Slide 001: Model Preparation and Orientation for Resin Printing

Slide Visual

Slide Overview

This slide covers the critical decisions made before a resin print begins: model orientation, hollowing, drainage, and support strategy. These pre-print decisions have a larger impact on print success and quality than any individual slicer parameter, making this the most important skill in resin print preparation.

Instruction Notes

Orientation Principles for Resin Printing

Unlike FDM, where orientation primarily affects strength and support placement, resin print orientation directly affects whether the print succeeds or fails. The key factor is peel force — the suction force that must be overcome to separate each cured layer from the FEP film.

Peel force is proportional to cross-sectional area. A layer with 50mm × 50mm cross-section (2,500mm²) requires 5x more peel force than a 50mm × 10mm cross-section (500mm²). Excessive peel force can: - Tear the part off the build platform - Delaminate layers - Distort fine features - Damage or puncture the FEP film

Orientation strategies: - Tilt 15-45°: Reduces maximum cross-section per layer across the entire print - Critical surfaces up: Position the most important surfaces facing away from the build plate (upward) to avoid support marks - Symmetrical peel: Orient so the peel "front" advances evenly, not in a sudden large area - Islands avoidance: Avoid orientations that create isolated islands (disconnected cross-sections) in early layers — these have no support and will fail

Hollowing Parts

For parts thicker than 3-4mm, hollowing reduces resin consumption by 40-70% and reduces peel forces significantly. Typical settings: - Wall thickness: 1.5-3.0mm (thinner = more resin savings, thicker = more structural) - Infill: Resin slicers rarely use infill — hollow with adequate wall thickness is standard - Drainage holes: MANDATORY for hollow parts — minimum 1.5mm diameter, ideally 3-5mm - Hole placement: At the lowest point of the print (so resin drains by gravity) and at a second high point (vent hole for air)

Support Types in Resin Printing

Support Type	Tip Diameter	Density	Best For
Light	0.2-0.3mm	Low-Medium	Detailed miniatures, surfaces that matter
Medium	0.4-0.6mm	Medium	General purpose, most prints
Heavy	0.7-1.0mm	High	Large parts, high peel force areas

Supports contact the model at their tips. Larger tips = stronger support but bigger marks to clean. Place heavy supports on non-visible surfaces and light supports near detail features.

Key Talking Points

1. Orientation is the single most impactful decision in resin printing — a perfectly tuned exposure means nothing if peel forces tear the print off the platform
2. Always hollow parts thicker than 3-4mm — it saves resin, reduces peel forces, and prevents trapped uncured resin
3. Every hollow model MUST have drainage holes — trapped liquid resin is both a safety hazard and a print quality problem

Learning Objectives (Concept Check)

• [ ] Students can explain why orientation affects print success in resin printing
• [ ] Students can apply hollowing and drainage hole best practices
• [ ] Students can select appropriate support types for different features of a model

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Last Updated: 2026-03-19