About 3Dresyns calibration files for maximum control of resolution and printing speed

3Dresyns calibration files and protocols help you achieve maximum control of resolution and printing speed. Depending on your objective, you can balance both, or prioritise resolution at the expense of speed (or vice versa).

3Dresyns® is, to our knowledge, the first and only materials-driven company providing calibration methodology that explicitly evaluates dimensional accuracy in the three spatial axes: X, Y and Z. Many publicly available calibration files focus primarily on XY feature visibility, but functional 3D parts require verification and control of XYZ dimensional accuracy.

Key references:

• Instructions for Use (IFU)
• Curing Rate Tables (CRT)
• 3Dresyns® Curing Rate Control System
• Structured Calibration & Dimensional Control in Vat Photopolymerization
• 3Dresyns calibration files
  • Download 3Dtest1 calibration STL file
  • Download 3Dtest2 calibration STL file

Light power variability & power decay (why settings drift)

Depending on the chosen 3D printer—its optical design, wavelength, nominal irradiance, power distribution across the vat, and cumulative operating time—the real (effective) light power available for curing can vary significantly and will typically decay with use. This directly impacts exposure settings and printing reproducibility.

Why light power changes over time

Any light source (laser, LED, lamp) experiences a natural reduction of output over time. In LCD printers, the LCD panel itself does not emit light, but its light transmittance degrades with UV exposure and heat. LCD panels act as a mask: an LED array provides backlight and the panel selectively transmits or blocks light to define each layer.

Multicolor LCD panels are generally more sensitive to UV/thermal degradation than monochrome LCD panels, which is why they tend to require replacement more frequently.

Typical lifetime and decay trends

The chart below illustrates typical light output decay versus cumulative operating time for common systems used in SLA, DLP and LCD printers.

• LED projectors can have long lifetimes (often > 15,000 hours), but still show gradual output decay over time.
• Lamp-based DLP projectors typically degrade faster than LED projectors.
• Monochrome LCD panels generally last longer than multicolor LCD panels.
• Multicolor LCD panels may have short lifetimes (often a few hundred hours) and are usually treated as consumables.

Bottom line: lack of power control, monitoring and compensation is one of the main causes of printing frustration, failed builds and quality variability.

Why “generic exposure settings” are often wrong

Exposure recommendations for “generic printer types” are inevitably too broad because exposure depends on real irradiance at the resin surface. As a rule: lower real power → longer exposure time (for the same resin, layer thickness and target cure depth).

Even among printers of the same model, “new out of the box” units can show 10–20% power differences due to small optical and configuration variations, which changes the optimum settings. For more detail: Power difference of DLP, LCD & MLCD printers and its consequences.

And because power decays with operating time, printers (including plug & play systems) will eventually require longer exposures to cure the same resin at the same layer thickness.

Optional: CRT and power matching for higher accuracy

The CRT provides a practical calibration reference: cured thickness of the selected resin at defined exposure times, under controlled conditions. If you share your measured printer power, CRT measurement can be aligned to a matched irradiance condition, improving accuracy and reducing setup time.

If you want a structured workflow for DLP/LCD printers, see: Fast and accurate IFU for DLP & LCD printers.

3Dtest1: fast printability + XY resolution + baseline Z control (coin without supports)

3Dtest1 is a coin printed without supports, directly on the build platform. It provides a fast proof of printability for a 2 mm nominal thickness part, for example:

• 20 Z layers at 100 microns, or
• 40 Z layers at 50 microns.

This test provides a first indication of XY resolution, because the coin contains concentric circles with defined width and depth. The concentric line set includes:

• 500 microns (0.5 mm), then 400, 300, 200, 150, 100, 80, 60, 40, 20, 10, 5, and 2 microns.

The thinnest clearly visible circle is a practical indicator of achievable XY resolution with the selected resin and printing settings.

Baseline Z control: because the coin has a nominal thickness of 2 mm, the printed thickness provides an early indication of Z drift (overcure / secondary curing trends), even before moving to supported geometries.

If 3Dtest1 fails: diagnose the failure stage

A) The whole coin detaches from the build platform

• Increase the bottom exposure time and/or the number of bottom layers to improve adhesion to the build platform.

B) The coin is partially printed, but part remains stuck to the build platform

Adjust the normal exposure time in small increments (a few seconds), based on the mechanical feel and fracture behaviour of the printed section:

• Increase exposure time if the printed area left on the platform is too tender (undercured) and breaks or tears easily.
• Decrease exposure time if the printed area left on the platform is too brittle (overcured) and shows excessive rigidity or breakage.

3Dtest2: printability with supports + robust XYZ assessment

Once the coin prints without defects, proceed with 3Dtest2 (the same coin with supports). This confirms printability under supported conditions and provides a more sensitive assessment of XYZ behaviour under peel forces and constrained resin renewal.

Why 3Dtest2 is intentionally demanding: the planar supported geometry is designed to retain resin between supports with limited resin refresh during printing, simulating worst-case “pseudo-lakes” found in real parts. In such regions, resin may receive a cumulative stray exposure dose, leading to delayed secondary curing and progressive local thickening (often visible as increased Z thickness or feature growth behind supports).

How to estimate Z dimensional deviation

Z accuracy can be estimated by comparing measured printed thickness to the nominal value. For example, if the printed thickness is 2.1 mm and the nominal thickness is 2.0 mm:

Dimensional deviation (%) = (2.1 - 2.0) × 100 / 2 = 5%

Support tip design

The support tips (connections) are deliberately thin (0.8 mm) to simulate real printing constraints, including minimal-support strategies and filigree parts, while reducing visible marking after support removal.

When to use fine-tuning additives (FT & LB series)

After exposure optimisation, fine-tuning additives may be used for controlled directional adjustment:

• FT series to increase curing rate and enable faster printing when validated by the user: Photo-accelerants (FT collection)
• LB series to reduce scattering, bleeding and cumulative overcure for higher resolution and improved dimensional control: Light blockers (LB collection)

Fine-tuning additives are used in small, incremental steps. Reprint 3Dtest1 and 3Dtest2 after each change and document the additive, dosage and resulting dimensional shift. Results are printer-dependent and must be validated by the user.