Monthly Archives: November 2022

Misc: Formnext 2022 Review

Updates:

  • 2022/11/21: published
  • 2022/11/19: starting writeup

Introduction

Formnext 2022 was a 4 days Additive Manufacturing (AM) event in Frankfurt (Germany) November 15-18 2022, and it had ~750 exhibitors, two huge halls numbered 11 and 12 each with two floors. I attended the 4 days and it was pretty overwhelming. I try to give an overview, for myself to process what I saw, and perhaps for you who couldn’t attend.

E3D Online

E3D is an old timer among 3D printing enthusiasts, so I start with their booth:

I was surprised to get to know E3D manufactures for UltiMaker their CC printcore.

Duet3D

Duet3D is a small UK-based company, but very influential due their excellent and often praised customer support and support forum aside of their slowly expanding board selection:

I met Tony Lock, and we discussed current state of multi-axis support in Duet/RepRapFirmware, and he showed me the Open5X by Freddie Hong printing non-planar as crafted by FullControl.xyz

I briefly pitched my new tool VirtualGcodeController (vgcodectl) which sits between printing program and the device, and able to change G-code on the fly, transparently bi-directional – as I was told Duet has an alike infrastructure called Duet Software Framework (DSF) which I wasn’t aware of.

Also check this brief interview by Mihai Design:

Multec

At german-based Multec booth I saw a multi-printhead setup with a rotating seal to prevent the inactive printheads leak filament – and a precise mechanism to lift the inactive printheads (patented):

3devo

Dutch-based company providing infrastructure to mix and extrude your own filament, not just for mixing different colors, but also different materials and achieve custom material properties – the only downside is the price-tag of those desktop filament extruders starting at 10K EUR – which is too high for its functionality for prosumers, and seems to aim for R&D departments of larger companies.

Commercial Slicers

As I have been entering slicing development more seriously, and closely paid attention to possible competitors or collaborators – and interestingly, the majority responded positively when I approached them:

CreateItREAL

A small danish company, who recently patented interlocking (Z-offsetted layers) printing patterns.

I had a brief chat with Folmer Gringer Brem about industrial slicer capabilities and customer needs, and what I have researched the past year.

Adaxis

A new french company is providing non-planar 5-axis slicer with a nice GUI, and were open enough to give an actual demo and I was impressed by the responsiveness of the GUI but were tight-lipped to reveal anything about the internals – 5-axis slicer with infill patterns:

FreeD Printing

A small 2 person german company, a spin-off from the university Bochum, also coding 5-axis non-planar slicer, showing a small desktop 6-axis robot to print an overhang model, their own logo, and it has infill – which means, they actually did properly slice 5-axis G-code. They were reluctant to go into the details, as their IP represent their core asset as a company:

AiBuild

AiBuild has a huge booth, lots of advertising, has been very secretive last year as they didn’t want to demo their software without NDA to anyone – but while attending Formnext 2022 I was able to get to talk to people who purchased the software, and all of them have been giving me strange feedback: a sort of underwhelming sensation – the software is costly and not deliver what is advertised: you need to know a lot of slicing in order to use the software – there is nothing “Ai” (Artificial Intelligence) as the company name implies, at least not with their slicing software.

On their booth they had the usual non-planar printed pieces, but none of them had infill, so they all are printed in vase-mode or single wall.

One feature I saw though impressed me, it was the live quality control they implemented, having a nozzle camera and machine learning / AI to determine over- and under-extrusion – something which I would say one should have under control, but perhaps it was to illustrate the detection mechanism.

VShaper

Poland-based 5-axis printer manufacturer has progressed in hardware and software, and developed their own 5-axis slicer – the simulation shown as the actual printer prints – overall well designed.

I had a brief chat with Adam Wajda about the state of their hardware/software stack, very open and friendly exchange.

Duplex3D

Hungary-based startup with a dual delta setup printing upside and downside at the same time. They were present last year Formnext 2021 already but with an inactive printer, and this time showing the printer in action:

Beside reducing print-time the printer also is able to print pieces which otherwise are hard or impossible print when layer orientation is given and surface quality is of high priority.

UltiMaker

The newly merge Ultimaker + MakerBot = UltiMaker had no booth again, hardly any presence – the marketing / sales department seems in hybernation to skip such as event without their own booth, no hardware innovation on display, perhaps there is nothing (new) to show.

I visited the 3dimensional booth and someone showed me how to print “metal” (just steel as it turned out) with BASF metal filament on a Ultimaker S5, and having everything needed in a nice box and then send off to wash & sinter.

Snapmaker

Snapmaker announced a new machine called Snapmaker Artisan: single head operation, yet changeable heads: FDM head, CNC head, laser head – very sturdy desktop machine, using linear motors:

NematX

Bleeding edge high temperature resisting materials, and to show the applications they built a most precise FDM printer I have seen so far – Chiara Mascolo briefly showed me the machine and samples:

Nexa3D

Massive SLA and SLS machines shown:

Formlabs

The Formlabs booth was well visited, and it was hard to take photos until the last day of the expo – so just a brief video of the Form 3+ printing below:

Quantica

German-based startup printing with 7 different light curable materials at the same time, drop size / resolution at 60um with the NovoJet C-7 – quite impressive, with the ability to blend drops or let them cure side-by-side giving new possibilities of material gradients in 3D space:

They also provide a station for fluid testing & development, so you can engineer your own material to print with. Even though this was a small both it was for me from a technical point of view most innovative I have seen so far.

Nanodimension

As I was looking at resin printheads, I was approaching Global Inkjet Systems (GIS) – a subdivision of Nanodimension:

  • Fabrica 2.0: impressive 2um resolution, but as consequence 1mm height / hr print speed, SLA/DLP
  • Admaflex 300: 35-88um XY resolution, 10-200um layer height, up to 60mm/hr height print speed, resin combined with ceramic/metal printing

Inkbit

A massive industrial resin jetting 3D printer, build-volume at 500 x 250 x 200 mm printing with wax as support material. It is a closed-loop system, it prints, cures and measures the actual layers and adjusts live for the next layer – achieving 100um precision, yet only for industrial application due the cost of 1M USD per machine.

They developed their own packing algorithm in order to achieve high density packing ratio.

Breton

Italian-based “Betron Genesi” 4000 x 1900 x 1300mm build volume along with high volume extrusion (~20mm nozzle, layer height ~4-5mm based on my own photos) having excellent extrusion precision, along their real time temperature control:

Additionally is is a hybrid able to run also CNC milling on the same machine for post-processing.

Phaetus & DropEffect

Visited Phaetus expecting to just meet sales people instead I ran into Maximilian Arnold, owner of DropEffect which designs hotends under his own brand but also for chinese-based Phaetus as R&D director. I showed him photos of my early prototype of a Multi-In Mixing Hotend supposed to be printed in Aluminium and he immediately commented on my design and gave me useful input – unexpected interesting and fruitful exchange.

A brief interview with Max conducted by MihaiDesigns:

XAct Metal

This booth impressed by the samples they showed:

Namma

France-based company combining FDM and CNC together:

What you achieve with this is incredible precise plastic pieces at 20um precision, while maintaining 500 x 500 x 500mm respectively 1000 x 500 x 500mm build-volume. They are milling with a round drill bit – CNC toolpath is calculated by Autodesk’s Fusion 360 though.

Metalworm

Turkish-based company wire arc welding with 6-axis robot:

Bloom Robotics

Massive ABB 6-axis robot FDM printing on a rotating 2-axis bed . . . with shiny cyan/pink/violet lights, a bit of an overkill with the lights, but the setup was impressive:

Miscellaneous

Aftermath

It has been overwhelming expo for me, 4 days in noisy halls, constant audible and visual stimuli grown tiresome for me as I was eager to absorb all; I can say I looked at every single booth, and decided within few seconds if something caught my attention, and I knew to lookout for things I did not know or a company I did not recognize – for new companies in the arena of Additive Manufacturing. It took me a single day to roam both floors of a single hall, so at least it takes 2 days to explore two halls of the expo – and if you happen to explore a booth for more than a few mins, you end up with 3-4 days attending easily.

So, the overall impression of mine has been:

  • 3D printing / Additive Manufacturing (AM) specializes into niches more and more
  • resins printed as drops at high resolution & precision
  • paste-like materials get printed in high extrusion quality
  • metal printing showing incredible wide-variety in regards of materials
  • industrial machines are still pricey but seem to me become more affordable, instead of 10M’s they are becoming 100K – 1M while maintaining same functionality
  • multi-axis FDM with robots become more established to print large scale parts
  • in-process/live quality control and logging/documentation for FDM and powder-based processes
  • many startups still coming up with new or refined existing processes
  • gap between prosumer and affordable industrial machines is closing
  • quite open atmosphere, people are willing to share and discuss their technology, collaboration seems more important than eyeing on each as competitors

Some impressions of Frankfurt (Germany) . . .

That’s it.

3D Design: Parametric Mixing FDM Hotend with Metal Printing

Status: early prototype, metal printed model, temperature testing, no extruding yet

Updates:

  • 2023/01/09: iteration 2 testing results
  • 2022/11/22: early heating tests, no extruding yet
  • 2022/11/21: iteration 1: SLM AlSi10Mg metal printed photos added
  • 2022/11/19: published finally
  • 2022/09/10: adding photos of PLA+ prototype
  • 2022/09/02: starting writeup

This blog-post will be updated as I progress.

Introduction

I experimented with the Diamond Hotend in the past, but I was limited with the setup given – and adding another color or otherwise change the design seemed impossible, but it has changed now.

Metal 3D printing has been a niche and high priced application the past years, but in 2022 many 3D printing services support:

  • stainless steel: low heat conductivity 15W/mK
  • aluminium: good heat conductivity 210W/mK, yet low melting point 660C°
  • inconel: low heat conductivity 15W/mK
  • titanium: low heat conductivity 17W/mK

at relatively low price and all of the sudden designing a FDM mixing hotend, where multiple filaments are mixed together before exiting the nozzle – like with the Diamond Hotend – can be printed in metal, like with aluminium – so, I started to design a Parametric Mixing Hotend.

Concept

  • parametric design with 2 up to 6 filaments inputs
  • combine heatblock, heatbreak and heatsink, make it compact
  • permit ordinary nozzles (MK8/E3D V6), using M7 thread
  • orient heat cartridge vertically (like a E3D Volcano) to support up to 0.8mm nozzles
  • single 30mm fan for heatsink
  • using PC4 M10 or M4 pneumatic couplers as intakes

Pros:

  • mixing colors: 2 to 6 colors, CMY(KW), actual true color printing
  • fast switching of materials, given they have similar extrusion temperature

Cons:

  • filaments must be present in order to withstand backpressure even if not printed
  • filaments must be printed eventually, otherwise ‘bake’ in the hotend

Challenges:

  • controlling actual mixing in the chamber, e.g. creating turbulence to mix properly
    • creating turbulences may limit retraction, which is anyway not easy with mixing hotends

Gallery

The filament channels:

Mounting options, plain mounting holes 3x 20mm, or plate with 3x 40mm holes:

and adding my Parametric Part Cooler:

Gallery

Early prototype printed in cold white eSun PLA+ 0.25mm layer height (~1h 20m print time):

Adding nozzle, heat cartridge, heat thermistor, heatsink fan and pneumatic couplers PC4 M6:

and just testing my Parametric Part Cooler using 50×15 blower fan:

which very likely leads to have a some sort of thermal insulator aka silicon sock for lower part of the heat chamber and nozzle.

Metal Printing

The first attempt to order with WeNext using SLM failed, they were not able to find a way to print it without support, which was surprising as powder-based metal printing1) – the removal of support was not guaranteed, so I canceled the order.

  1. SLM powder-based printing requires support structure to counter act geometric distortion when sintering, when the piece shrinks.

The 2nd attempt with PCBWay – disclosure: they approached me a couple of weeks later to sponsor metal printing process, which I agreed on – also using SLM AlSi10Mg at first looked good at first, but then they also needed to add supports once the production step came close, and then I followed up and approved the production. The order was submitted November 5, and 14 days later the piece was at my door.

  • the print quality is excellent, the supports have been removed pretty much with little remains (between the cooling plates a few spikes remained but they have no functional influence)
  • a bit rough surface overall, more than I expected; which means, the inner holes are also rough and likely add friction to the motion of the filament

Preassembled with MK8 0.4mm nozzle, 30mm fan, heat cartridge and thermistor:

and 2x PC4-M6 threaded, with PTFE tubes:

Heating

My test rig:

  • Mellow Fly Super8 V1.2 running RepRapFirmware with two stepper motors attached driving two extruders in Bowden style
Test rig: Mellow Fly Super8 running RepRapFirmware 3.4.1, two steppers/extruders with custom mixing hotend printed in SLM AlSi10Mg (Aluminium)

Pass 1: First results

I heated to 50C°, 80C° and 100C°:

  • thermistor does poor job to measure actual temperature at the heatblock ~20C° off
  • heat conductivity to nozzle is very poor, barely heat up at all (when thermister reports 100C°) – very surprising
  • heat piles up from the heart cartridge cables
  • the fan cools barely, could be better

Pass 2: Adding thermal paste

  • adding thermal paste for the thermistor and nozzle thread
  • running M303 for 100C° and keeping it at 100C° for 10mins
  • lowest heatsink fin reaches 50C° – also connects to heatsink fan
  • nozzle looks cold (but when touching it it is hot), filament will definitely melt above
  • heat block has consistent heat distribution

Pass 3: Setting 150C°

  • heatblock is at ~120C° while thermistor reports 150C°
  • the filament pipe above the heatblock is at 100C°
  • the nozzle looks cold, but is hot at 105C° when touching with 2nd thermistor, an issue with reflective brass not properly showing proper thermal reading

Pass 4: Lowering Fan

As the lowest fin heats up significantly, as a first remedy I lowered the heatsink fan a bit:

  • lowest fin is cooler, also overall better air flow; the fins seems a bit too thick, thinner would be better
  • lower end of heat block has near set temperature, delta of just ~5C°

Conclusion Pass 1-4

  • make heatbreak section of pipes thinner
  • optionally have PTFE tubes until lower end of heatsink for smooth motion of filament
  • make fins thinner
  • lower heatsink fan by one fin

Iteration 2

After the tests, I changed the design slightly:

  • thinner pipes to lessen heat transfer to the heatsink
  • a few wings on the fins to increase heat dissepation
  • thinner fins so the air flows better

Submitted to PCBWay 2022/11/29 for manufacturing review, a day later I was informed of thin walls of the pipes near the heatbreak (<1mm) and I gave OK to manufacture.

Iteration 2 of Parametric Mixing Hotend

The thin heatbreak walls seemed to help:

  • ability to heat up to 210°C nominal, some parts reach 220°C, but nozzle is around 210°C
  • 30mm fan performs well
  • 40mm fan removes too much heat, no possible to reach 210°C anymore
  • heatbreak pipes are still too thick, too much heat flows away (hence 30mm vs 40mm fan)
  • first extrusion worked, but after 1-2min both channels are blocked, near lowest fin of the heatbreak, to clear the blockage, I removed the fan and heated to 180°C and allow entire hotend to reach ~90°C, then with 0.4mm needle and 1.8mm copper wire was able to clear the blocked section

Conclusion

Heatbreak is most critical, and has to be short and has to be a hard cut temperature gradient-wise – and 0.5mm wall thickness is still too much. So, regardless of cooling fan on the heatsink, if the heatbreak is too thick, too much heat creeps up or away – it’s not a matter of cooling capacity, but conductivity.

Todo

  • metal printed version (aluminium), done 2022/11/21
  • heating tests (on-going)
  • test prints with multiple filaments
    • 2 inputs, e.g. complementary colors (Black/White: Grey Shades, Yellow/Violet: Red Shades)
    • 3 inputs, e.g. CYM: saturated colors only
    • 5 inputs, e.g. CYMKW: full spectrum colors
  • silicon socks for all variants, as part cooler will introduce otherwise heating instabilities

References

Misc: XCR3D 3in1-S1 aka Bigtree ZSYong 3in1 (Switching/Non-Mixing) Hotend

Updates:

  • 2022/09/10: designing part cooler for its
  • 2022/08/29: starting

Introduction

The XCR3D 3in1 S1 aka Bigtree ZSYong 3in1 is a neat 3 in 1 out switching hotend (non-mixing):

XCR3D 3in1-S1 – 3in / 1out (switching, non-mixing)

Pros:

  • cost effective with EUR 20-24 (2022/09) complete with heat cartridge, thermistor, 3xPTFE tubes, 30mm fan

Cons:

  • nozzle / heatblock asymmetry: the heatblock extends right-side ~2mm
  • clumsy fan fastening between heatsink ribs
  • slightly overengineered otherwise, too much mass for the basic functionality

XCR3D 3in1-S1

BigTreeTech ZSYong 3in1

NF THC-01 3in1

Very similar, but with symmertric E3D V6 heatsink:

Clones of Clones

It seems to me, the this 3-in-1 hotend with hexagon heatsink, was cloned from NF THC-01 3in1, and likely engineered by a small company, and now brands like BigTreeTech, XCR3D and others purchase in bulk the hotend black/red anodized and their white brand stamp on the hotend.

What makes things truly confusing is that the hotends from China have terrible naming, e.g. “3in1” and “2in1” are used for switching and mixing hotends, which are quite different functionalities, and otherwise the name does not distinct designs.

Part Cooler

I adapted the Parametric Part Cooler using 50×10 blower fan for the XCR3D 3in1 S1 as well:

Download Part Cooler

As you can see on the illustration and photos, put the part cooler on the heatsink, and then 30mm heatsink fan on top. The part cooler itself requires 50x15mm blower fan.

It is a bit fiddly as there are no clear threads for the screws on the heatsink, so the first mounting is crucial to thread properly.

Marlin 2.0.x Configuration

In Configuration.h one has to update the thermistor type:

#define TEMP_SENSOR_0 5    // changed from 1 to 5

...

#define PID_FUNCTIONAL_RANGE 25   // changed from 10 to 25

recompile, upload/update firmware and then run via G-code console the autotune PID procedure:

M303

and after 3-5 mins or so, when the autotune is done, save settings in EEPROM:

M500

and one is done.

Conclusion

I really struggled to get decent quality prints first, as somehow the temperature reports were off by 40C°, and various Google searches gave the same wrong answers, the seller did not give proper detailed information about the thermistor either. Eventually at Amazon one customer gave the relevant information ATC Semitec 104GT-2/104NT-4-R025H42G and defining TEMP_SENSOR_0 5 in Marlin gave sane results.

Retraction settings are in my case 3mm at 70mm/s with apprx. 500mm long Bowden tube on my Ashtar C (CoreXY 400x400x380) and also Ashtar K #3 (300x300x360).

Ashtar K #3 with XCR3D 3in1-S1 hotend with 3 rolls of filament

I really like the switching filament solution close to the hotend, compared to other multi-material solutions where materials are switched far away from the hotend; e.g. switching material is faster, but one has to still purge one material/color by 30-50mm filament – so I tend to use the multi-material/color feature for fast switching colors for single material/color prints.

Following procedure I use when switching material:

  • heat up nozzle
  • purge 30-40mm regardless
  • retract 55mm at 70mm/s
  • switch to new material/color (e.g. “T1“)
  • push 55mm at 70mm/s forward
  • extrude/purge 30-40mm filament
  • start actual print
  • [ … ]
  • end print
  • retract 55mm at 70mm/s
  • switch to “T0
  • push 55mm at 70mm/s forward [note: not purging material/color transition]

so by default “T0” is ready to be printed. In order the print with the other materials, I have two macros with Print3r e3-t1 and e3-t2.

print3r --printer=ashtar-c-1 print cube.stl @e3-t1
print3r --printer=ashtar-c-1 print cube.stl @e3-t2

~/.config/print3r/macro/e3-t1:

prepend_gcode="G91\nT0\nG1 E20 F100\nG1 E-55 F3000\nT1\nG1 E55 F3000\nG1 E30 F100\nG90\nG92 E0\n"
end_gcode="G1 Y{$machine_depth-10} F6000\nG92 E0\nG91\nG1 E-2 F2000\nM140 S0\nM104 S0\nG1 E-55 F3000\nT0\nG1 E55 F3000\nM84\nG90\n"

and ~/.config/print3r/macro/e3-t2:

prepend_gcode="G91\nT0\nG1 E20 F100\nG1 E-55 F3000\nT2\nG1 E55 F3000\nG1 E30 F100\nG90\nG92 E0\n"
end_gcode="G1 Y{$machine_depth-10} F6000\nG92 E0\nG91\nG1 E-2 F2000\nM140 S0\nM104 S0\nG1 E-55 F3000\nT0\nG1 E55 F3000\nM84\nG90\n"

The way it is composed: start_gcode + prepend_gcode + slicing G-code + end_gcode.

Sourcing / Purchase

Declogging

As it happened to me several times, the hotend clogs up and the reason is often the filament is not hot enough, and when pulling back/retracting it forms a long pointy drag, and might break and the next cold filament jams in further down, but not enough to melt – it clogs up eventually.

First solution is to heat hotend at 240C° at least, not more than 250C° because of the PTFE – and try to push with filament on top, eventually some of the clogging might melt and free the nozzle.

Second solution is removing the lower part with heatbreak, heatblock, by opening the worm screws at the heatsink, and review the PTFE intake:

References