Hello all!

In the process of rewiring my printer (getting rid of the pasta in the back) I did some sanity checks with a multimeter and I was shocked (not literally lol) to see that the ground connection to the printbed does not ground the entire frame (most likely due to the anodising of the extrusions).
If the anodising is non-conductive is there even a need to ground the entire frame? Or does a stray current penetrate the anodising and trigger the main fuse anyway?
If not: How can I ground the entire frame without dissassembling the whole printer and sanding away the anodisation at every contact point between two extrusions?

Just a question out of curiosity
Where and what for do you use machining (milling, turning) for your 3D printers or in conjunction with your 3D printed projects?

I will start with a few parts that I did:

This is an extruder drive wheel made from brass:

I also made my own heater blocks ('cause I'm cheap and milling is fun). The left one is one from china in comparison:

Here is a custom cooling block for a tilting extruder (which was later replaced with a watercooled one):

For the cooling blocks I also had to make an M7 tap...

And finally some brackets for an absurdly overpowered 32 mm ball screw that I got from eBay for next to nothing. To be fair, my printer is quite sturdy and heavy (about 25 to 30 kg for the whole thing) but that ball screw still is completely overkill. That's why I'm also using it as a 'guide rod' for the print bed (which in theory isn't very good practice but since it came from a CNC milling center it couldn't care less about the side load). On the other side of the print bed there's a puny 16 mm rod to keep it from rotating.

I'm looking forward to see what you guys do in metal for your hobby!

Obviously it isn't clear...
The feature isn't something that helps during a print, just during setup and troubleshooting.

I'll try to make up an example:
Let's say you command your z-axis to move 10 mm. You look at your printer and you'll see the motors running and the bed moving.
But unless you put a dial indicator or calipers against the bed you'll never know how much it actually moved.
If your steps/mm are calibrated right then one could assume that your axis moved the right distance and most of the times that is true.
But let's say you're tuning in your accelerations or maximum speeds (or maybe even the anti-backlash but on your leadscrew which could produce too much friction if too tight): Unless the motor loses a lot of steps and makes horrible noises of you see the print bed stuttering there is no way of knowing if your motors can handle this speed.

So what you would do now (with my proposed feature):

1. Press the button "check for lost steps" (or however it will be called)
2. the axis (in this case the z-axis) will go to its homing switch
3. If the motor didn't lose any steps the distance to the homing switch is exactly the distance that you can read in your UI (-> the real position and the assumed position did match).
   But if any steps were lost the firmware would read the endstop as triggered before or after the distance that was displayed. The difference in mm times the steps/mm will give you a value for how many steps weren't performed.

I hope this makes it clear since I don't know how to make it clearer

@dc42 Sorry, apparently I misread your statement somehow. Thanks for clarifying!

@dc42
Two more questions after buying the Expansion Breakout board:

1. The differential enable pins switch between on and off with 5 kHz when the printer is idle and also when a move command is given (though the motors won't move as they are in alarm state due to the fast switching). Disconnecting the enable wires does work, although I'd like to be able to switch the motors off via software

2. Do I need to disable the drivers on the Duex5? When moving X or Y, there is a warning in the console that the phases might be disconnected (which they technically are, as there is nothing connected to the outputs). When I disable the drivers, the servo motors start moving very slowly upon startup of the Duet and on the PanelDue there is a warning about overtemperature of those drivers.

@dc42 Alright, thank you very much for the information!

Hi all!
I just wanted to confirm something from the documentation. First of all, my (soon-to-be) printer is a CoreXY toolchanger with six independent tools that runs with a Duet 2 Wifi and a DueX5. That means, from the 10 integrated stepper drivers I need 7 drivers for tools and Z axis. The XY system runs on two JMC stepper servos that I need to connect to one of the boards.
From what I read in the documentation, this is either done

• through the expansion header (which is occupied in my case)
• with the pass-through connector DB S/D/E on the DueX5 (which requires the board to be put into DueX2 mode which limits my available stepper channels?..)
• or through the CONN_LCD connector.

I plan to go with the last option as it doesn't seem to have any drawbacks. Is this valid?
Also I want to use the PanelDue 7i which I intend to connect with the four-pin connector. This won't allow me to use the SD card anymore but I'm pushing gcode over WiFi anyway.

I'll be very glad if someone could tell me that my approach is good or that I'm overlooking something.
Thanks and have a great weekend!

From my understanding about injection molding it requires very high extrusion speeds. In commercial machines they melt the plastic in the heating/compression zone and then push it into the mold via hydraulics (or maybe also pneumatics) in fractions of a second. So depending on the size of the mold even a high powered extrusion system from a 3D printer isn't gonna cut it sadly. But I like the idea, it's quite novel!

The WiFi version is v1.23 so that seems to be the current one.
I'll try using the new DWC before deciding if I want to go back. The new design has some improvements that I really like
Also, the .json files are now visible in the systems folder. My guess is that it has to do something with the option of storing the settings on local storage (although I don't know if "local" means on my computer or on the Duet).

The older firmware worked for me so I never bothered updating it. "Never change a running system"
Not having to change my config files convinced me to try updating the firmware and the DWC files. That fixed the scrolling problem but now I have to get used to the new look. At first glance I think I like it though

I haven't found the .json files in the DWC file browser so I suppose you can only see them when the SD card is plugged into the PC? This question is for clarification purposes only.

Anyway, thanks for your detailed answer Sometimes the easiest solution looks like the hardest...

Hello all!

Some time ago I encountered a weird problem within the Duet Web Control: Whenever there's a scroll bar in the browser window (like when viewing the G-Code file list) and I scroll down, it automatically scrolls to the top again after about two seconds. This is kinda annoying when editing the macros in the system folder because you have to click very quickly on the file or else you'll miss it.
I'm using Firefox version 86.0 but the problem exists for quite a while now so it's not that specific Firefox version. I've also tested Chrome Portable v89.0.4389.90 and the same problem occurs. So I think it has something to do with my Duet firmware but I don't know where to look. Any help is greatly appreciated

M115:
FIRMWARE_NAME: RepRapFirmware for Duet 2 WiFi/Ethernet FIRMWARE_VERSION: 2.02(RTOS) ELECTRONICS: Duet WiFi 1.02 or later FIRMWARE_DATE: 2018-12-24b1

Regarding the settings for the scope, I'm not sure which ones you mean.
The step pulses are what you'd expect but the DIR signal is not. On the picture you can see both signals, STEP on top, DIR below. The sampling rate probably isn't high enpugh to catch all the pulses (pulse width is set to 2 µs) but otherwise you wouldn't be able to see the whole spike on the DIR channel.

Hi all!
I'm trying to read the signals coming from the E2_STEP and E2_DIR pins on the expansion header with an Arduino. For every step pulse while DIR is high I want to increment a counter and for every step pulse while DIR is low it is decremented.
The problem I encountered is that the DIR pin doesn't have either a high or low state but instead just sends a positive/negative spike for each direction change. I checked this with an oscilloscope.
Is this the expected behaviour? From what I've read the DIR pin should either be constantly low or high.

Btw, I know that the Arduino Mega uses 5V logic and the Duet WiFi outputs 3.3V at the expansion header but for now this doesn't seem like a problem.