Print profiles

Summary¶

Every libdrone part has its own print profile tuned to its material, function, and orientation. Arm shafts are printed vertically at 0.15 mm layers with 8 perimeters because inter-layer strength and fine surface detail matter. X body PCCF layers are printed flat at 0.20 mm with 40% infill because area coverage and dimensional stability matter more than fine detail. Using the wrong profile for a part wastes filament or produces a structurally inadequate result.

Concept¶

Why parts need different profiles¶

Print profiles are not just about quality — they are about function. The key variables are:

Layer height — thinner layers give more surface detail and better layer adhesion on overhangs but increase print time. Structural parts that are loaded in the Z axis (perpendicular to layers) need thinner layers. Flat structural parts need fewer, heavier layers.

Perimeters — more perimeters mean more material at the part boundary, which directly increases wall strength and impact resistance. Crash-sacrificial parts (arm shafts) need many perimeters. Structural flat parts (X body layers) need fewer because their strength is governed by layer count and infill.

Infill — determines internal density. Higher infill increases mass and compressive strength. Most parts use grid infill for predictable load paths. Gyroid infill is an alternative for parts that need good multi-directional strength with lower mass.

Orientation — the most critical setting. Layer lines must be oriented so the strongest axis (along-layer) aligns with the primary load direction. A vertically printed arm shaft has layers perpendicular to the bending load — maximum strength. A horizontally printed arm shaft has layers parallel to the bending load — minimal delamination resistance.

Reference¶

Hardware requirements¶

Item	Specification
Nozzle	0.6 mm hardened steel — mandatory for all parts
Spare nozzle	Keep one in reserve — PCCF and PETG-CF are abrasive
Print sheet	Satin or textured PEI
Glue stick	Mandatory for PCCF; not required for PETG, PETG-CF, or ASA

Arm shaft — PETG (primary crash element)¶

Setting	Value
Layer height	0.15 mm
Perimeters	8
Infill	30% Grid
Solid layers top/bottom	6 / 6
Brim	5 mm
Orientation	VERTICAL — mandatory
Nozzle temp	255°C
Bed temp	85°C
Cooling	30–40%
Extrusion multiplier	0.96–0.98

Critical notes: disable "Thick Bridges" for counterbore surfaces. Verify MR30 wire channel is not filled with support material. Drop test from 1 m: pass = flex/mark, fail = crack/delamination.

Arm tab — PETG¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	30% Grid
Orientation	Horizontal (flat)
Nozzle temp	255°C
Bed temp	85°C

Arm cover passive — PETG-CF¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	30% Grid
Orientation	Flat
Nozzle temp	270–280°C
Bed temp	85°C
Respirator	FFP3 mandatory — carbon fibre particles

Arm cover active — PETG¶

Same settings as arm tab. Orientation: flat.

X body PCCF layers (×3 identical)¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	40% Grid or Gyroid
Solid layers top/bottom	5 / 5
Orientation	Flat
Nozzle temp	290–300°C
Bed temp	110°C
Enclosure	Required — door closed >40°C
Cooling	0%
Glue stick	Mandatory on PEI

X body PETG top layer¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	30% Grid
Orientation	Flat, face-up
Nozzle temp	255°C
Bed temp	85°C
Supports	Required inside GX12 chimney bores

After print: install 2 × M3 heat-set inserts in mast boss pads at 200–210°C. Do this before epoxy wipe — epoxy in threads ruins them.

Platform — PETG¶

Setting	Value
Layer height	0.20 mm
Perimeters	4 minimum
Infill	30% Grid
Orientation	Flat, face-up
Nozzle temp	255°C
Bed temp	85°C
Supports	Required inside both GX12 chimney bores
Print time	~3.5 hours

After print: remove chimney bore supports with a pick — do NOT ream with a round drill (destroys anti-rotation flats). Verify Coupon 10 criteria against full Platform before proceeding.

Backplane — PETG Natural¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	65% open area (lattice — designed in geometry, not slicer infill)
Orientation	Flat, face-up
Supports	None
Print time	~1 hour

GPS/camera bracket — PETG Natural¶

Flat, standard PETG settings. Print coupon 9 first.

ASA bumpers (×4 + spares)¶

Setting	Value
Layer height	0.20 mm
Perimeters	4
Infill	30% Grid
Orientation	Flat
Nozzle temp	255°C
Bed temp	95°C
Enclosure	Strongly recommended
Cooling	10–20%

Mass targets by part¶

Part	Target mass
Arm shaft (×4)	15.0 g each / 60.0 g total
Arm tab (×8)	—
X body PETG bottom (×1)	7.0 g
X body PCCF layers (×3)	9.0 g each / 27.0 g total
X body PETG top (×1)	18.0 g
Platform (×1)	60.0 g
Backplane (×1)	7.0 g
Full printed structure + rods + isolation + bolts	265.0 g

Procedure¶

Extrusion multiplier calibration¶

Before any production print: 1. Print Coupon 1 (four test bores: 2.05, 2.10, 2.15, 2.20 mm). 2. Measure each bore with calipers. 3. Adjust extrusion multiplier until the 2.20 mm bore measures 2.20 ± 0.05 mm. 4. Record the multiplier (typically 0.96–0.98 for PETG). 5. Apply this multiplier to all PETG profiles before production.

Rationale¶

Why 8 perimeters on arm shafts¶

The arm shaft is a sacrificial fuse — it must absorb crash energy by deforming, not by fracturing at the first layer boundary. Eight perimeters creates a solid, continuous wall of PETG with no weak inter-perimeter bonds that would cause premature delamination. The shaft deforms plastically rather than splitting.

Why 0% cooling on PCCF¶

Polycarbonate inter-layer adhesion depends on the top layer of material staying above glass transition temperature long enough for the new layer to fuse with it. Cooling fans quench the surface before fusion is complete, creating weak layer boundaries that fail under structural load. PCCF with 0% cooling produces significantly stronger parts despite the slight reduction in overhangs quality — and the X body layers have no complex overhangs.

Connections¶

requires: - petg - pccf - asa - freecad-document-setup related: - coupon-validation - production-run-order - stl-export-and-slicer-setup leads_to: - coupon-validation - production-run-order