2022/12/22: adding Ashtar D (Classic XY) MG3 IDEX, comparing Y-XZ vs XY gantries in regards of inertia and slicing approaches thereof
2024/12/20: early idea to add tool changer as well
2024/12/16: adding more details with multiple extruders on same X gantry
2024/12/06: early ideas about single layer segmenting
2024/12/05: starting write-up
Table of Contents
Introduction
While working on theoretical side of parallel 3D printing, I used the example of multi-gantry or Multi Gantry (MG) setup where a single bed is shared in Y – here a few rough sketches using Y-XZ gantries:
Multi Gantry with same order, Common Y Rails (CYR)Multi Gantry with same order (closeup), Common Y Rails (CYR)Multi Gantry with ability to change order, Dedicated Y Rails (DYR)Multi Gantry with ability to change order (closeup), Dedicated Y Rails (DYR)
Y-XZ Gantry Approach
When having moving gantry implementing Y + XZ motion, there are several challenges, such as the Y- and the XZ motion system and making the thickness of each gantry as thin as possible to have as little “dead” or “unusable” space as it adds up and also limits the printable XY space.
Y motion system
We can share a single rail where each gantry rides hence Common Y Rails (CYR), then they can’t change the order, in that case the belt routing becomes the main issue of concern – whereas when each gantry has its own rail hence Dedicated Y Rails (DYR), and each gantry has a distinct height they can change the order (lift Z to the top and move over the lower one – hence each gantry has a different Z height, but with the filament and cabling the entanglement needs to be closely observed).
Single Rail, Multiple Gantries aka CYRDedicated Rails per Gantry aka DYR
XZ motion system
We require to have two positioning axes to integrate here, the X and Z:
two independent motion systems (X axis = 1 motor, Z axis = 1 motor)
Core XZ system also using two motors, but having XZ motion combined
Jon Schone’s (ProperPrinting) 2 Gantry System: X & Z axes with each their own motor, sharing a single Y rail
Jon’s approach is clever to use CoreXZ and position both X/Z motors near the bed, so they don’t swing higher in Z, and only have the E motors ride on the X beam, yet, his setup is a single printhead on the X-beam.
XY Gantry Approach: Less Inertia
Classic XY (non-CoreXY) where X and Y motion is separated – like the Ashtar D – the moving gantry only has a X beam, where printhead and X motor resides – whereas with CoreXY only the printhead resides on the X beam, and XY motors are stationary/non-moving. As we separate in Y, we can use this Classic XY setup to add also multiple gantries, something like this:
Ashtar D MG3 IDEX [draft: Y motion not yet separated]
Comparison
Gantry KInematics
Moving Motors per GANTRY
Moving Motors in MG3 IDEX per Gantry
independeNt AXES per Gantry
Y-XZ
n*X, Y, Z, n*E
6 (2+1+1+2)
YZ
XY
n*X, n*E
4 (2 + 2)
Y
n-amount of printheads (IDEX: n=2) per gantry
The Y-XZ gantry setup has more moving parts, especially the heavier stepper motors, whereas XY gantry, as its name indicates, has the Z kinematics in common for all gantries and therefore only X motors moving – plus printhead (E) motors for both options.
So, if we aim to reduce the inertia like heavier stepper motors, we also lose that independence in the kinematics: with Classic XY gantries they all share the same Z height.
Slicing for Multi Gantry System
As I realized earlier, it makes no sense to statically segment Y-space for each gantry (e.g. Y-size/n) although it would make coding easier, but seamless printing would be impossible – in reality, we need slightly overlapping spaces to achieve zero space seams where the gantries print for the same piece, so we naturally choose flexible non-overlapping operations.
Layer Segmenting
Obviously one of the simple optimization is when we are looking at a single layer, and segment it area-wise to n-amount of gantries. For sake of consistency, a wall is assigned to a single gantry to have a seamless wall/perimeter.
Y Segmenting Single Layer for 4 gantries & nozzles (red, green, blue & yellow)
Infill areas are Y segmented
each area (e.g. A1-A4) is the same to distribute work equally
Walls/perimeters are assigned to a single gantry
if walls intersect each other in Y, those are printed sequentially not in parallel to avoid Y collision
The layer segmenting approach makes it rather easy so all nozzles have the same Z, thereby segmenting print jobs becomes easy as well.
Mixing Multi Gantry (MG) with IMEX (IDEX & ITEX etc)
We can also mix Multi Gantry (MG) with IDEX (Dual) or ITEX (Triple), or in general Independent Multi Extruders (IMEX), something like this:
Y-XZ Multi Gantry with IDEX: Independent Dual Extruders per single XZ gantry
Layer Segmenting of Multi Gantry (4: red, green, blue, yellow) with IDEX (2) per Gantry
And like-wise segmenting layer areas in Y as before, and additionally segment in X for each printhead on Independent Multi Extruders (IMEX), in this example it’s IDEX (Dual).
As IMEX looks like scaling print parallelism further, one has to be aware of the spatial overhead for each printhead, e.g. a single printhead occupy ~40mm width in X, and similar in Y.
MG3-IDEX: Ashtar M vs Ashtar D
Early draft with more details based on Ashtar M (Y-XZ gantry), extended to MG, with Common Y Rails (CYR), with IDEX; and for comparison Ashtar D (XY gantry) with MG and IDEX:
Ashtar M MG3-MIEX2 [draft: Y motion system missing]IDEX DetailAshtar D MG3-MIEX2 [draft: Y motion system missing]IDEX Detail
Challenges
1a) When doing a Y-XZ gantry MG3-MIEX2 (3 gantry with 2 extruders each):
X: 3*2 motors = 6 motors
Y: 3 motors
Z: 3 motors
E: 3*2 = 6 motors we end up 6+3+3+6 = 18 motors to coordinate & control.
1b) for XZ gantry approach:
X: 3*2 = 6 motors
Y: 3 motors
Z: 1 motor (or more, but all synchronous)
E: 3*2 = 6 motors we end up with 6+3+1+6 = 16 motors to coordinate & control.
2) Slim design of the gantry to reduce dead-space in Y.
3) Slim printhead design to reduce dead-space in X.
4) Slicer requires to coordinate 6 printheads (e.g. T0-T5) in non-colliding and efficient way.
Solutions
Slicer
A dedicated slicer is required which segments each layer into printable areas A1 to An whereas n is the amount of gantries, and those areas might be further segmented by m-amount of printheads on the same gantry, so they share the same Y position but can have distinct X position but not switch order or collide.
As proposed above, a single printhead of a gantry is then assigned to print within the same Y-segment the walls/perimeters to have a clean wall, hence, the infills are distributed among all the printheads.
For segmenting entire sub-volume and not just layers, the Y-XZ would allow distinct Z, e.g. one gantry printing higher and another lower – the XY gantries share the same Z, therefore there only the layer segmenting is possible.
Firmware & Controller
The controller with its firmware we have a few options:
M400: wait for current moves to finish (when using T<n> with G1s together, applies to X, Y, Z, and also E)
M596 P<n> selects motion queue, prior each G0 or G1
M597: collision avoidance (at firmware level)
M598: sync up multiple motions (faster waits for the slower)
Klipper
Marlin
one controller per gantry, orchestrating between controller needed
simple setup, reliable
To keep this in mind, the Y-XZ approach allows distinct Z for each gantry, whereas the XY approach all Z of the gantries are the same.
As the operation of the gantries are overlapping, they cannot have relative position, but rather have absolute Y position (relative position used to detect collision), the same for the X position.
Adding Tool Changer (TC)
In order to support a tool changer, the printheads need to reach a common position in order to deposit and pick up tools. In case of a single Y rail (CYR) setup this seems at first sight challenging, only a dedicated tool change per gantry, at a particular a YZ position for example. The multi Y-rail setup (DYR) allows any gantry to reach a common region in YZ, and so any printhead could deposit and pickup a tool from the common toolset.
MG MIEX Gantry Style
Toolset position
Y-XZ CYR
ends of Y rail, unique Z positions per gantry
Y-XZ DYR
ends of Y rail, common or unique Z positions
XY
first & last gantry at ends of Y rail, Z fixed
XY gantry setup still can have a tool changer but only the most front gantry, and the most farthest gantry in regards of Y, the gantries in between – if more than total of 2 gantries used – cannot reach a toolset; unless the toolset itself moves close enough.
2024/12/04: completing first table on printheads & nozzles
2024/07/30: starting write up
Table of Contents
Introduction
When depositing material through a nozzle, the variables to compose a workpiece depends on the amount of nozzles and their operational spaces – let’s lay out the different methods which gives us the foundation to tackle then parallel procedures in the next part in the series.
Printheads, Nozzles & Operational Space
Printheads
Nozzles per Printhead
Nozzle Size [mm]
Layer Height [mm]
Material
Operational Space
Single nozzle FDM/FFF
1
1
0.1-1.0
0.1-0.6
Polymer (PLA, PETG, ABS)
100%
Dual nozzle FDM/FFF aka IDEX
2
1
0.1-1.0
0.1-0.6
Polymer (PLA, PETG, ABS)
2x 50%; horizontally separated
Duplex F2
2
1
0.1-1.0
0.1-0.6
Polymer (PLA, PETG, ABS)
2x 50%; vertical separated
CM3P Dual Conical
2
1
0.1-1.0
0.1-0.6
Polymer (PLA, PETG, ABS)
2x 50% of negative cone
Resin SLA (UV Laser)
1
1
0.150
0.050-0.150
Resins
100%
Resin MSLA (UV & LCD)
1
50M-100M
0.020-0.040
0.050-0.150
Resins
100%
Quantica NovoJet
1
96
0.050
Resins
100%
Stratasys J55 PolyJet
1
192*)
0.2*)
0.18
Resins
100%
Selective Laser Sintering/Melting
1+
1
0.1
0.05-0.10
Polymer or Metal Powder
100%
Stratasys J55: nozzles & nozzle size based on J850 specs, J55 details specs seem not publicized (2024/12)
Print Base
A print base is where the nozzle can extrude on. For the first layer, there is the print bed, after the first layer the workpiece or support structure can be build upon. One can alternatively use a stabilizing medium like silicon and extrude in such liquid medium which operates as bed or foundation like Rapid Liquid Printing (RLP) does:
Extruding into supporting materialExtruding into supporting material
The extruded material just has to stay where it was put, either a solid bed or a medium which prevents it to float out of position, or as traditionally printed on a print bed or base, very similar does Xolography where the solidified resin stays put as well.
Massive Parallel Nozzles Printhead
Resin printing with a printhead may have hundreds or even thousands of nozzles, yet, they share the same operational space, but due the parallel setup the print speed multiplies direct with the amount of parallel nozzles on the same printhead.
As mentioned above, we can also view Masked Stereolithography (MSLA) resin printing as a massive parallel nozzle setup, where each pixel is either an active or inactive nozzle depositing a voxel.
Anycubic Mono M7 Max MSLA Setup
Separated vs Shared Operational Space
Disclosure: I have been contracted to work on the Duplex F2 software stack (2022-2024).
Let’s take a look at the Duplex F2 printer where space is separated vertically, or the CM3P dual conical printer where the cone space is separated horizontally, or the Multi Gantry 3D printer by Proper Printing (Jon Schone). We have two printheads which never collide due their separated operational space, the firmware is simple and path planning is simple, both heads pretty much can operate independently.
When using more than two printheads it is beneficial to share the operational space, yet assume 6 or 8 printheads, each printhead needs rods to keep the printhead and position and orient the nozzle(s), so overlapping operational space requires extreme well planned tool paths avoiding any collision of the printheads.
Regular Operation Space Separation
We can segment or separate the space evenly or according the reach of the printheads, and each separated space can be printed without colliding. Yet, in reality the printheads mounts limit that operational space into slightly smaller spaces, but ideally:
nvolumes = volumetotal / volumeprinthead
If the individual printhead volumes aren’t regular, then we end up with arbitrary amount of printheads to cover a given print volume:
volumetotal = sum( volume1..n )
In reality, we require (slightly) overlapping operation to get seamless operation, so the “regular operation space separation” is only theoretically, but not practically.
Overlapping Operational Spaces
When the printheads can reach each other operational space, they become overlapping and controlling tool path generation needs to take care no collision is occurring (same place at the same time).
The Static Non-Overlapping Operation has static defined operational spaces where the operators can function – it’s quite obvious such solution is impractical, as in real life there would be space which cannot be reached, a kind of blind seam not reachable by either operator.
The Flexible Non-Overlapping Operation is flexible defined operational spaces, in the illustration above those spaces are co-dependent.
The Static Overlapping Operation is when those operational spaces are overlapping, yet, prefixed or static operational spaces.
The Flexible Overlapping Operation is flexible operational spaces, yet due the nature of the setup these operators cannot occupy the same space at the same time which would result in physical collisions.
Now, the last part of the last sentence may sound obvious to even mention, but bear in mind you can have two projectors shining light into a resin bath, and expose and solidify a 3D model, then these two lights acting as operators indeed occupy the same space at the same time as part of their function. So, the operators functioning with light can occupy the same space at the same time, whereas solid operators, such as robotic arms, cannot.
whereas parallelfactor is 1.0 if printheads can print parallel, or is less if the operational space is overlapping and preventing printheads to operate parallel thereby.
~ * ~
“Parallel 3D Printing / Additive Manufacturing” Part 2 follows later (will be linked when published)
Joshua Bird announced his 4-axis Polar CoreXB Printer December 1st 2024 on Reddit and YouTube:
Beside the hardware, he also implemented the required software and released it on github as “Radial Non-Planar Slicer” – an impressive undertake and success in one go.
4-Axis Linear Head(XZ), Rotational Head(Y)Bed(Z)
Even though I was impressed by the 4-axis RTN by ZHAW I wrote about, I abandoned the idea of 4-axis setup, as I considered it too limiting. Joshua’s approach to use a Z rotating bed, and the nozzle rotating ~180° or -90°.. +90° in Y-axis implements a polar (coordinate) printer.
He has a fixed Z-rotational center on the bed, and variable head Y-rotation in X. By keeping the Y-rotation (B) at 0° (vertical), the printer can print Z-planar cylindrical as well.
It can print XY Z-planar like a 3-axis 3D printer by mapping the XY coordinates into radial/cylindrical coordinates as well, so let’s summarize quickly what can be done:
polar coordinates, spherical slices
cylindrical coordinates, Z-planar cylindrical slices (fixed Y/B axis at 0°/vertical)
cartesian coordinates, mapping XY into radial/circular coordinates and fixed Y/B axis at 0°/vertical as well
So, this setup is quite powerful – and much better than the 4-axis RTN and also my 5-axis PAX setup, where the cabling and PTFE pipe for the filament prevent 360° Z-rotation / C-axis. Because Joshua’s has the Z/C-rotation on the bed, it’s fully continuous (or use a slip-ring to deliver power for a heated bed).
Dual Z Fixed X-Axis: Bad Idea?
Joshua’s original design is a cantilever, a single XZ beam with the Y/B rotation on the head. For a more large scale setup we require the X-rail to be attached on two Z rails, like the traditional Prusa-Mendel setup. In order to keep the -90°..+90° Y/B rotation of the head/nozzle, we need to position the rotation center a bit below the X-axis – but . . . this will prevent the nozzle to rotate Y/B to -90° or +90° as the gantry likely will crash with the already printed piece. So, it’s rather a bad idea to do so. As a result, we end up with a limited build volume, as the cantilever will tilt with further extending the X-axis.
Core XB: Combining Linear X with Rotational B (Y-Axis)
That is a very clever setup Joshua did, by having the linear X-axis combined with the rotational B-axis (Y-rotation) which he calls “Core XΘ” (Core X-Theta).
There are two motors (A & B) which control in “Core” manner the X-axis and the Y-rotation B-Axis or Θ
Non-Planar Polar Slicer
Joshua did also code a mixed non-planar slicer which combines multiple schemas as shown in the video:
Mixing spherical with free form slicing depending on the requirements of continuous printing without overhangs
That is the most tricky part, as polar (flexible tilt) and conical (fixed tilt) slicing may appear sophisticated, but it has its even more expanding challenges as Joshua mentions in his video, and obviously he developed a mixing strategy/schema slicing procedure to slice according the given requirements of printing continuous without supports – as when slicing non-planar, pieces otherwise easy to slice & print, suddenly have overhangs or are non-continuous or not connected anymore. So, he resolved it – let’s see the next weeks – will update this blog-post accordingly.
The S^3 DeformFDM Slicer from Manchester Uni (Tianyu Zhang, Tao Liu, Charlie C.L. Wang) has provided a solution to combine Support Free (SF), Strength Reinforcement (SR) and Surface Quality (SQ) under one umbrella of consideration and optimize all three requirements using quaterions per sample. I tried to adapt that solution but struggled to even build the solution from the sources back in 2022.
Impressive Step Forward
Joshua Bird has “single-handedly pushing the 3DP community forward.” according a YT-comment, and I whole-heartly agree, not only did he thought out of the box with the Core XB setup, but resolved multiple hardware and software challenges – impressive.
References
Polar Core XB 3D Printer (original YouTube video aka “I Built a 4 Axis 3D Printer Unlike Anything You’ve Seen”)
Formnext 2024 in Frankfurt/Main (Germany)Formnext 2024: Hammer ManFormnext 2024
Once again in fall (November 19-22, 2024) Formnext expo opened its doors, and I attended for 2 1/2 days – here my brief write-up and reflection of my experience.
Formlabs
Formlabs made an interesting move: it abandoned the SLA (laser-based) to MSLA (UV light & LCD masking) resin printing with their Form 4 series (Form 4 & Form 4L), so I briefly visited their booth:
FormlabsFormlabs: Form 4Formlabs: Form 4Formlabs: Form 4Formlabs: Form 4Formlabs: Form 4Formlabs: Form 4L
I highly recommend the taking apart of the Form 4 by Shane Wighton / Stuff Made Here to get to know all the engineering work which went into the new series.
The company behind the commercialization of the VORON series with their SOVOL printers, SOVOL 08 or SV08, a Core XY 350x350x450mm build volume, priced at 550 EUR.
So far only Genera‘s G3 does something similar where washing & curing is done in the same case/apparatus.
Prusa Research
Prusa Research announced at the Formnext their new Prusa Core One, a Core XY with 250x220x270mm build volume, nozzle temp. max 300°C, chamber temp. max 55°C, priced at EUR 1,350, with the ability to uprade from MK4S, available later in 2025.
Prusa ResearchPrusa ResearchPrusa Research: Prusa Pro Print FarmPrusa Research: Silver / White Iron ManPrusa Core OnePrusa Core OnePrusa Core One: DisplayPrusa Core One: Side with spool, nicely donePrusa Core One: BackPrusa Pro SLXPrusa Pro SLXPrusa Pro SLX
One may argue, Prusa reached a state of commercial success, that it can’t afford to support low-cost chinese replicas of their invention, exactly as it happened to Makerbot and Ultimaker – and both stopped innovate, and recently merged – let’s see if Prusa will thrive in hardware innovation the coming years or lay back as well.
Open Source Software seems more tolerable to commercial pressure: Prusa Slicer still actively developed and forked many times, and so the Cura Slicer by UltiMaker; both slicers enable countless university labs and commercial engineering offices to develop new hardware and having an Open Source implementation of reliable slicers with a ton of detail knowledge embedded when one studies the source code.
Rather unknown brand to me caught my attention the past year due to high praise from various YouTube reviewers: the older GKTwo (228x128x245mm @30um) ~670 EUR and the new GK3 Ultra (300x160x300mm @20x26um) ~1,200 EUR.
integrated heating system at 35°C
resin feeding system & resin weight measuring
built-in air filter
Industrial-level features while maintaining consumer pricing.
The booth featured Pengji (LCD maker) and Apex Maker (MSLA printers) together, so I assumed they are the same business with different brands with LCD making as core business – a representative at the booth confirmed my guess – so aside making UV LCDs they started to produce their own series of MSLA 3D printers:
Plus their own branded resins, curing and washing stations, see more at Apex-Maker.com
Elegoo
This year Elegoo released Mars 5 Ultra and the Saturn 4 Ultra which have tilting vat alike the Prusa SL1S which decreases layer print time (curing + detaching from film) down to apprx. 5 secs; so I was eyeing to get a Saturn 4 Ultra.
Thursday morning I revisited the booth and asked about whether Saturn 4 Ultra would permit to put a magnet flex plate on it – which would change the Z offset for homing, and two representatives explained to me it would be a bad idea as the home aka zero Z-position would fail, and one would require the change the “G-code” in the firmware (which is closed-source) . . . in other words, the Z offset or home position is somehow hard coded and doesn’t use pressure sensor to calibrate home (this Reddit thread shows Chitubox Slicer allows to alter the homing G-code, LycheeSlicer doesn’t have this option) – the usual rabbit hole.
My resin printing farm is composed by Anycubic printers (Mono 4K, X2 and 6Ks), mainly due the diverse third party market for replacement and add-ons, so I was checking out their new Photon Mono M7 Max (298x164x300mm @46um) priced at EUR 900 (2024/11).
I was hoping Anycubic would also implementing tilting vat to decrease the print time and allow more delicate prints due more gentle / gradual detaching from the film with the tilting motion – so far not yet.
This basic looking booth I consider a gem among a few others at Formnext 2024, a sample of massive piece which was extruded with aluminium below the melting point using Additive Friction Stir Deposition (AFSD) procedure and yet creating a fully solid piece where layers fully bond – their main photo (1st photo below) or illustration at the booth was deceptive small at first sight, but after looking twice, I realized the entire machine “Fooke AM50” is over ~6m long with a huge build volume of 6 x 3.5 x 1.5m, and aluminium, magnesium, copper, steel and titanium as possible materials, with build rates up to 15kg/h – and all extruded in normal room atmosphere and temperature.
Following video gives an impression of AFSD & FSW based extrusion by MELD (unfortunately the audio is quite silent in most parts):
grumpy, because of the patent collection which caused the 20 year delay for others to be able to adapt major extrusion technologies, once they expired the “3D printing era” actually started with affordable 3d printers (MakerBot, Ultimaker, Prusa, and all the chinese replicates) and many prosumer derivates
grandfather, because it’s truly the beginning of extrusion-based 3D printing / additive manufacturing
The cylindrical shape of a 3D printer caught my attention, and on the 2nd sight I saw it was a Positron-like setup of printing upside down, the Kokoni Sota printer:
I briefly spoke with Tianrun Chen and he explained when printing upside down, less support material required, and therefore developed their own support generation method which reduces material by 20-50%.
210x200x230mm build volume
up to 300°C nozzle temperature
optional multi material systems (also in cyndrical case)
National Taiwan University of Science & Technology (NTUST)
The little booth, and the walls where full of large scale posters with a lot of information, so I stopped and began to absorb the information – in particular the mention of TPMS caught my attention.
32″ LCD Resin Printer50″ LCD Resin PrinterResin 3D printed, heat activated foaming 2x in XYZ
So, one of their invention is a resin which when it is baked at 120°C it increases in size XYZ 2x – therefore in volume 8x – which they named “Foaming Resin Printing“, the sample prints like the bike helmet or even the small TPMS Schwarz P cube was incredible light compared to its size.
Another invention is printing TPMS like Schwarz P and then fill the partial closed P cells with a foaming agent, they call this process “Multi-Material Additive Manufacturing using Hybrid 3D Printing and Filling Process” (see non-free paper) – in case of the Schwarz P TPMS the cells are interconnected and spherical, so the agent flows into all captivities quickly as “Liquid Filled Closed Cell Lattice Structures” – and reduces print time while increase stiffness / strength – kind of combining Additive Manufacturing with Mold Injection method.
3D printing closed cells with injection of secondary material
Another achievement is their 32″ (697x392x500mm build volume) and 50″ (1,150x600x500mm build volume) large LCD/MSLA resin printers, with new film coating of better release of the cured layers, although we couldn’t get into the deep details of it. See this non-free paper and this paper for details about the 32″ resin printer.
LCD 32″ 3D PrinterLCD 50″ 3D Printer32″ LCD type vat photopolymerization 3D printing system
I could easily spent an hour to explore their different projects and the benefits of those 3 distinct inventions alone. See more at NTUST.edu.tw and its High Speed Printing research center, in particular follow Mayur Prajapati.
TUM (Technical University of Munich)
The TUM had a very prominent and large booth with many departments and many samples shown:
What caught my attention was the “Infinity Node” made from ~1mm gravel, it was printed using SLS-like printing: Particle-Bed 3D Printing by Selective Cement Paste Intrusion (SPI), using concrete as a binder to connect the small gravel together. The “Force-flow Optimized Node” (brown triangular truss shape) was done using Particle-Bed 3D printing by Selective Cement Activation (SCA).
The other samples were “Molten Metal Jetting” (Copper), “Functional Graded Material” using Plasma Directed Energy Deposition with Powder Feedstock, and “Laser Cladded TUM Logo” using Laser Metal Deposition (316L + Construction Steel).
Quantica caught my attention 2-3 years ago, also at the Formnext, as I saw the modular fully voxel-exact jetting of material. Their core business was their printhead “NovoJetTM” able to print high viscous materials, something other jetting printheads would not able to do.
This year I talked to Sven, and he explained to me that they broaden their application areas like exact glue jetting and other high viscous materials, as some industries saw their printheads as high precision material deposition, outside of the “3D printing / Additive Manufacturing” use cases – quite interesting how their core expertise found other applications.
Quantica Print Engine: circular motion of material kept under pressureNovoJet Printhead: 96 nozzles, 50um diameter each, 8kHz max frequency
Again I asked for some 3D printed samples, and again I was denied any like the past 2 years (!!) – they said they don’t have any (or very few) but just for internal use; my main interest is to observe the actual blend or non-blend and then 3D dithering of materials and colors on drop level in order to explore new applications.
An interesting approach, new to me, is Xolography, spatial printing in a resin – first a light sheet is established in the Z plane of 50um thickness, and then XY image is projected into the volume, different color/wavelength for each, and where the Z plane and the XY image light meet, there the photopolymerization takes place; it only works with highly transparent resins, more precisely dual-color photoinitiator (DCPIs), as otherwise the Z plane won’t reach all XY 2D image.
Xolography: UV light Z plane intersecting with XY plane with visible light
first wavelength (375 or 405 nm, UV light) activates the dormant initiator by triggering a spiropyran photoswitch (Z plane)
second visible wavelength (450-700 nm, visible light) excites the benzophenone component to initiate polymerization (XY plane)
So far they reached 50x89mm XY size, yet any size in Z including continuous Z printing.
They claim “no layer lines”, and told me they project a “video”, yet, a video has also n-amount of images e.g. a certain frame rate. What they rather mean is a continuous Z motion while they project their Z sliced XY images, and because the Z motion is continuous, the “layers” rather blend together and get smoothed out. They also don’t need any support structures, as the cured/solidified structure stays in-place and doesn’t sink.
Their requirement of highly transparent resin they derive one of their main use cases: 3D printed optics, and isotropic properties (angle independent strength, no deliminations), other resins they developed are bio-compatible and even soft and gel-like – quite an impressive achievement.
Currently they have two machines available:
Xube2: 10x18mm (@5um feature resolution) up to 50x89mm (@25um feature resolution) x80mm, apprx. 6mm/min in Z, feature size 5-25um as mentioned, although 50um lightsheet width/thickness, so the “feature size” more applies to XY than Z
Xell: 10x17x10mm build volume, @10um feature size
This process has been new to me as mentioned, but while researching I realized it has been around since 2020 or so, when this paper was published.
They showed a bio-attributed Cellulose Nano Fiber (CNF) made from cotton fibres, and then reinforced polyamide PA66 into a filament named CNF/ECONYL® Polymer with extended heat resistance, strength (performing better than carbon fiber), smoothness and formability – actual details of measurements are missing to backup those claims – according their announcement the material becomes available in Q3 2025.
While their booth has been very small and unassuming, the company has nearly 50,000 employees world-wide.
As far I saw they are one of few which makes resin printers which print, wash and cure in the same machine (Genera G3), where as their G1+F1 and G2+F2 they call “glove free process with shuttle technology and automated post-processing”, where the build plate is carried over in an encasing “glove free” to wash and cure station (F1 respectively F2).
Genera G1 + F1: 134 x 76 x 140mm build volume @70um pixel resolution
Genera G2 + F2: same as G1 plus automatic platform change for queued printing
153-384 x 87-216 x 320mm build volume (@40, 70 or 100um pixel resolution)
Genera G3: same as G2 but has F2 integrated, print, wash & cure in one machine
268-384 x 153-216 x 320mm build volume (@70, 100um pixel resolution)
Genera G3 (3D Model): (left-to-right) resin vat, washing vat, and curing vat
Printing metal poses the biggest challenge in my eyes as you have to put immense amount of energy to deform metal, while maintain or desire high degree of precision. So Meltio focuses on Directed Energy Deposition (DED) and Wire-Laser Metal Deposition (W-LMD): stainless steel, carbon steel, titanium alloys, nickel alloys, copper and aluminium:
Their sample prints are massive, and quite rough compared (0.8-1.2mm wire diameter) to Selective Laser Melting (SLM, powder-based) models where we get 50um feature size.
Their “Engine Blue Integration Kit” integrates into existing CNC machines making it hybrid operation and achieve traditional CNC tolerances and feature size – one of the many examples where Additive & Subtractive Manufacturing are put together with their respective strengths.
Fraunhofer is a prominent research institute in Germany, with multiple booths displaying cutting edge AM methods – I didn’t have the time to dig deeper into their samples, somehow nothing stood out prominently, or it was vaguely explained at first sight unlike at other booths.
Whenever I pass by their booth, the only thing I think is “car-sized 3D printers costing millions of EUR/USD”, it’s a different use-case from where I operate – as simple as that, and yet, still impressive what they achieved.
Lasertec 65 DED Hybrid: DED with CNC capability, with just 735x650x560mm build volume
Btw, its name comes from multiple mergers: DMG (Deckel, Maho, Gildemeister) and Japan’s Mori Seiki – a blend of german and japanese workmanship.
A few years back in 2017 they released their Mosaic Palette, splicing (cutting and melding together) filaments ahead for a single filament yet achieving multi-color with a single nozzle without material waste. Meanwhile they massively scaled up their expertise and developed their own printers called Mosaic Element and print farm called Mosaic Array – and I admired the overall case design in simplicity how the filament cartridges are attached.
Element HT2 specs:
nozzle up to 500°C
build plate up to 120°C
build chamber up to 80°C
350x350x350mm build volume
up to 8 materials via filament cartridges
price starting at EUR 9,500
Their print farm is built on stacked printers, and a robot arm removing the built-plate with the printed piece and stack it below and refill the printers with empty build plates again.
While roaming in the halls, I recognized a few YouTubers like Ross Graham (FauxHammer), Jon Schone (Proper Printing) and also Joel Telling (3D Printing Nerd):
Here his marathon live-stream at Formnext 2024:
Among others were also Xolo with the Xolography light printers, Spherene with Daniel Bachmann, Josef Prusa showing the Prusa Core One, and Stratasys representative featuring SAF H350 able to process used powder with High-Energy Absorption Fluid (HAF) with Selective Absorption Fusion (SAF).
Tony Lock (Duet) & Jon Schone (Proper Printing)
As I was visiting the booth of OST (Eastern Switzerland University of Applied Sciences) & Spherene I met Jon Schone (Proper Printing) and Tony Lock (Duet3D) and we had a brief talk on multi-axis firmware & slicing and parallel printing as Jon showed in his video with a multi-gantry setup – I’m currently composing/writing on a blog-post about parallel/concurrent printing with multiple nozzles so I was keen to briefly exchange thoughts on this topic.
Tony Lock (Duet3D) & Jon Schone (Proper Printing) – Formnext 2024
Reflection
Formnext is an overwhelming expo on all things on Additive Manufacturing, and this year less people and less exhibitors than last year. Also a few startups with big booths last year either had a small one (nTop, Inkbit, etc) or were no longer present. A couple of newcomers and startups, and some companies I have been following pushing their innovation further and exploring new applications, like Quantica.
I only stayed for 2 1/2 days (Tue-Thu) instead the full 4 days, as from last year I knew I wouldn’t be able to absorb more things with more time, there was only so much to take in. For me it was worth it, to reconnect with companies and individuals I know only online and via video calls.
The “3D Printing Hype” has peaked, the stock prices (state 2024/11/22) of Stratasys (8% or -92% of max), 3D Systems (8% or -92% of max), Desktop Metal (1.6% or -98.4% of max) or Nano Dimension (15% or -75% of max) have shown how much air and speculation was there, and now the sobering realism and use case are established. The same time MakerBot & Ultimaker merged, two exhausted 3D printer manufacturer without hardware innovation in the past years – yet Prusa, Creality, Elegoo, Anycubic still thrive on the pro- and consumer level with both FDM/FFF and MSLA resin printers, and BambuLab so successful that it caught Stratasys’s attention to sue them about patent infringements.
It’s clear to me, that Additive Manufacturing (AM) has its unique use-cases, whereas injection molds still dominate mass production due the high volume capacities and cost effective production. Additive Manufacturing may be a bland term (I like “3d printing” better), but there are still many possibilities to be explored, as Xolo or diverse university booths have shown – any kind of granular or liquid material is melted, extruded, jetted, cured or bound with an agent.
Hammer Man in Frankfurt/Main (Germany) – Symbol of a Maker
At Formnext 2023 I spent some unexpected time to discover a new class of procedural structure called “Spherene” (“sphere” + “graphene”), it’s a name as introduced by a company with the same name.
It’s main feature is isotropic (“all directions”) distribution of forces. Their service provides the creation of this structure based on:
density (ratio of material vs empty space), hence their term of Adaptive Density Minimal Surface (ADMS)
form
wall thickness
where all of them are freely definable in 3D space contained within an overall boundary. Their service “renders” a mesh which complies with such, like defining at some point a lower or higher density, and transits in 3D space from one to another.
Spherene Metamaterial in Simulation-Based DFAM: CDFAM NYC 2024 (Video Presentation)
Patent
My immediate impulse was to code the Spherene aside of the existing TPMS’s, but I realized their business core is the service of creating meshes based on their procedure as described in a patent:
at its core it describes 6 steps (abbreviations added for clarity)
creating envelope
creating density field
adaptive Voronoi tesselation (AVT),
1st skeleton graph (SG) associated to AVT (SG-AVT1)
generated from the edges of the Voronoi cells
2nd skeleton graph associated to SG-AVT1 (SG-AVT2)
generated using Delaunay tetrahedralization
minimal surface from SG-AVT1 and SG-AVT2, using equidistant from both skeleton graphs, with minimal wall thickness requirements
Abstract: A method of additively manufacturing a minimal surface structure of a three-dimensional article includes a computer executing the steps of recording, in the computer,
an envelope of the three-dimensional article; generating a density field across a volume enclosed by the envelope with densities of the density field corresponding to local requirement values of at least one physical parameter at respective positions of the three-dimensional article;
generating an adaptive Voronoi tessellation of the volume using the density field;
generating a first skeleton graph associated with the adaptive Voronoi tessellation;
generating a second skeleton graph associated with the first skeleton graph; and
generating a digital minimal surface model from the first and second skeleton graphs.
The method may further include a 3D printer additively manufacturing the minimal surface structure according to the digital minimal surface model.
I think if Spherene is truly as significant for Additive Manufacturing, and an essential invention, it has to move beyond the grip of a single company and its patents – time will tell.
Samples
Daniel Bachmann from Spherene Inc. kindly shared with me a few samples, 20x20x20mm cubes, and 20mm diameter spheres with Spherene infills, illustrating their properties:
Spherene 20mm, 15mm and 10mm sampleSpherene 40mm in white & grey resin (top row) and white, grey and black PLA/PLA+Spherene resin samplesSpherene resin samplesSpherene resin samples
A few support structures were required for the spherical samples, the cubic samples did not require such:
Lychee Slicer: spherical spherenes required support structure due overhangs
Additionally I printed a few cubic samples with FDM on my CoreXY Ashtar C without supports at 40x40x40mm scale.
Subtractive Manufacturing & Molding Usage
The structure cannot very well machined with subtractive manufacturing processes – or only if the piece is sub-divided so all indentations can be milled, and sequentially fused or welded again.
Another approach comes to my mind is to form dedicated bricks, e.g. for large scale application like a building, and have a limited kinds of bricks depending on their position and use case, and have molds to form those limited kinds in larger quantities.
In order to produce a mold one would inverse the original model, the negative volume, that would be produced using additive manufacturing and then produce lost-form casting molds, or highly simplify the form so one can remove the positive without destroying the mold.
Mathematician August Ferdinand Möbius described in his paper 1858 a shape, which later became known as “Moebius Strip”: a surface with only one side or surface and one edge:
In the physical one can take a strip and twist it once and tape both ends – when creating a 3D representation, one rotates a strip by 180° to a closing circle.
Examples
Original Moebius StripMoebius Strip with 2 stripsMoebius Strip with 3 stripsMoebius Strip with spokesMoebius Strip with 2 strips & spokesMoebius Strip with 3 stripts & spokes
3D Prints
I printed some of the models on MSLA resin printers with plenty of supports, one more flat and another series more vertical oriented which required more support structure and harder to remove.
Moebius Strip Meditation: multiple turns: 1, 2, 3, 4, 5, 12Moebius Strip Meditation: multiple stripsMoebius Strip Meditation: single turn, double turnMoebius Strip Meditation: single turn, single turn with multiple strips, both with spokes
2024/01/20: adding more examples and mounting tool/ruler
2024/01/15: starting write-up
Table of Contents
Introduction
Since a while I was wondering how to create large(r) scale 3D prints like 1m / 1000mm or more, and I thought to use wood planks as slices and make “parametric wall” like sculptures. In order to get an idea of the procedure, I started with “parametric canvas” or Slices on Canvas.
Models
I used OpenSCAD to put together a few examples with 200×150 in size, and settled for 40 slices, which are then scaled up for 400x300mm canvas, the actual size is 340x240mm giving on each side 30mm margin to the edge of the canvas.
In order to test the concept, I used 3D printed slices printed with cold-white PLA+ in order to get a strong contrasts to the black canvas:
First 3D printed slice (240mm wide, 2.5mm thick) of “Sinus Mountain Range”
Each slice is 240mm wide, and 2.5mm thick and various height depending on the model.
After printing 40 slices finished, I mounted them on the canvas:
Mounting slices on canvas with a mounting tool / ruler at bottom & top for exact spacing
As shown on the photo, I used a mounting tool / rulers, also 3D printed, which helped me to keep the slices well aligned and spaced to each other – then glued each slice on the canvas.
40 slices with 240mm width and 2.5mm thickness takes about 20hrs to print (4 slices ~ 2hrs print time) and ~520g of filament like for the Sinus themed sculptures.
Raw slice bundles: Smooth Sinus Meadow, Quarter Drop, Drop each bundle apprx. 520g PLA+
With 2.5mm thickness x 40 and 340mm canvas width, it’s about ~25% or 1/4 of actual volume of the model, and the rest is empty space in between.
Sinus Mountain Range
Sinus Mountain Range on canvasSinus Mountain Range on canvasSinus Mountain Range on canvasSinus Mountain Range on canvas
Cubes
Cubic landscape on canvasCubic landscape on canvasCubic landscape on canvasCubic landscape on canvas
Spheres
Smooth Sinus Meadow
Various Examples
Quarter Drop (#6)Drop (#7)Fast Drop (#8)
Conclusion
It’s relatively easy to create a Slices on Canvas (parametric canvas) but it takes its time to print and assemble – due the thin slices the sculpture changes its appearance drastically depending on viewing angle, and so is an eye catcher.
It certainly is a viable approach for larger scale sculptures, the saving in material is compensated with additional manual work like aligning and fastening the slices.
References
LabSlicer: used to slice the model into SVG slices (PrusaSlicer also supports this functionality)
Prynt3r: for printing the individual SVG slices directly
2024/01/22: published without much reflection & conclusion as research is ongoing
2023/12/02: adding more examples and refining details
2023/10/22: start writeup
Table of Contents
Introduction
While studying continuous fiber 3D printing and its main nature is to find ways to lay fiber without interruption. In order to refresh my memory I revisited the Lissajous forms, which until recently only knew in their 2D form, the swirling strings or lines – and now extending it into 3D as well.
The main idea is to realize how a line, string or fiber can be used to fill non-planar and circumvent a 3D structure and how angular shifting in Lissajous context affects such form.
3D Lissajous
angle: 0 .. 2pi or 0 .. 360°
p, n, m: 0 .. 1000, the amount of loops
phi0, phi1, phi2: the angular offsets 0 … 2pi or 0 .. 360°
X = sin(angle*p+phi0)*r
Y = sin(angle*n+phi1)*r
Z = sin(angle*m+phi2)*r
I did a lot of experimenting – I could post hundreds of forms – but let me focus on one a bit closer, which got my attention:
While playing with 3D Lissajous, I thought to adapt the cyclic nature, but apply it to a circle laying in the XY plane and then rotate in X axis, and Y axis as well, and optionally cyclic translation as well:
d: diameter
angle: 0 .. 2pi or 0 .. 360°
p: amount of loops as in X=sin(angle*p)*d/2, Y=cos(angle*p)*d/2
q: amount of X rotations: rotateX(angle*q)
r: amount of Y rotations: rotateY(angle*r)
Spherical Lissajous 12.23 with spreading struts
The model was printed with MSLA white resin at XYZ 50um resolution with 120mm diameter, with a few support structures near the bottom:
Spherical Lissajous 12.23 with spreading struts MSLA printed at 120mm diameterSpherical Lissajous 12.23 with spreading strutsSpherical Lissajous 12.23 with spreading struts closeup 1Spherical Lissajous 12.23 with spreading struts closeup 2Spherical Lissajous 12.23 with spreading struts closeup 3Various spherical Lissajous
Spherical Lissajous with Translations
Using the Spherical Lissajous and extend it slightly:
Another year, another November in Frankfurt (Germany) and Formnext – this is the main event of the year professionally for me. As I reside in Switzerland the travel is fairly easy and short and the 770 exhibitors in two halls (11 & 12) with two floors each is so overwhelming that even 4 days attending is not sufficient.
Day 1 (Tue, Nov 7): I spent an entire day to explore hall 12.1 alone, which turns out a good choice as it was a dense populated hall with many smaller companies
Day 2 (Wed, Nov 8): visiting with a client half of the day to review some of their possible competition, and then explore 12.0
Day 3 (Thu, Nov 9): some schedules meetings and then explore 11.0 and 11.1
Day 4 (Fri, Nov 10): revisiting 12.1 and 11.1 briefly, visiting with another client some selected booths to check products on display
I surely missed a few booths in 11.1 and 12.1 still; whereas 12.0 and 11.0 were more large scale industrial AM solutions, mixed with university and regional focused booths which I didn’t have time to explore in detail.
Personal Selection
I feature some companies according my personal professional interests:
Spherene (Math)
I made contact with Spherene before via LinkedIn but I realized I missed the point of what Spherene actually “invented”, at their booth Daniel Bachmann took the time to show me the features of their new class of minimal surface model and it was challenging for me to follow him despite of my own experience with Triply Periodic Minimal Surfaces (TPMS) – after apprx. 20 mins I realized the scope and some of their depth of their “invention”.
Spherene: sphere sample with variable porousitySpherene: resin printed rabbit with spherene infillSpherene: FFF/FDM printed bone replace with spherene infillSpherene: print samples (MSLA, FFF/FDM, SLM)
In essence, the sphere is used as a base form, and density, wall thickness and other features are processed in a localized manner, filling the space. The main result doing is optimizing a form to distribute inner/outer forces, e.g. the ends of the spheres are perpendicular to the surface providing ideal way to distribute them into a network of thin walled interconnected spheres providing isotropic (“all directions”) property.
The samples on display were printed with MSLA, SLA, FFF/FDM or SLM were indeed very strong in relation to the printed volume, e.g. the hallow rabbit printed with resin barely gave in when pushing on the thin outer perimeter – impressive.
Their approach is available as cloud-based GUI or as Grasshopper/Rhino plugin. The actual details of their procedure isn’t easily found but a patent (WO2020229692A1) by CEO Christian Waldvogel gives some idea.
Genera (DLP Resin)
There are many MSLA/SLA/DLP printer manufacturers, yet, I wasn’t aware of Genera and I was shown their system, an integrated workflow:
all resin vatshave a lid (only applies for G1/F1 combo but not their bigger machines), which are opened only within the machine
the finished prints (still on the plate) are moved in a box into the washing machine (without any person touching resin or the resin coated prints)
once automatically cleaned and post-cured, the prints are removed from the build plate manually
In essence one does not interact with resin directly, it’s all contained within the workflow – which I like a lot. They also provide wide selection of resins: hard, soft, rubbery, opaque, transparent/clear.
My idea has been to adapt some of their approach to make my own resin printing with Photon series (4K, X2 and X 6Ks); right now I also have multiple vats, and flex-plate, but moving the printed parts and washing them are still messy.
Quantica (Resin Jetting)
Last year I already visited the booth of Quantica, and so this year again. I asked earlier for printed samples, but they declined, and again this time . . . it is bizarre to see a machine actually able to print, and they don’t hand out samples, but I was told by January 2024 I might get some. This tells me a few things, the printed pieces are very sparse or not yet at the quality they want others to experience – some samples were on display, but sealed behind a glass box unable to have in my hand. So I guess now, they are expecting or already have better and more reliable printing results where the printed pieces match other similar printing processes.
QuanticaQuantica: NovoJet OpenQuantica: multi material samplesQuantica: multi material samplesQuantica: multi material samplesQuantica: multi material samples
I follow their development closely since ~2 years as I consider it very innovative to print with 7 different resin-based materials at the same time and able to fine-tune material properties on the voxel-level.
Duet3D (Open Source Hardware & Community Building)
UK-based Duet3D with its Duet boards and RepRapFirmware (RRF) is, as I wrote before, a beacon within the Open Source Hardware community – it isn’t just an example for other companies, and but also a great synergy provider, aiming to bring different individuals, groups and companies together.
Duet3D: with David’s backDuet3D: Voron 0 with Brandon Build’s variant of Open5X Duet3D 5-axis Open5X with tool changerThe many companies using Duet boardsDuet3D booth: Josef Prusa & Tony Lock – legends of 3D printing community
Brandon Builds’ Open 5X version was featured on a Voron 0, and a second machine also 5-axis setup with a tool changer.
Rapid Liquid Printing / RLP (Flexible Structures)
While roaming around a small booth of RLP caught also my attention, where a video was featured of a nozzle moving in a bed filled with silicon printing rubber, and other flexible material:
Rapid Liquid Print (RLP)RLP: multi color samplesRLP: white “finger” sampleRLP: area with flexible “fingers” and color gradientRLP: Flexible seat print with inflatable cushions
Reinforce 3D (Enhancement)
Another truly innovative approach combining and enhancing existing additive manufacturing processes was shown by Reinforce 3D:
using existing AM methods such as SLM, SLA, MSLA and even FFF/FDM to make models with thin walled tunnels and then
filling or rather pushing them with strains of carbon fibres along with resin into the tunnels
and thereby reinforcing free forms by keeping the result lightweight but incredible strong due the embedded carbon fibres
Reinforce 3D boothReinforce 3D: SLM and resin (MSLA) printed pieces carbon fiber reinforcedReinforce 3D: FDM printed and carbon fiber reinforcedReinforce 3D: FDM printed and carbon fiber reinforced
A very small but significant detail is, that you can print multiple parts on a smaller printer, but once you start to insert the bundles of carbon fiber those segments of pieces get combined in a strong assembly, as the aluminium skeleton shown above.
INo Trident – inductive hotend by Plasmics: fast heatup and cooldown / 3s from 20C to 220C, 10s from 220C to 150C
At the booth of Plasmics I looked at the inductive hotend and saw the heating up in a few seconds from 20C to 220C and cool-off in a small demo first hand.
The hot part of the nozzle looks like a needle, with little thermal mass, hence the fast heat and cooling-off time, and then surrounded by ceramics with the inductive coil on it.
The hotend incl. the controller board priced at EUR 400 is high for DIY enthusiasts but low for an industrial setup.
And UltiMaker (after Ultimaker & MakerBot merger) wasn’t present again; the consensus has been that BambuLab‘s printers have taken the higher quality consumer FFF/FDM printers market segment, and the air getting thinner for UltiMaker – at the same time they are doing a great service with the Open Source Cura slicer.
Random Impressions
Metafold: samplesStratasys: samplesPhotocentricPhotocentric: samplesPhotocentric: samplesPhotocentric: large scale statueHP: samplesPrusa ResearchPrusa Research Pro seriesSnapmakerSnapmaker with CNC drillSnapmakerSnapmaker: IDEXFormlabsAnisoprintAnisoprintAnisoprintAnisoprintE3DE3D: non-planar / belt printer nozzlesApexMakerApexMaker & PangJi resin printer LCDsSintratec: SLS printersSintratecSintratecNexa3D: SLA & SLS machinesNexa3DAiBuild: multi-axis slicingElegoo: printers, filaments, resinsFormFuturaBambu LabBambu LabDyze Design: water cooled large hotends
