How to solve a stalling Z arm on a LUTUM® with touch screen.

Adjust Z speed setting of your printer

The first models of LUTUM 5 , 5M and 4.6 have shipped! They are equiped with a brand new brain compared to the previous models and we are still adjusting and finetuning behaviour of our machines for optimal performance.
The past few months we noticed that the Up and Down movement of the X arm along the Z direction stalls in some cases. After investigating mechanical and electronic parts it appears most of the stalling can be solved by lubricating the Z axis more often than previously advised.
Adjusting the motion setting of the various macros and and speed limitation settings underlying the Z-movements gives a reliable permanent solution, however, frequent inspection of the Z-spindle lubrication condition is still recommended!

It is easy to adjust

The good news is that it is easy to adjust and at the same time learn a bit about the workings of the hardware-software symbiosis of your machine.

Below are the various steps explained to alter settings on your machine.
All steps are done through the browser interface of the printer. If you have to log on to your LUTUM via the printer acces point you might need to open this website on a different device so you can follow the steps while logged on to your machine.

First open your web browser and log on to your printer, then locate the system folder through the LUTUM UI.

Logic of the LUTUM machine instructions

In short, the printers hold a set of hard coded instuctions that define the movements of the machine.
These instructions can not be changed.
To define the exact behaviour of your machine the hard-code reads the custom values from the config.g file to know how to excecute Gcode for your specific LUTUM model.

Some instructions depend on separate macros that can also be altered by the user.
The Pause command, for example, lifts the nozzle 50mm and then moves it to the Y0-X0 location at a certain speed.
By changing the instruction of the Pause.g macro you can change this specific behaviour.

This is also the case for Home-all, homing specific axis and the Resume button.

On the other hand there are also instructions that depend only on the values from config.g. Specifically the ‘move’ commands take speeds and accelerations only from the config.g file. You can have very safe speed values in the macros and still have unsupported speeds in the config.g. As long as speeds in your gcode print file are within range you would not notice the issue until you excecute a move command via the touchscreen or browser interface.

With the steps described in this article the safe upper speed limits are defined in the config.g file.
The macros are adjusted to optimize speeds for their specific use.

Config.g the master file

Locate the config.g file. and click on it to edit.
This is the master instruction file, these values regulate the overall behaviour of your machine.
Make sure you only adjust the values described here.



There a 3 values that need adjustment. Locate the lines starting with M203, M201 and M906.

M203 X9000.00 Y9000.00 Z700.00 E2400.00:2400.00:2400.00
M201 X200.00 Y200.00 Z40.00 E5000.00:5000.00:5000.00
M906 X900 Y800 Z2300 E900:900:900 I10

M203 sets maximum limits for speed,
– for Z this should be no more than Z700.00 for LUTUM5 and 5M.
– it should be no more than Z500 for LUTUM4.6 and 4M+.

M201 defines accelerations.
– for Z this should be no more than Z40.00 for LUTUM5 and 5M.
– It should not be more than Z30 for LUTUM4.6 and 4M+.

M906 defines the maximum power (current) the Z motor can receive.
– this can be increased to Z2300 for LUTUM5 and 5M.
– it can be increased to Z1600 for LUTUM4.6 and 4M+.

Alter only the highlighted text, then double check if you only changed those parameters, then save the file and reset your machine.

Homeall.g

This is normally the first instruction you execute when starting the printer.
Locate the homeall.g file. and click on it to edit.
This macro holds the actions it needs to execute when you press the ‘home’ button.

Alter the two values highlited in the picture above then save the file.

homez.g

Locate the homez.g file. and click on it to edit.
This macro holds the actions it needs to execute when you press the ‘home Z’ button .

Adjust the highlighted text and save the file..
For LUTUM 4.6 and 4M+ the value should be no more than F500.

Pause.g

Locate the pause.g file. and click on it to edit.
This macro holds the actions it needs to execute when you press the ‘pause’ button during a print.

Only the highlighted value needs to be adjusted then save the file.

Resume.g

Locate the resume.g file. and click on it to edit.
This macro holds the actions it needs to execute when you press the ‘resume’ button that can be selected after a pause command.

Your resume code could look slightly different.
Alter it to resemble the code above and save the file.

G1 R1 X0 Y0 ; go to 5mm above position of the last print move
G1 R1 X0 Y0 F800 ; go back to the last print move
M83 ; relative extruder moves
G1 E1 F800 ; extrude 1mm of filament

Done

Turn your machine OFF and ON or reset it through the webbrowser with the emergency Stop button. All the new settings come into effect.


Lots of people ask us where LUTUM printers can be found.
We made a map, and on this map you can find the locations of most of our LUTUM clay printers and other LUTUM equipment around the world.

You can also Explore the intercative map on google maps.

This is no april fools, it’s a new clay extruder from VormVrij 3D.

Adjust Z speed setting of your printer

The first models of LUTUM 5 , 5M and 4.6 have shipped! They are equiped with a brand new brain compared to the previous models and we are still adjusting and finetuning behaviour of our machines for optimal performance.
The past few months we noticed that the Up and Down movement of the X arm along the Z direction stalls in some cases. After investigating mechanical and electronic parts it appears most of the stalling can be solved by lubricating the Z axis more often than previously advised.
Adjusting the motion setting of the various macros and and speed limitation settings underlying the Z-movements gives a reliable permanent solution, however, frequent inspection of the Z-spindle lubrication condition is still recommended!

It is easy to adjust

The good news is that it is easy to adjust and at the same time learn a bit about the workings of the hardware-software symbiosis of your machine.

Below are the various steps explained to alter settings on your machine.
All steps are done through the browser interface of the printer. If you have to log on to your LUTUM via the printer acces point you might need to open this website on a different device so you can follow the steps while logged on to your machine.

First open your web browser and log on to your printer, then locate the system folder through the LUTUM UI.

We have been working hard to deliver a more affordable extruder for our LUTUM® printer. The eco extruder is a workable solution that provides expected high quality print results for the smaller DIY projects or the experimental clay print setup. This extruder is not intended for high volume or professional scale printing.
While we have been testing this extruder for a few months and so far did not experience any deterioration in print quality we can’t predict how it will wear over the time of several years of intensive use.

As explained it is a budget extruder and we present it in several packages.

  • The standard package has de eco extruder bundled with the metal cartridge and 1 extra empty PET sleeve.
  • You can opt to purchase the eco extruder only.
  • A DIY set for self assembly, you can include a metal cartridge if needed.
  • A DIY kit where you collect the plastic parts and the Auger screw from ShapeWays.
    The remaining parts can be purchased elsewhere or from us.

Bundle with the eco extruder.

This bundle has you set and go within the hour.
You will receive the wiring instructions to connect a standard UTP/RJ45 to the extruder, the other (wire) side of the cable needs to connect to your printer electronics to send the stepper signal to the nema17 drive motor.

C;ay Extruder for LUTUM

Eco extruder only.

You can also choose to get the extruder without the bundled clay cartridge.
If you own an older version LUTUM® v3.x or v4.x and you want a budget replacement this is your pick.

Both sets are also available as a full DIY kit.

Clay Extruder

The DIY kit from Shapeways does not contain the Stainless steel auger screw. A steel-bronze aloy variant can be purchased from Shapeways instead.
However, all parts from Shapeways wil need some degree of post processing before assembly.
The Auger screw surface needs sanding for proper function.
The Plastic parts need to be bored to make essential inner surface smooth enough for proper printing.
Detailed Instructions are delivered with the parts.

Go to our RECOURCES page in the ” Support & Answers › mechanical › Budget Eco Extruder ” section.

Speficiations.

Clay Extruder

The extruder needs four M5 threaded holes to mount.

  • standard G1/4″ thread on the barrel, standard G3/4″ thread on the clay inlet side, the auger is SLS printed from stainless steel.

There are two seals inside the extruder.

  • a small O-ring holding seal and a 10bar pressure seal around the extruder.

Plastic parts are made from Grey Nylon and produced by a HP printer.

The package contains:

  • extruder
  • 1/4″ male PP black Leur nozzle adapter
  • five 1.4mm standard green nozzle tips
  • 10mm barrel cleaning brush
  • 4x M5x35 hex bolts for mounting to your equipment

What can you print with this extruder?

Any standard Stoneware clay can be printed as long as it has the proper viscosity. When you can hand sculpt it with ease, it’s normally okay. This definition holds for earthenware clay and clay with grogg content up to 25% 0.2mm particle size. Any other pastes with similar reology can be printed in theory.
Pure porcelain is not possible without specific additives, premixed porcelain developed for 3dprinting with our LUTUM® can be purchased from Imerys France.

Important to know.

The Eco extruder bundle and kit are shipped world wide.

The DIY kit requires basic technical skills, soldering equipment and standard workshop tools.
You also need an electrical drill and drill bits size 3mm,10mm, 10,5mm and 11mm.

A short guide to print this well known 3dbenchy benchmark and test your printing skills.

Printing 3Dbenchy with clay.

A short video taken while printing the Benchy.

I finally printed the 3Dbenchy with our LUTUM® clayprinter. This was a lot easier than I expected but it did take some time to get the slicing parameters correct.
To slice the file I used the Prusaslicer version 2.2.0. At the end of this article I will give all links, the 3Dbenchy STL file and gcode files for your LUTUM® printer if you want to try right away. After downloading 3d benchy from 3dbency.com I noticed this object was very small. First thing to do was to choose my nozzle and layer size and scale the benchy accordingly.

The excellent features of prusaslicer allowed me to check the slicing result for difficulties with clay. I tried to get the critical vertical shells to print without any infill. This was particularly important in the upper section of the little cabin. The small window sides will wobble a lot and I wanted to keep the nozzle passing in those areas to an absolute minimum. I found the optimal Scale at 300%. However, as I saved the STL file earlier at 250% I had to scale it up in slicer to reach the desired size. If you slice this print yourself using the download from this website, please scale it 120%.

3dbenchy rooftop in clay.

fig.01 testing


Next I tried to print the top section of the cabin a few times before starting the full print.
Getting the slicer settings and printer settings correct for that part of the print was most important as the rest of the print looked less difficult.

A little note on slicer and bridging parameters, the standard multiplier is 1 and that is way too much for clay. Try a few times to get it correct.
– When using the 1:3 ratio (layer height : nozzle size) I found the multiplier to be 0.65
– With the 1.25:3 ratio the multiplier had to be set to 0.5.

3dbenchy ceiling

fig.2 pictured is the standard 1 multiplier for bridging


After getting all settings correct I set to print the file, this worked good enough but not perfect as the little window sides were still very wobbly during the print. In the end the print sort of solved itself but the result was a bit af a skewed chimney as the ceiling could not hold the weight of the clay above. A solution was to fix the file by introducing a small beam under the roof to hold the chimney. I also made a few connecting strands of clay between the little window and door sides to keep them a bit more in place, this works but is still not optimal. However, The result is very promising. (I had to lower the Flow to 50% from the standard file as I forgot to reduce the pressure to accommodate the 3mm nozzle)

3dbenchy bridging in cabin roof

fig.3 STL file adjustments.


If you like to try this print yourself you can download the gcode files below. These files were sliced for the LUTUM pro+ and might stall your machine, if it does, lower the print speed with the control box until it prints properly.

G-code files for LUTUM:

If you like to slice this file yourself using the settings I found, you can download the configuration bundle. This can be imported into Prusa SLicer to take effect. Note that you might need to slow down the printer or lower printspeeds in prusaslicer if your LUTUM stalls or skips steps.

Important for this print:

First BRUTUM mega print a ceramic heat-exchanger concept.

A short registration of the first large clay print made with our new BRUTUM® concept machine.
The print took 48 hours to build with a 3mm nozzle and 1mm layer height. It used 25kg of clay.

You managed to Dislodge the X-arm from the vertical mechanics in the Z-Pole…

How to solve this quickly.

The bronze Z-spindle-nut is dislodged from its aluminium socket.
This is normal for emergencies when the X-arm is moving down lower than physically possible or because of an obstruction on the Print bed or because the long nozzle is attached but the Z slider was not moved up to set the correct zero point for Z homing.

What you need to do is to take the power off the printer.

1 person needs to hold the arm up.

The other person needs to move the Bronze nut up towards the four slides (openings) on the back of the vertical arm to visually inspect the situation.

  1. Use the wheel on top of the Z arm to move the Bronze nut up.
  2. Hold the nut with a screwdriver Through the side slid running along the Z-pole while turning the wheel.
  3. Turn the Bronze nut in the correct position so it can slide into the socket.
  4. Slowly slide the X arm down and place the nut back into the socket.
  5. You might need a small hook or screwdriver to push/pull the Z-spindle so that the Nut aligns perfectly with the socket.
  6. It is a very tight fit, but it does fit.

Once it slides in make sure you do not lift the arm assembly while holding the X arm as you would dislodge the Nut again.

Done!

Your Clay is the key to perfect prints

With the new universal Pugmill Adapter you can quickly refill your empty clay cartridges. The design is adaptable for most pugmills with a clay outlet between 70 and 80mm.
The kit works for both the 750 and 1500cc PET sleeves.

You can order an additional tubeholder for the 3000cc BRUTUM cartridges.

To deliver the correct Adapter for your machine we need pictures and a sketch of your pugmill clay outlet. Specify exit opening diameter, flange outer diameter and the center diameter of the bore holes.
In addition measure the size of the boreholes.

We will drill corresponding holes 2 mm bigger so the bolts will always fit.

I often get asked why we designed our printer the way we did. Why we use air and auger for clay delivery, why our printer is black, why we want to print with clay.
Today I am going to answer just one question. The extrusion technology and the idea behind it.

As you might know there are currently several solutions to 3dprint with clay. In 2014 there was only one option. Direct extrusion via compressed air. A technique put forward by Jonathan Keep and Dries Verbruggen. The results were often rough and very craft like in appearance. While they had ventured into the area of controlled extrusion with auger and piston style systems it did not reach sufficient print results to go mainstream.

Today, anyone starting to print with clay on DIY printers would start with similar continuous flow principles. It is simple, cheap and easy to design. But there are limitations to what can be printed on such a setup.

When we started 3d printing clay we quickly reached the end of diversity in our prints and within a few months of experimenting we found that consequent designs were all adaptations of earlier solutions. It became clear we had to redesign the way we would control clay output to reach a level of printing capabilities on par with regular 3dprinting.

There were a few restrictions we had to consider if we ever wanted to commercialize this technology. While we needed high precision and controllability it also had to be cheap, safe, reliable and manufacturable.
We started with cheap prototypes from simple bits and pieces found in hardware stores. While the proof of concept of auger extrusion was shown the print results did not meet our own standard, and we decided to leave the path of economics and went to design a new system from scratch.

The first thing we were concerned about was the volume of production. Not the clay prints produced by the printer, but the actual extruder itself. For example, to create the auger part of the extruder we had to contract a specialist CNC lathe company. One auger would become prohibitively expensive to make unless we would order a few hundred at a time. This would pose a serious risk, as we would have to sell our stock before we could develop improvements. The only solution would be to 3D print the metal parts we needed. This was more expensive but gave us the possibility to gradually imrove our technology without huge initial investments. We produced batches of ten printers at a time and improved upon that batch with the next batch of ten.

Since XYZ movement was straight forward the focus went to the extruder.
One of the more complicated parts was the delivery of clay to the extruder. How to move the clay from place A to place B with as little effort as possible but with high reliability.
We sticked to the Large Clay Vessel and compressed air as we had much experience with such a system while printing without an Auger. Clay and compressed air dynamics were somewhat understood and we thought we largely knew what to expect when building on top of such a system.

Five factors emerged which were crucial to get good extrusion.

– the strength and rotation speed of the motor
– the way the clay is received by the Auger
– the shape of the Auger
– the seal of the system
– the shape of the nozzle

To keep the design flexible and simple opted for manual air and manual adjustable rotation settings via firmware of the printer. This solution would provide a fixed nozzle width for a Gcode design file but flexibility towards the properties of the clay.

The motor requirements were quickly established as a regular 4N one had a hard time to move the clay, especially with large volumes. A geared motor proved a good solution and we have stuck to that ever since.

The way the clay is fed to the Auger was also found reasonably fast. It’s slightly different to regular Auger systems where material is fed in a type of trough where the auger turns at the bottom.

The tip and seal of the system had to be made from standard parts as those would wear or damage first. To release the pressure on individual seals we decided to spread the load by using three seals in sequence. Grease mixed with clay would act as the bearing and pressure cushion around the shaft.

It turned out that the tip at the end of the extruder was responsible for much of our frustration during the design proces. Since we started with continuous flow extrusion we really appreciated the freedom of nozzle size to dictate the width of the extrusion.
This freedom had to be translated into the new auger based design.
Unfortunately tip size has direct relation to the pressure needed to extrude clay. The smaller the nozzle the higher the pressure at the end of the auger needs to be. If the clay is not the right viscosity this pressure could result in segregation between clay particles and water.
Water would be forced up and dry clay would go down clogging the system and worsening the situation. On top of that particle flow dynamics around the auger itself also make things difficult.

Our first design still had to use fairly soft clay. Because we used tubed delivery this was not an issue. Our first line of extruders were performing well. They would extrude clay fairly constant, had no particular signs of wear (apart from the occasional seal) en were easy to operate.
But the results were still not perfect. Air bubbles and other irregularities in the clay would give errors in the print which we did not want.

Don’t get me wrong, I love the randomness of clay printing, the results of poorly mixed clay can by quite fascinating. But from a technological point of view one also had to be able to print perfect, all the time for days in a row if this machine would become a reliable partner in any production facility.

So we turned our focus to clay and how clay was prepared normally. Immediately pug mills and hand presses came into view. Most ceramist had one of these already and while we recognized these as a practical solution to mix and de-air clay, the viscosity was very different compared to the clay used in Air and tubed delivery.

We had to move the clay closer to the Auger and developed the micro cartridge for that purpose.
This proved a fantastic solution, the clay would enter the Auger with much lower pressures compared to our tube fed system. And without the tube the clay latency by compression went almost to zero resulting in even better control.

But we had to redesign the auger or change to a different motor to cope with this tougher material. We tried both, a reduced 12N motor did the trick. Clay was pushed through and we could print with much harder clay than before. Unfortunately the Auger was not the right shape for this clay. It took another few weeks to get the correct design conditions and build an auger that would properly move hard clay down a tube. We did realize that the difference between grogg and hard clay was smaller compared to our previous viscosities and to our delight we could push grogged clay with the same ease as regular clay.

Our new extruder design in combination with the small cartridges holding about 1kg of clay has given us a tremendous freedom in design and we feel we have reached almost the same level of control as printing with plastics. Of course clay has its own particulars, like shrinkage, gravity, vibration and climate sensitivity, but when taking those conditions into account we can print nearly everything.

A disadvantage of this solution is the need to regularly swap cartridges. Especially when printing a lot or large objects. If the clay between swaps is of different consistency this will result in an obvious seam. Great care is needed when preparing clay and cartridges need to be numbered to minimize seam issues.

Switching a cartridge takes about 15 seconds. Another minute to normalize pressure in the tip. Using the swap cartridge feature in the firmware to expel contact air and excess water reduces print irregularities. But that is a different story.

The Auger system is a simple ‘affordable’ system for controlling clay flow. Start and stop sequences are easy to execute. Compressed air is used to move clay to the extruder. Printing objects with 1kg (750cc) of clay is straight forward. There is the possibility to print bigger but that requires additional actions. Since almost every ceramics studio has compressed air most times there is no need to invest in a separate compressor. Nozzle size is variable but only up to around 7mm diameter. This system is optimized to create objects of small to medium size. You do need a Pugmill or mechanical hand press to get ultra quality prints. Compare it to filament quality, good filament gives better results. The same goes for clay.