Resin print time calculator: layers, exposure and lift time

The formula

An MSLA (masked stereolithography) printer cures a whole layer at once through an LCD screen, then lifts the plate to peel it off the film and lowers it again. Every layer repeats that routine, so print time is the layer count times the seconds per layer:

layers      = print height / layer height
motion      = lift distance / lift speed + retract distance / retract speed
              (one term per stage; speeds in mm/min, so x 60 for seconds)
off time    = rest before lift + rest after lift + rest after retract + motion
total       = bottom layers     x (bottom exposure + off time)
            + transition layers x (average of bottom and normal exposure + off time)
            + normal layers     x (normal exposure + off time)

The CHITUBOX slicer’s docs time a single layer the same way: exposure time plus waiting time plus movement time.

• Transition layers step the exposure down in equal parts. CHITUBOX’s example: 4 transition layers between 25 s and 2.5 s get 20.5, 16, 11.5 and 7 s, so they average the midpoint. Elegoo’s manual says they share every other setting with the normal layers.
• Two-stage motion control (TSMC) lifts slowly to peel the layer, then fast. It retracts fast, then slowly over the last stretch. CHITUBOX requires the two retract distances to add up to the lift distance, so the calculator asks only for the slow final retract.
• Light-off delay is CHITUBOX’s legacy mode: one number covering lift, wait and retract. A delay shorter than the motion adds nothing.

The defaults are Elegoo’s Saturn 3 Ultra profile from its manual: 0.05 mm layers, 2 bottom layers at 35 s, 8 transition layers, 2.5 s exposure, a lift of 3 mm at 90 mm/min plus 4 mm at 320 mm/min, a retract at 320 mm/min with the last 1.5 mm at 90 mm/min, and a 1 s rest after retract. The Anycubic presets come from Anycubic’s recommended Photon Mono M5s parameters. Bottom layers use the normal motion here, as in both makers’ profiles.

The formula leaves out acceleration and the homing at the start. UVtools, an open-source tool for resin slice files, adds a flat 300 s to its estimates for the start. It also doesn’t fit printers whose firmware runs the release itself: Elegoo’s resin settings table gives no lift distance or speed for the Saturn 4 Ultra and Mars 5 Ultra, and UVtools counts 4 s of motion per layer for tilting-vat printers. Washing and post-curing come after the print and aren’t included.

How long does a resin print take?

A resin print takes its layer count times the seconds per layer, so height decides. With Elegoo’s default Saturn 3 Ultra profile, a 50 mm part at 0.05 mm layers is 1,000 layers and takes about 2 h 21 min. Each extra 10 mm adds about 28 minutes, so a 200 mm part runs 9 h 15 min.

Worked example with the defaults

1. Layers: 50 / 0.05 = 1,000, made of 2 bottom, 8 transition and 990 normal layers.
2. Lift: 3 mm at 90 mm/min is 2 s, then 4 mm at 320 mm/min is 0.75 s.
3. Retract: 5.5 mm at 320 mm/min is 1.03 s, then 1.5 mm at 90 mm/min is 1 s. Motion totals 4.78 s a layer.
4. Off time: 4.78 s of motion plus the 1 s rest after retract is 5.78 s a layer.
5. Exposure: 2 × 35 s = 70 s, plus 150 s for the transition layers (31.39 s down to 6.11 s), plus 990 × 2.5 s = 2,475 s. That is 2,695 s.
6. Total: 2,695 + 1,000 × 5.78 = 8,476 s, or 2 h 21 min.

Only 32% of that time is exposure. Moving the plate takes 56%, and resting takes 12%.

Print times by height

Print height	Elegoo Saturn 3 Ultra, 0.05 mm	Anycubic M5s, UV Sensitive Resin, 0.05 mm	Anycubic M5s, High Speed Resin, 0.1 mm
10 mm	31 min	24 min	5 min
25 mm	1 h 12 min	58 min	12 min
50 mm	2 h 21 min	1 h 55 min	23 min
100 mm	4 h 39 min	3 h 47 min	45 min
150 mm	6 h 57 min	5 h 40 min	1 h 8 min
200 mm	9 h 15 min	7 h 33 min	1 h 30 min

The High Speed column prints 0.1 mm layers, half as many as the other two. Anycubic pairs it with its high-speed resin and high-speed release film.

What makes a resin print take longer

• Height. Every 10 mm adds about 28 minutes at the defaults. Orienting a part lower cuts layers.
• Layer height. At 0.1 mm the 50 mm part has 500 layers and takes 1 h 12 min at the same exposure. At 0.025 mm it takes 4 h 39 min. Elegoo’s manual notes that thicker layers need longer exposure, so the real saving is smaller.
• Plate motion. Lifting and retracting take 56% of the time at the defaults. The same 7 mm up and down at a single 90 mm/min takes 9.33 s instead of 4.78 s, and the 50 mm part 3 h 37 min instead of 2 h 21 min. Two-stage motion saves that by moving fast once the layer is free.
• Rests. One extra second per layer costs 16 min 40 s over 1,000 layers: the default part grows to 2 h 38 min.

Resin print time for a miniature

Count the height the printer builds: figure, base and supports. A miniature that stands 40 mm above the plate takes 1 h 54 min with the Saturn 3 Ultra defaults, 1 h 32 min with Anycubic’s M5s standard profile and 18 min with its High Speed profile. A full plate of miniatures takes the same time as one. Scale names such as 28mm describe the figure, not the print height. The miniature scale calculator converts between scales.

Average resin print time

There is no useful average, because time follows height. A steadier figure is speed in millimeters per hour: the formula gives 21.2 mm/h for the Saturn 3 Ultra defaults, 26.2 mm/h for the M5s standard profile and 131 mm/h for its High Speed profile.

Anycubic quotes a 105 mm/h average for that last setup. That is 3.43 s a layer at 0.1 mm, against the formula’s 2.7 s. The 0.73 s difference is time the slicer settings don’t show.

How do you calculate resin print time?

Divide the print height by the layer height to get the layer count. Each layer takes its exposure plus lift and retract time plus any rests. Motion time is distance divided by speed, times 60 for speeds in mm/min. Bottom layers use the longer bottom exposure, so add them separately.

Where to find each setting

Copy each value from your slicer’s print settings. The names differ:

Calculator	CHITUBOX	Lychee	Elegoo manual	Anycubic
Rest before lift	Rest Time Before Lift	Wait After Print	Wait Before Lift
Rest after lift	Rest Time After Lift	Wait After Lift	Wait After Lift
Rest after retract	Rest Time After Retract	Wait Before Print	Wait Before Cure	Off Time

• Print height: the tallest point above the plate, supports and raft included.
• Speeds: CHITUBOX shows mm/min. Anycubic lists mm/s, so its 6 mm/s is 360 mm/min. Lychee’s guide says Anycubic’s single delay works like Wait Before Print.
• Two-stage lift: CHITUBOX shows two lift fields and two retract fields. Enter the second retract field as the slow final retract. The first is whatever remains of the lift.
• Check against a real print: Lychee suggests timing layers with a stopwatch. CHITUBOX turns the gap into a per-layer correction: (actual time minus estimated time) / layer count.

Resin print rest time and off time

Rests add straight onto every layer. Elegoo’s Saturn 3 Ultra profile rests 0 s before lift, 0 s after lift and 1 s after retract. Anycubic’s M5s profiles use a 0.5 s off time.

CHITUBOX calls the rest after retract relatively critical, since it lets the resin settle before the next exposure. Lychee’s guide calls Wait Before Print the most critical wait and says Wait After Print may only add time.

In legacy light-off delay mode, the off time is one number: lift time plus retract time plus wait. The defaults’ equivalent is 5.78 s. Any delay at or below the 4.78 s of motion changes nothing. CHITUBOX’s own example lifts 7 mm at 70 mm/min (6 s), retracts at 210 mm/min (2 s) and waits 2 s, for a 10 s delay.

Is resin printing faster than FDM?

It depends on the job: resin time follows height, while fused deposition modeling (FDM) time follows the plastic laid down. One 3DBenchy takes about 48 minutes on a Bambu Lab A1 mini and 2 h 16 min with the Saturn 3 Ultra defaults. With three or more on the plate, resin finishes first, because extra copies add no time.

A resin printer exposes every part on the plate in one shot. Formlabs credits curing each layer all at once as the biggest factor in its MSLA printer’s speed. An FDM printer traces each part with its nozzle, so its time grows with the plastic, as the print time calculator works out. The 3DBenchy is 48 mm tall, so it prints 960 resin layers at 0.05 mm.

Benchies on the plate	FDM, Bambu Lab A1 mini, 0.20 mm	Elegoo Saturn 3 Ultra, 0.05 mm	Anycubic M5s, 0.05 mm	Anycubic M5s High Speed, 0.1 mm
1	48 min	2 h 16 min	1 h 50 min	22 min
2	1 h 36 min	2 h 16 min	1 h 50 min	22 min
3	2 h 24 min	2 h 16 min	1 h 50 min	22 min
5	4 h	2 h 16 min	1 h 50 min	22 min
10	8 h 1 min	2 h 16 min	1 h 50 min	22 min

The FDM column multiplies Igor’sLAB’s timed 48 min 3 s Benchy. Several copies on one plate also add travel moves between parts, so treat it as the low end. The comparison isn’t like for like: the FDM Benchy uses 0.20 mm layers, four times thicker than the 0.05 mm resin layers.

On these figures, the FDM printer beats both 0.05 mm resin profiles on a single Benchy, and every resin profile beats it from three copies up. Run both calculators on your own part to compare.