1. Select Filament Polymer

Choose your plastic (PLA needs high fan; ABS/ASA requires minimal fan and enclosed ambient heat).

STEP 02

2. Input Layer Duration from Slicer

Check your slicer preview color-coded by "Layer Time" on small tips, horns, or miniature swords.

STEP 03

3. Configure Slicer Cooling Tab

Apply the calculated slowdown threshold and minimum safe speed in OrcaSlicer or Bambu Studio.

02 / MATHEMATICS

Thermal Dissipation & Slicer Cooling Thresholds

Calculates whether molten filament has adequate time to freeze below its glass transition temperature before the subsequent layer is deposited.

Throttled Speed = Base Speed × (Current Layer Time / Target Min Layer Time) | Critical Dwell Threshold < 3.0s

Real-World Worked Benchmark:

Printing a 4.0s spire in PLA (target 8.0s min cooling) at 120 mm/s: The slicer must throttle travel and extrusion speed to 60 mm/s. Layers under 3.0s require a sacrificial prime tower to prevent radiant nozzle melting.

Frequently Asked Questions

Why do small tips and spires curl up or melt into blobs?

When printing a tiny cross-section, the nozzle returns to the same spot before the previous plastic has cooled below glass transition temperature. The persistent radiant heat from the hot block liquefies the underlying plastic.

How does Minimum Layer Time in Bambu Studio, OrcaSlicer, or Cura prevent melting?

Slicers allow you to define a Minimum Layer Time (typically 6 to 10 seconds for PLA). If a layer takes less time, the slicer automatically throttles print speed to give the layer cooling fan time to solidify the plastic.

How does a sacrificial prime tower fix cooling issues?

By forcing the toolhead to travel away from the delicate miniature and spend 10-15 seconds printing a hollow cylinder elsewhere on the bed, the miniature has time to naturally solidify in ambient air.

What is the optimal minimum layer time for PETG and ABS?

PETG needs moderate cooling and benefits from a 10 to 12 second minimum layer time. ABS and ASA cool faster in a heated chamber, but still require 8 to 10 seconds on fine pinnacles to prevent droop.

Can 100% part cooling fan cause weak layer adhesion on PLA?

Yes. While 100% cooling fan creates pristine overhangs and bridges, excessive cooling on wide structural infill areas can cool the polymer interface too rapidly, reducing inter-layer molecular diffusion and lowering Z-axis tensile strength.

CALCULATOR SUITE