Tag Archives: MSLA

MSLA Anycubic Photon Mono X2


  • 2023/07/25: published
  • 2023/06/13: adding my print settings to increase reliability
  • 2023/03/31: first prints performed
  • 2023/03/29: adding Formlabs 3/3L and Prusa SL1S as comparison
  • 2023/03/23: starting write-up


After my first steps with Anycubic Photon Mono 4K, an entry-level MSLA I also got a slightly larger Anycubic Photon Mono X2:

  • build volume: 196 x 122 x 200 mm (WxDxH)
  • resolution: XY 48μm, Z 50μm
  • 9.1″ display with 4K+ resolution (4096×2560) display
  • monochromatic LCD (hence “Mono”), faster printer due shorter exposure
  • affordable with EUR 300-350 (2023/03)
  • no network, only USB drive printing

I ordered at Anycubic.com directly (EUR 350) 2023/03/24, and got it a week later.

Default Settings

Firmware V0.2.3
My Settings
My Settings
Bottom Layers651 .. 6 2)
Exposure Off [s]1.0
Bottom Exposure [s]
Normal Exposure [s]
Transition Layers41010
Bottom Region
Bottom Layer [0] Rising Height [mm]3.04.0
Bottom Layer [0] Rising Speed [mm/s]1.0
Bottom Layer [0] Retract Speed [mm/s]1.0
Bottom Layer [1] Rising Height [mm]4.04.0 1)
Bottom Layer [1] Rising Speed [mm/s]
Bottom Layer [1] Retract Speed [mm/s]3.0
Normal Region
Normal Layer [0] Rising Height [mm]3.04.0
Normal Layer [0] Rising Speed [mm/s]1.0
Normal Layer [0] Retract Speed [mm/s]1.0
Normal Layer [1] Rising Height [mm]4.04.0 1)
Normal Layer [1] Rising Speed [mm/s]
Normal Layer [1] Retract Speed [mm/s]3.0
UV Light (not available)
  1. in Lychee Slicer the 2nd lift distance is the sum of [0] Rising Height 4.0mm + [1] Rising Height 4mm = “4.0mm > 8.0mm”:
  2. depending on the size of the pieces, if they are small (e.g. 20x20mm foot print) then I use 1 bottom layer, for larger pieces I increase up to 6 bottom layers

After some prints I realized the 3mm/s or 180mm/min 2nd rising speed really decreased the reliability of prints I did, usually after bottom layers some models, especially fine structures, deliminated and I realized the transitioning needed to be longer and also reduce the 2nd rising speed, the retraction speed could stay as is. The slowed down the overall print time, but reliability is getting near to Mono 4K.

Various Resins

from Anycubic Web-Site (2023/04/02)

Mono 4K vs Mono X2 vs Mono M3 Max

The print area Mono 4K doubles nearly with Mono X2, and the Mono M3 Max (EUR 1000) additionally doubles the print area:

As pointed out previously, the print area with MSLA directly affects the print speed, the larger the build plate, the faster the print: more parts can be printed at the same time.

The Mono X2 is relatively new as of writing this blog-post, just released in late 2022, so the third party market has not yet taken off regarding spare vats, spring steel magnetic build plate, protective films and alike.

Update 2023/07: The Mono X2 already discontinued as M5 and M5S has been released.

Photon Mono X2 vs Creality LD-006: Details Matter

The main reason I prefered the Photon Mono X2 (EUR 350) over the Creality LD-006 (EUR 250) with the nearly same build-volume is that the LD-006 has a bad build-plate mount where resin is trapped near the screws – which makes cleaning and switching resins much harder:

Eventually either cured, dried or semi liquid resin trapped in there will contaminate your next prints – so a bad build plate design can ruin your prints eventually.

Slicer Support

Lychee Slicer 5.x and upward also supports the Mono X2 out of the box, whereas Prusa Slicer SLA slicer, as of 2.x series, does not slice to any but .sl1, and so requires a custom setting to add support for it indirectly then requires a tool like UVtools to convert to .pmx2 (Note: as of 2023/03 the output format is not working properly).

The native Photon Workshop slicer coming with the printer has no Linux support and only works via Wine “Windows” emulator, and is barely usable.

Printing 40x Triply Periodic Minimal Surfaces 20mm cubes samples at once, and it took 1h45m (with default settings) with apprx. 30mm height, as some required support.

The pieces were overexposed, the bottom layers were significantly overexposed, the clear resin as well the white resin which came as 2nd batch – the defaults as recommended by Anycubic and consequently by Lychee Slicer 5.1.8 were not as good as Photon Mono 4K.

The default settings with 3mm/s or 180mm/min for 2nd lift speed caused multiple failed prints for me such as delimination, and I reduced it to 1.5mm/s or 90mm/min and increased transitioning layers from 4 to 10 – after that fine structures like those 40mm cube lattice prints came out quite well.

Photon Mono X2 Drip Hook

I highly recommend a drip hook, you want uncured resin easily drip over a period of 5-10min back into the vat, before you wash it off in water (when using water wash resin) or isopropyl alcohol (IPA).

Photon Mono X2 Drip Hook

Third Party Market

Photon Mono X2 compatibilitySpecifications
vatPhoton Mono X, Mono X 6K, Mono M3 Plus263 x 169 x 30 mm (outside max)
238 x 162 mm (inside)
steel build plateElegoo Saturn S (same LCD size)202 x 129 mm (min. 196 x 122mm)

Spring Steel Plate

I made two prints with the original build plate, and it was difficult to remove the prints without flexing and scratched the plate right away – the adhesion is good, too good actually. So it became clear, I also want a spring steel plate for it.

I’ve got a spring steel plate 202×128 mm from Aliexpress.

  • magnetic base: 2.2mm thick, slightly extends, 203x129mm
  • steel plate: 0.5mm thick, exact 202x128mm

so one has to compensate 2.5 – 3mm in Z height and adjust, speak extend, the Z-level probe. I just glued a black strip of paper, and then of course re-level the bed again afterwards.


The motherboard has two main chips:

  • ARM GD32F407
    • driving Z stepper motor with endstop (Z=0)
    • driving USB port
    • driving both LCDs via ASIC
  • EF2L 45L G1444B (ASIC)
    • driving monochrome LCD via MIPI DSI (not sure where the image buffer resides)
    • driving UI color LCD with touchscreen
Mono X2 motherboard

Preliminary Review Mono X2


  • good value for build size, but not features
  • mid-size build volume with 196 x 122 x 200 mm (WxDxH)
  • no cover sensor (can be on or off and still prints)
  • available replacement of parts (LCD, vat, build-plate)


  • no Wi-Fi (only USB Stick)
  • surprisingly noisy with fans while printing
  • firmware doesn’t allow to change UV light intensity
  • default settings are not giving reliable prints1)
  • very simple firmware & UI
  • no flex build plate
  • no upper endstop (you can ramm the build-plate into the plate on top)
  • no sensor for running plate against cured remains in vat2), that would require more advanced firmware
  • cheap USB memory stick (breaks after a few days, data corruption)
  1. using original Anycubic Water Washable Resin +
  2. newer printers (2023) have load cell to measure counter force, and prevent build-plate to run with force against vat and LCD underneath. Update 2023/05: Anycubic released Mono M5S (2023/05) which has a load-cell sensor, but reviews are mixed.
Photon #4 (Mono X2) & Photon #1 & #2 (Mono 4K): additional handle on top, and labels on cover and body


Printing Procedure

Let me take the chance to describe my MSLA resin printing procedure – if you are newcomer you might like to read it in a concise way.

  • resin printing (as in 2023) is still a messy procedure at the consumer and prosumer level as well
  • the moment the print is finished, you need to remove the build-plate or flex steel plate, no matter which, the piece(s) still have resin on it, which likely will drip on the printer and especially around the vat is the most critical area:
    • by any means prevent any resin to come under the vat
    • don’t touch the underside of the vat with hands or gloves, unless you have a fresh piece of sheet of paper towel or equivalent
    • if you must clean the underside of the vat – and if you do you already screwed up when this happens – clean it first thoroughly, and after that the side of the vat and other part of the printer
    • prevent any resin to get on the LCD or protective layers on the LCD, wipe it away right away
    • cured resin is difficult to remove, especially from softer surfaces like plastic – so I have the habit to remove all resin outside of the vat right away
  • clean your gloves with pieces of paper towel, to prevent to further spoil your equipment you grab as next:
    • clean gloves when handling the build plate
    • I keep the same gloves for multiply prints or a 1-2 weeks as I clean them with paper towels right away (2-3 times per print: whenever I touch the 3d printer, the gloves are clean)
  • when removing the pieces from the build plate, things will become messy, no matter what
  • washing the piece(s) off in a water container as I use only water wash resin
    • 1st wash container: I dip the pieces with the build plate into the container, my gloves don’t get wet or touch resin
    • 2nd wash container: I remove the flex build plate, and dip it with the pieces still on the plate into the 2nd container – dipping in and out several times
  • then I remove the pieces from the flex build plate, by flexing the build plate or use a metal scrapper, and they drop into a small container with layers of paper towels where they dry a bit (10-30min) – I don’t touch the pieces with my gloves, I only touch the build plate
    • cleaning the build plate with paper towels dry, mount it back on the printer
    • cleaning the flex build plate with paper towels and attach it to the build plate
  • no cured remains in vat: using the plastic scrapper to push on the vat’s bottom softly, and move through the vat slowly to see if there are remains attached to the vat bottom, those needs to be removed otherwise at next print the build plate will push it unto the LCD and potentially damage it – high risk to damage the MSLA printer severely, such as puncture FEP of the vat and leak resin all over
    • if there are cured remains on the bottom FEP which I can’t remove with the plastic scrapper (large enough to pick out), then
      • either I expose the entire plate for 10-20s, and remove then a full cured layer of the entire area, this removes all small remains
      • if there are small floating pieces, then I empty the vat off the resin by pouring through a metal or paper filter (keeps back remove all cured remains) back into the bottle – this is time consuming and messy as you need to clean funnel and metal filter again
  • if I have printed pieces with small holes where water might still be captured, I take a piece of paper towel and wrap it and shake it fast in my hands – I have seen people blowing compressed air on the cured pieces, this makes sense if you produce many pieces in series frequently
  • 2nd stage curing of the pieces in UV chamber:
    • white/black/grey resin 1-3 mins
    • clear resin 2 mins max
  • further resting the piece(s) for 1-2 hours to dry further

And I leave the resin in the vat, and let the vat stay on the printer for days – no refilling back and forth to and from bottles, unless I know I have cured fragments in the vat, then I empty the vat with metal or paper filter back into the bottle and clean it with paper towels thoroughly as mentioned above already.

Keep everything around MSLA printer as clean as possible.

Consumer MSLA vs Professional SLA

When trying to compare consumer MSLA and professional SLA like from Formlabs you might just look at the print size or build volume:

but also look at other aspects:

Photon MonoPrusa SL1SFOrmlabs Form 3, 3L
PricingEUR 200-1,000EUR 2,000EUR 5,000-10,000
TechnologyMSLAMSLALow Force SLA
Exposure TechnologyUV light with monochrome LCD (4K)UV light & monochrome LCD (2K)UV laser
Automaticsresin levelresin level
resin dispenser
resin heating
level indication
Next Layer Methodpeeling with 2 stage raisingpeeling by tiltingpeeling & wiping
Removal of Partmessymessy without CW1
OK with CW1
messy without Form Wash
OK with Form Wash3)
Cleaning Partmessymessy without CW1
OK with CW1
messy without Form Wash
OK with Form Wash3)
Post Curing Partrequiredrequiredoptional
Slicing Software★★☆☆☆ Photon Workshop
★★★★☆ Lychee Slicer
★★★★☆ Prusa Slicer★★★★★ PreForm
Print Speed★★★★☆
depends only on print height
depends only on print height
depends on layer cross section &
print height
Hardware Maintainability★★★☆☆★★★★☆★★★☆☆
Original Online Resources★☆☆☆☆★★★★★★★★★★
Community Resources★★★★☆★★★★☆★★★☆☆
After Sales Support★★☆☆☆★★★★☆★★★★☆
Third Party Market★★★☆☆★★☆☆☆☆☆☆☆☆
  1. based on overall build and firmware, which can’t even properly calculate remaining print time while printing, I have a low expectation
  2. value for all is the same, because the low price for Anycubic Photon Mono series also give you moderately good solution, whereas Formlabs printers are very pricey but also giving you good value, and Prusa SL1S rather high priced for the gaining reliability and print speed
  3. Form Wash station for Form 3, Form Wash L for Form 3L, you move the build plate direct into the washing station, and before curing remove them from the build plate
  4. Prusa SL1S prints a layer in 2 seconds in total, whereas traditional MSLA takes 7-10s (exposure time + lifting/retraction)

As a follow-up, while reviewing another resin printer, I realized the “value” for me I could actually determined by the XY area which translate into parallel printing capability, which is more relevant than the height (Z), combined with the precision or voxel size – as of 2023 Anycubic doesn’t even mention the XY resolution anymore – a bad marketing move.

(M)SLA Value Comparison

A numeric value summarization for features I care about:

Formula: XY Area [cm2] / Price [EUR] / (XY Resolution [μm] * 10): the bigger the XY area, the smaller the price and the smaller the resolution.

State 2023/11

Photon Mono M519μm x 24μm2)MSLA218x123x200410 EUR2.72
Photon Mono X 6Ks34μmMSLA196x122x200280 EUR2.51
Saturn 3 Ultra19μm x 24μm2)MSLA218x123x260480 EUR2.32
Photon Mono 4K d/c35μmMSLA132x80x165150 EUR2.07
EMake Galaxy 125μm / 100μm1)SLA400x200x4001,600 EUR2.00
Photon Mono X248μmMSLA196x122x200260 EUR1.91
Photon Mono 235μmMSLA143x89x165210 EUR1.73
Photon M3 Max45μmMSLA298x164x300980 EUR1.10
Formlabs 3L25μm / 100μm1)SLA335x200x3009,000 EUR0.18
Formlabs 3+25μm / 100μm1)SLA146x145x1853,500 EUR0.15
Prusa SL1S49μmMSLA127x80x1801,700 EUR0.12
  • d/c = discontinued
  1. Formlabs & EMake SLA printers use a laser beam which has 100μm in diameter, but it can be positioned 25μm exact, the latter was used to calculate the value
  2. The UV pixels are non-square, the longer side was used to calculate the value

The XY area in SLA scales not as good as with MSLA, as the laser beam takes longer the more XY area (e.g. more pieces) need to be rendered per layer – so, MSLA is recommended for aiming fast parallel printing.

That’s it.


MSLA Anycubic Photon Mono 4K


  • 2023/07/25: moved content from blog into regular pages
  • 2023/03/15: adding more Settings for different resins, different default for different firmware version, added preliminary Review
  • 2023/03/09: finally published
  • 2023/03/05: first prints made, more info on Lychee Slicer, Prusa Slicer SLA, more on magnetic steel plate use, prints with or without support, closeup photos added
  • 2022/11/29: added Drip Hook, still preparing the utilities to make first print
  • 2022/11/26: Mono 4K arrived, preparing software pipeline (slicer, converters) and working place
  • 2022/11/07: starting write-up


The past years I focused on Filament Deposition Manufacturing (FDM) / extrusion based 3D printing, and the time came to focus on MSLA resin based process as well.

My main use case a small pieces, like custom pulleys and idlers – precise parts, such as:

Anycubic Photon Mono 4K

The Anycubic Photon Mono 4K seemed like a good choice to start with:

  • build volume: 132 x 80 x 165 mm (WxDxH)
  • resolution: XY 35μm, Z 50μm
  • 6.1″ display with 4K resolution (3840×2400) display
  • monochromatic LCD (hence “Mono”), faster printer due shorter exposure
  • affordable with EUR 170-220 (2022/11)
  • no network, only USB drive printing
Stereolithography Apparatus
– one beam/point light source
Mask Stereolithography Apparatus
– one light source, masking what does not need to be printed
Digital Light Processing
– one image, each pixel controlled by micro mirror

I ordered 2022/11/22 for EUR 170 and received it 4 days later via Anycubic Store within Amazon, along with a few utilities like water wash resins, gloves, etc – ready to MSLA print.

Update 2023/05: the Mono 4K has been discontinued, and replaced with Mono 2 with slightly larger print volume of 143 (+11mm) x 89 (+9mm) x 165 (+33mm).

FDM/FFF vs Resin

X, Y precision: 100μm
Z precision: 50μm
minimal structure: 200-600μm1)
minimal post-processing
minimal toxicity of filament
print duration based on printed volume
large scale prints affordable
1kg filament EUR 15-30
mixed materials2)
X, Y precision: 35-75μm
Z precision
: 30-50μm
minimal structure
: 30-50μm
extensive post-processing
severe toxicity of resin
print duration based on print Z height only
large scale prints require expensive printers
1kg resin EUR 30-803)
single material
  1. depends on nozzle diameter
  2. multiple printheads/hotends required, e.g. IDEX, tool changer, material changer
  3. Anycubic sold water wash resins at 22-27 EUR/kg 2023/03 (black, white, clear, grey and waterblue)

Print Settings

  • layer height: 0.05mm / 50μm
  • exposure time: 2s
  • light-off time: 0.5s
  • bottom layer count: 6
  • bottom exposure time: 40s
  • lifting distance: 6mm
  • lifting speed: 4mm/s
  • retract speed: 6mm/s
  • anti-aliasing level: 1
  • file formats: pwma (proprietary)

Photon Workshop on Linux

My development environment is Linux, and as of 2022/11 there is no Linux Photon Workshop, the name of the slicer needed to slice for Mono 4K; but you can run it via Wine (a Windows compatibility wrapper):

% wine AnycubicPhotonWorkshop_V2.2.19_x86.exe

and afterwards it is available direct at:

% wine ~/.wine/drive_c/Program\ Files\ \(x86\)/AnycubicPhotonWorkshop/AnycubicPhotonWorkshop.exe

I tried my xyzHollowCalibrationCubeV2 and used auto hollow feature which defaults to 2mm thickness:

This seems to work but is not ideal. The Photon Workshop reveals that Photon Mono 4K supports only .pmwa format, which as it turns out, is PWS format just with the extension .pmwa to avoid mixing up different PWS files for different machines, as the pixel-based slices are hardware dependent now as resolution of the display is set.

Chitubox for Linux

Chitubox Slicer is available for Linux natively and supports a variety of SLA printers, also the Mono 4K:

I also used the auto hollow feature, which defaulted to 1.2mm wall thickness.

Lychee Slicer for Linux

I ended up with the Lychee Slicer which is available for Linux as well, which contains some annoying advertising to wait for when slicing or exporting various formats, but functionality-wise it it is more intuitive than Chitubox Slicer.

Prusa SLA Slicer

As mentioned, the Photon Mono 4K has its own proprietary file-format PWS file to print with, with a particular file extension to indicate which Anycubic MSLA device it is sliced for:

MachineFile ExtensionLayer Image Encoding

Prusa Slicer slices also for MSLA, it’s own .sl1 format, just a ZIP file with a list of PNG files per slice, in order to convert .sl1 to PWS/.pwma another tool is required:

  • UVtools, it can read and write many SLA image formats, incl. PhotonWorkshop (.pw*) file-formats
  • another approach could be (as of 2022/12 not yet) to just convert sl1 to .photon with SL1toPhoton command line tool, and extend functionality to support PWS/.pwma as well
  • alternatively uv3dp supports pw0 and pws files, but struggles with new(er) PWS files like .pwma

.photon/ctb/cbddlp vs .pw*

.photon (and ctb/cbddlp) is an older file format, whereas newer Photon Workshop (PW) has PWS and PW0 encoded images as layers – so far the format seems reverse engineered and somewhat documented via UVTools: PhotonWorkshopFormat.cs

ManufacturerFile ExtensionFIle FOrmat
Anycubic Photon Mono.pw*PWS/PW0
Anycubic Photon.photonalike CTB
Elegoo Mars.ctbCTB/CBDDLP1)
Creality LD002.ctbCTB/CBDLP1)
  1. possibly encrypted, but the algorithm is available

PWS vs SL1

Some deeper dive into the available metadata of PWS vs SL1 format:

PWS (header)SL1 (prusaslicer.ini)
“xy_pixel”: 35.0,
“z_thickness”: 0.05000000074505806,
“exposure_time”: 2.0,
“off_time”: 0.5,
“bottom_layers_exposure_time”: 40.0,
“bottom_layers”: 6.0,
“z_lift_height”: 6.0,
“z_lift_speed”: 4.0,
“z_drop_speed”: 6.0,
“total_volume”: 4.853200912475586,
“antialiasing_grade”: 1,
“x_resolution”: 3840,
“y_resolution”: 2400,
“weight”: 0.0,
“price”: 1.067704200744629,
“resin_type”: 36,
“layers_count”: 400

“absolute_correction”: “0”,
“area_fill”: “50”,
“bed_shape”: “0x0,120×0,120×68,0x68”,
“bottle_cost”: “0”,
“bottle_volume”: “1000”,
“bottle_weight”: “1”,
“display_height”: “68”,
“display_mirror_x”: “1”,
“display_mirror_y”: “0”,
“display_orientation”: “portrait”,
“display_pixels_x”: “2560”,
“display_pixels_y”: “1440”,
“display_width”: “120”,
“elefant_foot_compensation”: “0”,
“elefant_foot_min_width”: “0.2”,
“exposure_time”: “10”,
“faded_layers”: “10”,

“fast_tilt_time”: “5”,
“gamma_correction”: “1”,
“hollowing_closing_distance”: “2”,
“hollowing_enable”: “0”,
“hollowing_min_thickness”: “3”,
“hollowing_quality”: “0.5”,
“initial_exposure_time”: “15”,
“initial_layer_height”: “0.3”,
“layer_height”: “0.3”,

“material_correction”: “1,1,1”,
“material_correction_x”: “1”,
“material_correction_y”: “1”,
“material_correction_z”: “1”,
“material_density”: “1”,
“material_print_speed”: “fast”,
“max_exposure_time”: “100”,
“max_initial_exposure_time”: “150”,
“max_print_height”: “200”,
“min_exposure_time”: “0”,
“min_initial_exposure_time”: “0”,
“output_filename_format”: “[input_filename_base].sl1”,
“pad_around_object”: “0”,
“pad_around_object_everywhere”: “0”,
“pad_brim_size”: “1.6”,
“pad_enable”: “1”,
“pad_max_merge_distance”: “50”,
“pad_object_connector_penetration”: “0.3”,
“pad_object_connector_stride”: “10”,
“pad_object_connector_width”: “0.5”,
“pad_object_gap”: “1”,
“pad_wall_height”: “0”,
“pad_wall_slope”: “90”,
“pad_wall_thickness”: “2”,
“printer_technology”: “SLA”,
“relative_correction”: “1,1”,
“relative_correction_x”: “1”,
“relative_correction_y”: “1”,
“relative_correction_z”: “1”,
“slice_closing_radius”: “0.049”,
“slicing_mode”: “regular”,
“slow_tilt_time”: “8”,
“support_base_diameter”: “4”,
“support_base_height”: “1”,
“support_base_safety_distance”: “1”,
“support_buildplate_only”: “0”,
“support_critical_angle”: “45”,
“support_head_front_diameter”: “0.4”,
“support_head_penetration”: “0.2”,
“support_head_width”: “1”,
“support_max_bridge_length”: “15”,
“support_max_bridges_on_pillar”: “3”,
“support_max_pillar_link_distance”: “10”,
“support_object_elevation”: “5”,
“support_pillar_connection_mode”: “dynamic”,
“support_pillar_diameter”: “1”,
“support_pillar_widening_factor”: “0”,
“support_points_density_relative”: “100”,
“support_points_minimal_distance”: “1”,
“support_small_pillar_diameter_percent”: “50%”,
“supports_enable”: “1”


  • PWS:
    • xy_pixel dictates square pixels
    • x_resolution & y_resolution with xy_pixel give actual build area
    • build height (Z) determined via layers_count * z_thickness, assuming equal layer heights
  • SL1:
    • does not report layer counts, but be determined from the amount of enclosed .png files
      • does not support multi-exposure printing
x_resolution [px]display_pixels_x [px]
y_resolution [px]display_pixels_y [px]
xy_pixel [μm]display_pixels_x / bedshape[x] * 1000 [μm]

Replacing Firmware

MSLA resin printers are quite closed systems without much information of the hardware, firmware, and additional having their own proprietary file formats which contain the layer images.

For the Anycubic Photon Mono 4K is an open source firmware available, Turbo Resin – which gave me a good reason to get this 3D printer (2023/07: the firmware isn’t complete yet). Along with it, the hardware has been pretty much reversed engineered.

Anycubic FirmwareTurbo Resin (2022/12)
– PW0/PWMA format– PW0/PWMA & CTB format

Custom MSLA Slicer

Pondering on a custom MSLA slicer:

  • automatic hollowing of solids at certain wall thickness
  • automatic support generation, outside and inside (after hollowing)
  • drain hole generation
  • command line interface (CLI)
  • external preview of sliced part
  • supporting sl1 and pws/pw0 as a start
FeaturePrusa SlicerLychee SlicerChituBox Slicer
command line interface (CLI)Y
automatic hollowingYYY
drain holesYYY
automatic supportYYY
Linux supportY
PWS supportYY

Open MSLA Format

Unfortunately there is no open (M)SLA format, each manufacturer kind of does its own, whereas G-code .gcode has some conformity, although G-code in general is also machine specific has it has absolute positioning, which differ from machine to machine, but at least G-code is easy to compose unlike proprietary (M)SLA file formats.

SL1 format by Prusa Engineering is a simple ZIP file which contains:

  • config.ini: irrelevant info
  • prusaslicer.ini: info about printer (bed size), pixel density, and many slicer settings
  • *.png: enumerated image files per slice in PNG format

and thereby is open enough for my taste.

Requirements of Open MSLA Format

  • simple format for controller to decode
    • simple pixel data1)
    • simple preview image format1)
  1. this is why PWS/PW0 or CTB fileformat use some simple RLE algorithm to compress pixel data

First Print

After many weeks postponing, as I wasn’t eager deal with the inherent messiness of resin printing, I gave it a shot with some of the Triply Periodic Minimal Surfaces (TPMS) (2023/03/05):

The Lychee Slicer gave 1h 15m print time, the printer itself showed 2h 15m; I used Anycubic White Water Wash Resin. I used automatic supports, and it printed 5 pieces successful, 3 pieces failed and only apprx. 4mm Z height were printed, interestingly all 3 failed pieces failed at the same Z height and broke off and stuck at the print plate.

I reprinted the 3 failed pieces at the same place, and this time they succeeded – which is strange as I suspected perhaps uneven light or some other positional inconsistency, but obviously the position did not matter, which is bad as I don’t know what caused the first failed print.

The curved bottoms (not directly printed but with diverse support pipes) already showing severe distortion while printing.

Update: It seems my office rooms aren’t warm enough, so the bed adhesion isn’t optimal as I read up in some forum posts. I tried to print a few other pieces, all failed the next day in the room with 15-19C° – the prints detached after 2-3mm height from the build plate. I moved it to another warmer room, warmed the resin on the radiator which helped.

The overall quality of the pieces is astonishing, no visible voxels or layers are seen, incredible quality for those prints which didn’t fail.

Yet the failure rate is still significant for my taste, so I need to pay close attention to room temperature, and other aspects:

The cause of the “delimination” isn’t clear yet to me, it seems the prints with proper support and elevated bottom printed better, but I need to confirm with more prints.

More photos you find at MSLA printing Triply Periodic Minimal Surfaces (TPMS).

Curing Station

As a start I assembled a simple DIY curing station with a 5m UV LED strip and placed it inside a plastic cup, with some aluminium foil at the bottom and top lid:

I only cure for 4-5mins, longer exposure changes the white resin into yellowish tint, and indicates over curing.

Keeping Resin in the Vat

After a print, the resins needs to be filtered for impurities, such as partial cured pieces not attached to the part, with a funnel and filter into a cup or bottle, and then it can be poured back into the vat ready to print again.

One can leave the resin in the vat for weeks, if you stir the resin short before you print again – stirring the resin within the vat is not ideal, as one has to avoid to scratch or FEP film; yet there is no need to pour resin back into the bottle unless one changes the resin, like the brand or color.

Drip Hook

I remixed an existing drip hook for Photon Mono to fit Photon Mono 4K, and make it easier to slide the bed on and off.


Spring Steel Build Plate

Additionally I’ve got a spring steel build plate 135x80mm with a magnetic base for EUR 10 (2022/12).

This turned out to be a good choice, the removal of the pieces is easy without additional tool.


  • the thickness of the adhesive magnet holding the plate required the optical Z endswitch to recalibrate, instead to move the sensor, I extended the light breaking piece with just a small piece of paper with a drop of glue – it was easier than 3d printing an extender for the entire sensor.
  • in my case the small handle of the plate scratches on the original vat at the last 3-4mm height, therefore the entire plate needs to be slightly misaligned (just pushing one side while fastening the build plate) so the handle doesn’t touch the vat.
    • third party Anycubic Mono 4K vat like from Mega/Kingroon have a larger space, and don’t need any fiddling around therefore
  • the spring steel is sharp, it happened several times the single-use gloves being torn/cut while handling the plate

(One of) My Use Case

After a few days I aimed for the main use case of mine: printing custom pulleys.

MSLA @ 35μm XY, 50μm Z vs FFF @ 400μm nozzle, 100μm Z

As I printed them with Anycubic Water Wash White Resin without support, the “elephant foot” comes from the first 6 layers being cured for 40s as in my case, and the UV light refracting and curing more than meant to be, but I can neglect this.

16 custom pulleys ID8 20T printed with Anycubic Photon Mono 4K in 1h 30m or 5m30s per piece

geometrical accuracy★★★★☆1)★★★☆☆
surface quality★★★★☆★★☆☆☆
mechanical sturdiness(not yet tested)★★★☆☆ (PLA)
print time per piece5m 30s2)15m
print time for 1 piece1h 30m15m
print time for 16 pieces1h 30m4h
  1. due the “elephant foot” the Z accuracy was off by 0.8mm, instead of 15.0mm it’s 14.2mm
  2. when printing 16 pieces, it took 1h 30m for printing 15mm in Z, I could have printed ~28 pulleys on 132 x 80mm build plate, bringing print time for a piece down to 3m 10s


from Anycubic Web-Site (2023/03/12)

My own experience with different resins (to be extended):

Defaults V0.0.11
Firmware V0.11
Defaults V2.0.2
Firmware V0.16
White WATER WASH RESIN (Anycubic)Clear Water Wash Resin (Resione)
Layer Thickness [μm]50505050
Exposure Time [s]32.532 .. 3
Exposure Off Time [s]2.510.50.5
Bottom Exposure [s]50304040
Bottom Layers6666
Z Lift Distance [mm]
Z Lift Speed [mm/s]
Z Retract Speed [mm/s]
UV Power [%]10010010050 .. 100
NotesDistance, Speed & Retract Speed for
– [BL] Bottom Layers
– [NL] Normal Layers
individually definable
– geometrical precise– soft with 3s exposure
– stiffer & brittle with 5s exposure
– geometrical not precise (+0.2 .. 0.8mm in XYZ)

Preliminary Review


  • good prints for the price
  • cost effective
  • power loss recovery actually works
  • lot’s of third party replacements (vat, FEP, etc)1)
  • alternatively Open Source firmware
  • nearly full reverse engineered hardware
  1. this actually is quite important: popular machine raise a secondary market for replacements: future replacement of parts even when Anycubic ends support


  • newly bought machine had outdated firmware
  • updated firmware calculates wrong total print time, this is just sloppy
  • touchscreen unreliable (wrong position) ‘print’ vs ‘delete’, use a soft pencil
  • slow prints with default settings (1mm/s Z motion), not nearly at 50mm/h height as advertised


  • slicer print settings are ignored, only settings on the machine matter
    • advantage: once sliced the .pwma can be printed with different resins and settings changed on the machine only
    • disadvantage: one has to memorize or document settings for different resins, as it not stored in the .pwma file


It’s a low-cost entry level MSLA machine, Anycubic seems to care little about the software (2023/03) as the slicer as well the firmware are Minimal Viable Product (MVP) level, but aren’t mature or reliable at all. Given they sell 500K+ machines per year at least, investing to improve in the firmware would help 500,000 users.

Small anecdote: I bought a pre-owned Mono 4K, becoming “Photon 2”, from official Anycubic store at Ebay directly – the listing said the machine likely would miss some parts – but I felt to get some more in-depth experience, and I’ve got what I asked for: the machine came dirty with resin all over, no power-supply, no build-plate, no vat, and cured resin between LCD and underlying (acryl-)glass, spent EUR 120+ for replacement parts, and 10+ hrs cleaning it to get it in working condition again. From a cost saving point of view not worth it, but experience wise it was good to get to know the machine more thoroughly.

(M)SLA Value Comparison

A numeric value summarization for features I care about:

Formula: XY Area [cm2] / Price [EUR] / (XY Resolution [μm] * 10): the bigger the XY area, the smaller the price and the smaller the resolution.

State 2023/11

Photon Mono M519μm x 24μm2)MSLA218x123x200410 EUR2.72
Photon Mono X 6Ks34μmMSLA196x122x200280 EUR2.51
Saturn 3 Ultra19μm x 24μm2)MSLA218x123x260480 EUR2.32
Photon Mono 4K d/c35μmMSLA132x80x165150 EUR2.07
EMake Galaxy 125μm / 100μm1)SLA400x200x4001,600 EUR2.00
Photon Mono X248μmMSLA196x122x200260 EUR1.91
Photon Mono 235μmMSLA143x89x165210 EUR1.73
Photon M3 Max45μmMSLA298x164x300980 EUR1.10
Formlabs 3L25μm / 100μm1)SLA335x200x3009,000 EUR0.18
Formlabs 3+25μm / 100μm1)SLA146x145x1853,500 EUR0.15
Prusa SL1S49μmMSLA127x80x1801,700 EUR0.12
  • d/c = discontinued
  1. Formlabs & EMake SLA printers use a laser beam which has 100μm in diameter, but it can be positioned 25μm exact, the latter was used to calculate the value
  2. The UV pixels are non-square, the longer side was used to calculate the value

The XY area in SLA scales not as good as with MSLA, as the laser beam takes longer the more XY area (e.g. more pieces) need to be rendered per layer – so, MSLA is recommended for aiming fast parallel printing.


Anycubic Photon Mono 4K specific:

General Photon Series MSLA:

MSLA Slicers:


3D Printing: MSLA printing Triply Periodic Minimal Surfaces (TPMS) – Gallery


  • 2023/07/25: adding 20mm/40mm TPMS photos
  • 2023/03/12: starting write-up, and published

20mm cubes of several Triply Periodic Minimal Surfaces (TPMS) as explored at Generative Parametric Infill Geometries printed with MSLA (Anycubic Photon Mono 4K) at 35 μm XY, 50 μm Z:

Most of the cubes were printed without support, the cylindrical and spherical projections required supports.


20mm and 40mm cubes of TPMS mounted on canvases: