E3D toolchanger: Tuning the tool pickups with reprap global variables and macro’s assistance

After I installed the homing switches for X and Y on the E3D toolchanger, I finally had a decent starting point to get the tools pickup and parking tuned.

Originally, I used sensorless homing but this caused changing offset values of the X- and Y positions of the machine. So the tools could not be picked up or brought home consistently after a reset.

Now, everything works fine and the X-Y values don’t change anymore after a reset.

What I dis was to first make some macros for a one-off setting of the X and Y postion of the 4 Tools for the toolhead’s positioning.  If you don’t do this, you have to change all X values manually in 8 macro’s every time you want to change the value of X.

This was done with a number of global variables.  After defining these in a macro, they need to be called before using them.  In Config.g, I made a reference to run  the macro of the globals.g macro so it runs every time you boot the Duet.

In config.g, after the Tool definitions I added the M98 code to start the global definition of the used variables:

M98 P”0:/sys/globals.g” ; Make global variables in this globals.g macro

This macro file looks like this in my case and please be aware that the actual variables will differ per machine, but this may give you a starting point:

global T0_X_dock=-12.3 ; X-Parking position of Tool 0
global T0_Y_dock=225.2 ; Y-Parking position of Tool 0
global T1_X_dock=80 ; X-Parking position of Tool 1
global T1_Y_dock=225.9 ; Y-Parking position of Tool 1
global T2_X_dock=212 ; X-Parking position of Tool 2
global T2_Y_dock=226 ; Y-Parking position of Tool 2
global T3_X_dock=304.7 ; X-Parking position of Tool 3
global T3_Y_dock=225.4 ; Y-Parking position of Tool 3

The tfree 1-3and the tpre 1-3 files will then be like this for T0, and you can make the others by just fulling in T1 , T2 or T3 where it now states T0:

; tfree0.g
; called when tool 0 is freed
G1 Z4 F1000
;Purge nozzle
;M98 P”purge.g”
;Move In
G53 G1 X{global.T0_X_dock} Y150 F50000
G53 G1 X{global.T0_X_dock} Y200 F50000
G53 G1 X{global.T0_X_dock} Y220 F50000
;G53 G1 X{global.T0_X_dock} Y{global.T0_Y_dock} F1000
G53 G1 Y{global.T0_Y_dock} F1000
;Open Coupler
M98 P”Coupler – Unlock.g”
;fan off
M106 S0
;Move Out
G53 G1 {global.T0_X_dock} Y175 F50000

; tpre0.g
; called before tool 0 is selected
;Unlock Coupler
M98 P”Coupler – Unlock.g”
;Move to location
G1 X{global.T0_X_dock} Y200 F50000 ; was X-10.5
;Move in
G1 X{global.T0_X_dock} Y220 F50000
;G1 X{global.T0_X_dock} Y229.2 F1000 ;was f2500
G1 Y{global.T0_Y_dock} F1000
;Close Coupler
M98 P”Coupler – Lock.g”
;if you are using non-standard length hotends ensure the bed is lowered enough BEFORE undocking the tool!
G1 Z10 F1000
;Move Out
G1 X{global.T0_X_dock} Y150 F10000; was 4000

And I made some macros for checking where the toolhead is positioned, right in front of the tools T0-T3:

; fit_T0.g
; called to fit the Tool just in front of the dock
G1 Z4 F1000
G1 Y-10 F2000
G53 G1 X150 Y100 F20000
;Move In
G53 G1 X{global.T0_X_dock} Y150 F10000
G53 G1 X{global.T0_X_dock} Y200 F10000
G53 G1 X{global.T0_X_dock} Y220 F10000

If you want to check if you made the correct changes to globals.g, be aware that the new values in the globals.g variables macro will only be read when you reboot.  [If you want to redefine the values in any other way without rebooting, you will need another type of call function.]

E3D toolchanger upgrade: X-and Y- axis homing switches installing and configuring

My E3D toolchanger appeared to have some small inconsistencis in homing X and Y.

This became apparant after I tried to tune the exact positions of the tools pickup, after having homed.

Every time it was tuned, it worked well and the next day it was just a bit off. Then I retuned it again, and after a day it was off again.  Not a lot, but just 0.1 mm or a bit more.  But it did cause problems with the toolchanges.

So- after reading a bit I found that others had this problem as well and produced a solution: Just put in a couple of good X- and Y homing switches!

I even found the to be printed 3d-parts for mounting these switches. Thanx for this, folks!

The switches are the same type as for the Z-switch.

I printed the mounts in PETG carbon on my Prusa mini and mounted  both switches on the E3D toolchanger.

After this, I amended config. g and the homing files, please see the rest of my post for this:


; Endstops
M574 X1 S1 P”xstop” ; X min active high endstop switch
M574 Y1 S1 P”ystop” ; Y min active high endstop switch
M574 C0 ; no C endstop
M574 Z0 P”nil” ; no Z endstop switch, free up Z endstop input as Z endstop switch. (I changed  this part for correct working with RRF3.3+)


; homex.g
; called to home the x axis

M98 P”homey.g” ; Home Y always before homing X

G91 ; use relative positioning

G1 H2 Z3 F5000 ; lift Z 3mm
G1 H1 X-400 F15000 ; move left 400mm, stopping at the endstop
G1 X5 F15000 ; move away from end
G1 H1 X-400 F2000 ; move left 400mm, stopping at the endstop
G1 X2 F2000 ; move away from end
G1 H2 Z-3 F1200 ; lower Z

G90 ; back to absolute positioning

; homeall.g
; called to home all axes;

M98 P”homec.g” ; Home C (ToolHead)

M98 P”homex.g” ; Home X

M98 P”homez.g” ; Home Z

G1 X150 Y-49 Z20 F15000 ; Park

; homey.g
; called to home the Y axis

G91 ; use relative positioning

G1 H2 Z3 F5000 ; lift Z 3mm BED DOWN
G1 H1 Y-400 F15000 ; move to the front 400mm, stopping at the endstop
G1 Y5 F15000 ; move away from end
G1 H1 Y-400 F2000 ; move to the front 400mm, stopping at the endstop
G1 Y2 F2000 ; move away from end
G1 H2 Z-3 F1200 ; move Z BED UP

G90 ; back to absolute positioning

Z homing did not change and remains as is:

; homez.g
; called to home the Z axis
M98 P”Coupler – Unlock.g” ; Open Coupler
G91 ; Relative mode
G1 H2 Z5 F5000 ; Lower the bed
G90 ; back to absolute positioning
G1 X150 Y100 F50000 ; Position the endstop above the bed centre
M558 F1000 ; speed to 1000
G30 ; probe x 1
M558 F300 ; speed to 300
G30 ; probe x 1

Toolhead stepper fault and solution

The toolhead stepper of my E3D toolchanger system suddenly broke down.

The cause was a failed tool pickup move,  due to which the rotating axle of the toolhead pickup system got blocked.

After exchanging the stepper I changed the Duet’s settings so the C-drive will not be able to generate too much torque.

This will prevent the last teethed wheel to break whenever the driven pickup axle gets blocked under extreme circumstances.

After opening the case of the failed reduction box, I discovered 1 broken tooth of the final gear.

I ordered me a new one, and mounted this.  And I changed the C-drive’s settings to make use of the stall mechanism.  It took some tweaking to get this to work properly.  After all, picking up a tool must still work as this is the base intention.

All is OK again!

E3D toolchanger Hymera fans 2, 4, 6 and 8 intermittent problem solved

In the end, the solution to my intermittent on/off problem with my toolfans on the Hymera direct drives was extremely simple.

The picture shows the solution, as the Hymera stepper driver obviously interferes with the 40mm fans.  The problem was that these fans 2,4,6 and 8 not always started spinning.

I tried to exchange the fans which did not help, tested the Voltage, current , settings and so on.  Everything appeared to be OK.

Strangely enough, when testing the fan off the Hymera tool, even including the duct attached, everything woked fine.  Just did not work when mounted on the Hymera.

Finally, Just trying some things, I pushed a thin steel plate (NOT RVS) in between the fan and the stepper motor, and now it always works, even at 5% PWM!   Problem solved!

After testing at all tools, I made 4 better fitting thin plates and mounted these at the 4 tools and no problem exists anymore, ever since!

Custom E3D toolchanger Dock adapter plate

Jantec.nl E3D toolchanger Hymera DD DOCK adapter and 3mm shifted adapter download

Tool T2 and T3 (3rd and 4th from left) are about 1.5 mm apart in the standard build, which means that T2’s tool fan can draw almost no air. With the new custom adapter, the right tool T3 moves 3 mm to the right, allowing the left tool T2 to once again draw air with the clear fan and cool T2’s heatsink from the Hymera Direct Drive extruder.

With this custom adapter, the respective tool moves up 3 mm, giving you an extra 3 mm of space compared to the left tool.

This makes just enough room for the tool fan of the left adjacent tool to cool the heatsink.

So place this adapter in the 2nd and 4th places with Tool 1 and 3.

This will save the first (T0) and 3rd tool (T2) in terms of cooling!

On the left the original version, on the right my version modified in Autodesk Fusion 360 for the tools at position T1 and T3 (2nd and 4th)




Jantec.nl E3D toolchanger Hymera DD DOCK adapter and 3mm shifted adapter

Calibrating E3D coreXY 4-toolchanger 3d printer

I am in the process of calibrating the tools, the overall settings and so on so I can move on with the rest of the tools.

In doing so, I always set all tools to settings that are in comparison to the first tool, T0.

This way, should anything change,  I have a solid reference.

Tomorrow I will build and install the 2 other Hemera direct drive tools and possibly I can finally have my Benchy testpint made with all 4 Tools!


In the end, calibrating did not work very well and the solution is here:E3D toolchanger upgrade: X-and Y- axis homing switches installing and configuring  and E3D toolchanger: Tuning the tool pickups with reprap global variables and macro’s assistance

Building E3D coreXY 4-toolchanger 3d printer

Last week I ordered the E3D toolchanger 3d printer kit and today I built it (almost completely).

The delivery went a bit awkward from England, because of the VAT and clearance fees you have to pay in NL.

Because my Voron 2.4 is fast, but could not print everything in one day, I have to assemble 3 more extruders.

Below you can see my shot with a Hemera direct drive extruder mounted on the right side.

To be able to follow everything on the video, I set all of the tool change speeds to 10x slower for a moment.

After the first day of test runs I swapped the original Duet2wifi board for a Chinese clone.

From the clone the wifi is impeccable, but the new updated wifi module on the original Duet2wifi is also with all the updates not working properly.

Every time I perform a remote reboot after a config change the wifi crashes and the board eventually connects fictitiously to IP address

Searched all sites for help but found nothing.

Lack of experience can hardly be it, I have plenty of printers running fine on duet2wifi.

Just to be sure I have ordered an original Duet ethernet board, then I can convert the original board to duet2ethernet and I can at least still use it.

I ordered the version with 4 tools, the direct drive hemeras.  I also want to work with soft filament.

The nice thing about this experimental printer is that everything works with Duet, and I have quite a bit of experience with that.

The E3D TC will be my first semi-pro multicolor printer.

I have an Ender3 pro with MMU2S, an A30M with Chimera dual nozzle and an I3BearV3 with dual magnetic carriages.

But out of these 3 systems there is no one that really makes perfect prints.  They each have their specific qualities and features.

The Ender3/MMU2S can quickly print PLA and PETG with 5 colors but requires a filament spillage tower on the bed and is very cumbersome and slow to use.

TheA30M with Chimera is nice and fast and large (300x300x400mm) in build volume.  But the print quality is reasonable at best.  The dual nozzle Chimera with the nozzles at the same height hits with each movement just with the unused nozzle the tip of the filament deposited by the active extruder.  This results in smudges and a less beautiful print.  Yet I use this reasonably often, especially for quick test prints and at 0.2 0f even 0.3 mm layer height.  That works fine.

First impressions:

Please note that the Duex5 and Duet2wifi are initially incorrectly mounted here! The Duet must be below the DUEX5!

Here the object fan duct of the original version is used, I will update this later to the new version with the surround air ducts.

I printed everything with orange ASA on the Voron 2.4 at 150mm/s and 0.2mm with the E3DV6 direct drive Voron extruder and a 0.4mm copper nozzle.  Again, that went great!

By the way, there is something to note about this kit.

It is definitely not an ‘out of the box’ working system.

The hardware is outstanding, so are the manuals, better than anything I’ve ever seen.

The Duet and Duex combination is perfect and all the cables and screws, nuts, pins, gears and so on are nicely labeled and of fine quality.

The available config files, macro files and example print files are also great to start with.

And therein lies the problem for non-experts: All values are set to the best possible configuration.

And depending on your choices of extruder, bowden or no bowden and so on you have to make some adjustments here and there.

I had to recalibrate everything in terms of pickup Y values in the tool changer files before the tool was actually picked up and returned nicely.

In addition, it turned out that the tool pickup has to be adjusted very accurately to get the slot in and out of the extruder plates.

You have to understand how this is built, especially in the firmware.

Then you understand that the system has to reset to the start position every time at the start, and then the system makes that the reference point. Then you have to measure where 1) the open position is and 2) the locked position is.  Those values must be entered as C values in the pickup and return macros.

What I also find difficult is that there are no sensors (yet) to check whether the tools are in use or parked.

That means that you can just give a command to do a homeall while there is still a tool hanging on the pickup.

I would like to know that because then you program around that.

And so there are some other things like no filament sensor on the tools, no LED lights on the pickup but I’ve already seen a handy bracket for that.

So a very nice and good system, worth its money and high quality material, design also beautiful and still much to tinker with. Thank goodness!

In any case I’m going to reuse my Z-homing files from the previously built mullti- extruder machines with Duet.

Because this E3D works with a pre-homing without the tools hanging from the pickup, you will have to calibrate a Tool at Z distance relative to the pickup value every now and then.

And also the mutual differences in X and Y of course, relative to Tool0.

I have some nice macro tinkering for that too!

Next week onwards!

hole and pipe placed to adjust the magnetic coupling with the socket screw

Monoprice MiniDelta V2 GD32F103 ARM MJR83B motherboard

Today I opened the lid under my Monoprice Minidelta printer that I bought on Amazon end of last year (11-2021).

Unlike what I found on the net, I appear to have an upgraded motherboard that is joined with the TFT.

Both the MB and TFT have their own pocessor and -TFT update files, available from the Monoprice website and to be found on http://mpminideltav2.com/doku.php?id=octoprint:config.

The GD32F103 ARM processor is the 32-bits direct STM replacement and is a very capable processor.  The board also looks very good, so I won’t be replacing any of it.

I am however trying to build my own firmware for the MB, based on Marlin and the STM32 lookalike.  BUT- the LCD and the pin connections for the hardware ia all unknown to me, so it might take some more investigations..

For the short term, I will install a Pi Zero2 and adjecent PI IR camera in the printer, along with a top LED light.  The original new printer’s firmware allows the use of Octoprint so I can add this printer easily to my managed stock of remotely managed 3d printers.  Without modding the original firmware.

In the bottom of the printer, enough space is available to mount the RPI and I will switch the LED with the PI’s GPIO managed switches, and a MOSFET board.  Preferably with a PWM driver, or just on/off if this works better.

Another required upgrade will be to get a PEI sheet on the hotbed and replace the plasticy extruder with a dual drive one..

The optical Z+ endstops are OK!


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