Fast Instructions for Use (IFU) & Printing Parameters for DLP & LCD printers

These Fast Instructions for Use (IFU) provide a rapid starting workflow for using 3Dresyns® photopolymer resin systems with DLP, LCD and MSLA printers. They are intended for fast implementation, early calibration and practical troubleshooting. For deeper optimisation, structured CRT interpretation and broader engineering guidance, use the Instructions for Use (IFU) & Printing Parameters for DLP & LCD printers.

This Fast IFU does not define universal or fully validated processing conditions. It provides a rapid and practical route to identify a suitable starting workflow that must still be validated for the specific resin, printer and application.

1) Purpose of this Fast IFU

The purpose of this Fast IFU is to:

• support rapid printer setup and early calibration,
• provide practical starting parameters for DLP, LCD and MSLA workflows,
• introduce a fast CRT logic for selecting standard-layer exposure,
• help identify the most common causes of early print failure,
• accelerate onboarding before moving to the full IFU.

This document is designed for speed, clarity and practical implementation, not for exhaustive process qualification.

2) Scope and limitations

2.1 Scope

This Fast IFU applies to:

• DLP, LCD and MSLA vat photopolymerization printers,
• general-purpose, engineering and application-specific 3Dresyns® resin systems, unless a more specific IFU applies.

2.2 Not in scope

This Fast IFU does not apply to:

• laser-based SLA systems,
• inkjet, SLS or other non-vat technologies,
• regulated workflows unless validated separately,
• special systems requiring their own dedicated IFU.

2.3 System dependency

Performance, print quality and material behaviour depend on the complete material–printer–process–post-processing system, including resin version, real light power, exposure strategy, target Z layer thickness and post-processing workflow.

3) Standard starting settings for DLP, LCD and MSLA printers

These values are practical starting points and must be validated for each resin system, printer and application.

Interpretation rule: these values are not universal recipes. They are intended as a quick baseline from which the user performs structured CRT-based optimisation on the target machine.

4) Why exposure times are printer-specific

• Each printer has a different real light power at the vat.
• Light power may vary across the printable area.
• Light power decays with cumulative operating time.
• Different resin systems require different curing energies.
• Different target Z layer thicknesses require different cured depths.

As a result, generic exposure times are only practical approximations and cannot guarantee reproducible results across printers and over time.

Recommended background reading:

• Power differences of DLP, LCD & MLCD printers and their consequences
• Unlocking the black box of resin 3D printing

5) Fast CRT logic

The quickest structured way to choose a standard-layer exposure is to use a fast CRT.

Recommended fast CRT starting points: 5 s, 10 s and 15 s.

• Measure cured thickness at 5 s, 10 s and 15 s.
• Evaluate both cured thickness and green-state strength.
• Then add 1–2 extra points only in the interval relevant to the target Z layer thickness and printer power.

This is usually sufficient for rapid implementation because the initial adhesion layers can often be screened separately with 2–4 bottom layers at 75–100 s, while the main unknown is the correct standard-layer exposure.

How to extend the fast CRT

• For fast systems or higher-power printers, add points between 1 and 5 s or between 5 and 10 s.
• For slower resins, filled systems or lower-power printers, add points between 15 and 20 s or above.

6) How to choose the optimum exposure time

Select a standard-layer exposure that cures approximately the target layer thickness multiplied by an appropriate cure-thickness factor.

• Fast, brittle or highly reactive resins: typically start at approximately 1.0–1.2× the target layer thickness
• Slower, softer, less brittle or more peel-sensitive resins: typically start at approximately 1.3–1.5× the target layer thickness

Important note: these factors are approximate. Different resins may show different kinetic, mechanical, physical and adhesive behaviour and may therefore require different exposure margins.

• If the resin is fast and fragile, avoid unnecessary overexposure. Too much exposure may increase brittleness, increase adhesion to the FEP and increase the risk of breakage during separation.
• If the resin is slower, softer or less fragile, avoid under-curing. Too little exposure may leave the green part too weak to survive peeling.

Quick practical rule:

• Under-cured (soft, weak, too tender) → increase exposure
• Over-cured (too brittle, too much adhesion, loss of detail) → decrease exposure

7) Why CRT is more flexible than fixed parameter presets

A major advantage of CRT-based calibration is that it allows the user to re-optimise the same resin for different Z layer thicknesses depending on whether the priority is higher printing speed, higher Z resolution, improved dimensional control or a different balance between these variables.

• Need faster printing? Increase Z layer thickness and recalibrate exposure.
• Need finer resolution? Reduce Z layer thickness and recalibrate exposure.
• Need different workflows for different part types? Use the same resin with different validated CRT-derived settings.

This is one of the main advantages of CRT compared with workflows based on fixed parameter presets tied only to isolated Z-layer configurations.

8) Quick validation prints

• Download 3Dtest1 calibration STL file
• Download 3Dtest2 calibration STL file

8.1 Calibration step 1 — Print 3Dtest1 (flat coin, no supports)

This first fast test evaluates:

• general printability,
• XY resolution,
• appropriateness of the selected standard-layer exposure.

The coin includes concentric rings from 500 µm down to 2 µm. The smallest clearly resolved ring indicates the achievable XY resolution.

8.2 Calibration step 2 — Print 3Dtest2 (coin with supports)

This second test evaluates:

• support performance,
• XYZ printability,
• Z-axis accuracy after support removal.

Z-accuracy example: if printed thickness = 2.1 mm and nominal = 2.0 mm, relative Z error = 5%.

The support tips are intentionally thin to help evaluate minimum or near-minimum support contact size and the associated surface marking.

9) Interpreting failures (quick fixes)

• Part detached from build platform: increase bottom exposure time and/or the number of bottom layers.
• Part too soft or weak: under-cured → increase standard-layer exposure.
• Part too brittle or sticks excessively to FEP: over-cured → reduce standard-layer exposure.
• Poor XY detail but acceptable printability: reduce overcuring by lowering exposure and then re-check the calibration coin.

10) Basic tools for fast calibration

• digital calliper or micrometre,
• microscope glass slides,
• optional but recommended UV light meter for measuring printer irradiance.

11) Cleaning and post-processing

Final part performance depends not only on printing settings, but also on cleaning, drying and post-curing.

• Wash using the appropriate validated cleaning workflow.
• Ensure parts are fully dried before final post-curing.
• Follow the relevant resin-family or application-specific IFU where applicable.

12) Relationship to official Instructions for Use

This Fast IFU must always be used together with:

• Instructions for Use (IFU) & Printing Parameters for DLP & LCD printers
• any relevant printer-specific IFU,
• any relevant application-specific IFU, where applicable.

In case of discrepancy, the official IFU always prevails.

13) Governing principle

This Fast IFU provides practical guidance only. Final material performance depends on formulation version, real printer irradiance, exposure strategy, target layer thickness and post-processing workflow and must be validated by the user for the intended application.

14) Contact

For calibration support, CRT services or resin selection, contact info@3dresyns.com.