Prusa serial connection wiring

Sorry for lack of posts been away working at our holiday rental getting it ready for its firsts guests so been cutting signs for the doors and making welcome baskets and doing all the other fun jobs hanging mirrors pictures etc. so lack of sleep and having an ill baby boy as well. I am very tired

Oh, and my soldering idea didn’t work so it’s back to using brake out headers tonight. wish me luck as want to put this project to bed. (It did work had 2 wires the wrong way around)

my light reading.

Ok, I have figured out my issue got 2 of the pins the wrong way around somewhere pin 4 and 6 were reversed not sure how that happened so might go back to the solder idea as it works now. I am however getting a low power warning on the pi and have some calibration issues with the screen.

Finally working off wires alone.

the calibration issue i think i know the answer to there is a line of code i need to move out of the x11 folder that might be causing my issues. will try that tonight and see if it fixes this problem.

So i missed the following line of code after running this command and reboot screen fingers crossed it will now work again going to test this later as plugged pi in wrong again last night as was tired.

sudo mv /usr/share/X11/xorg.conf.d/40-libinput.conf ~/

Think the screen might have issues going to do a fresh install of the script as now nothing works on the touch screen.

going to run off the stand-alone power supply as the voltage is too low to run a pi3 so have ordered a micro USB brake out cable so i can solder to 2 pins on the pi to power the unit this will allow me to shut down the printer on a wifi plug.

test run before i hardwire it.

Octo pi active and working just got to adjust web camera to get better image will then configure octolaps for some great time-lapse action. have recycled camera mount from my CR-10 as simple to fit.

just testing a quick print. on it to make sure it’s all working before i do a test fit of the control panel
2 test prints later. time to address the limited power.

I will cover the modification i will do to the link wire of the pi in a later post happy now the mk3s actually turns on and powers up.

then it stopped working yay back to USB method for the moment. till have thave some time to look into a fix.

Update think it is the cable as next post shows i think.

Prusa Mk3s Pi3 control panel intergration.

As i will be adding a Pi3 and octopi to manage and control my machine i was trawling through Thingiverse i spotted this little beauty. Thought would save me space and can integrate with the Prusa machine i also have 3.5 TFT adafuit display kicking around my bedroom.

Got this remixed design from FlyByTom this version V7 with no end cap. i went with this design will completely integrate into the panel this will mean can plug into the pi3 for USB and network connections when. I will be using the jumper pins from the back of the TFT screen to the Rambo board this will power the pi and integrate it into the printer. The link for the design can be found here

Downloaded and jumped into Prusa Slicer followed the instructions and put it on the plate at an angle so it will fit.

ready to print.

i am going to print in PETG when i do the final print but for a test print i have some black PLA kicking around the cave so will do a test run. Then print in petg later as I have 3 rolls kicking around that i have been meaning to print with but that will be a final print later.

The test Print and fit:

6hrs it printed in came out not half bad there was tiny amount of lifting in one corner

The wiring of the PI3 into the Prusa Rambo board. This is going to be slightly different from the guide on Prusa’s web site as will be wiring from the front of the PCB. found someone who makes cables but unfortunately, they don’t ship to the UK so going to have to make one my self.

There are six wires need to link the machine to the pi bank of 4 and 2 are used. so from the Rambo PCB, you will use the following

Pins used on the Rambo board.
Connections like so from the Rambo PCB

so to make this as i had no 7 pin connecors i glued a 6 x2 connector and a 2 pin connector together to make it a 7 pin connector. used some breadboard to hold it all together whilst the super glue set.

nicely glued up. ready to solder the other end.
Rambo connector cable i made for linking to the pi3 plugin and play.

Now a direct link would be too easy as the TFT screen uses all 40 pins in connection there is a break out header shown in PCB diagram below but too tight to attach connector did try.

failed attempt as heads too long.
JP1 is the brake out connector. only interested in the first 16 pins.
pins used in the PCB pinout diagram.

as the pin headers are too big so going to have to solder to the pi 3 directly so ignore above brake out wiring will be same pin numbers on the back of the PCB board going to flux and add solder to the 6 pads on pins 4,6,8 and pins 15, 16. I ran out of time to tin wiring and solder and test on Tuesday.

What it looks like wired up.

building the system:

This was partly straight forward partly frustrating as not all guide work. heres here’s my simple version of the guide this guide is if you are Using Adafruit 3.5 TFT display

You will need to download the octoprint image from

you will then need a program to burn it to your sd card i use etcher select image select sd card and write 20 mins later will have a working image

Put install screen to the raspberry pi add the SD card and network cable then power the pi will take a few mins to power up the screen will show just as white don’t panic.

scan local ip network for pi in my case showing on my network as using a ssh client login to the system using user name pi and raspberry as password.

Time to install TFT screen drivers this will get the screen displaying correctly. in the ssh, terminal screen type the following.

  • cd ~
  • wget
  • chmod +x
  • sudo ./

when installing the script you will get asked the following. what screen it is in my case option 4 3.5″ 480×320. you will also get asked if you want the screen to display consol. i said no and yes to HDMI port mirroring just in case i decide to use the HDMI port. You will then be prompted to reboot the machine say yes.

you will then need to relogin to the pi.

As octoprint image does not have graphical front end is web-based. We are going to first have to install the X desktop environment, then Touch-TFT and its requirements

  • sudo apt-get install libgtk-3-0
  • sudo apt install xserver-xorg xinit xserver-xorg-video-fbdev

Once X is installed, we can follow up with the installation of OctoPrint-TFT you will need to first of all download by using wget command.

  • wget

You will then need to install the script.

  • sudo dpkg -i octoprint-tft_0.1.2-1.stretch_armhf.deb

You will need to set the graphics output.

  • sudo systemctl set-default

We need to remove the 99-fbturbo.conf file from our Xorg directory. i tried this but didn’t find the file still works without it. so unsure.

  • sudo mv /usr/share/X11/xorg.conf.d/99-fbturbo.conf /usr/share/X11/xorg.conf.d/99-fbturbo.conf.old

Now on reboot OctoPrint-TFT should load and start attempting to connect

this was in the hose so no printer connected.

On reboot, you will see this screen until you plug it into the printer. you will then control screen as shown below. as i haven’t installed my link plug into the Rambo yet this was just to do a test to make sure all was working.

testing the server works. need to mess with the style sheets

now to configure the web interface of octopi.

Open web browser goto IP address or octop.local you will be greeted with a wizard so set user name and password and enable security. name profile of printer and set bed sizes in my case 250mm x 210mm x 210mm i also adjusted temperatures to match my Prusa printer in the configurations folder.

i will be adding plugins but will cover that in another post.

i will finish off this project on my return to London as got a 208-mile drive down to Wales for a weekend of getting holiday rental ready for first guests.

so will plug everything in on Tuesday.

Sunday Night Fun with Prusa Mk3s upgrade

As it was Sunday night and wet i thought i would bring the Prusa in for its upgrade as its time i fixed it once and for all.

One of the perks of being a Prusa owner is when new tech is produced they release an upgrade kit. So armed with a Pepsi Max cherry my electric micro screwdriver a pair of pliers and a screwdriver i set to work.

sunday night fun ready to start the upgrade

got the footstool and a box and made a little workshop in the living room as my little one was in bed.

All stripped down box of bolts removed time to upgrade

so after 30 or minutes or so i had taken apart the old extruder and was left with bare z-axis ready for its new extruder to be installed. now to install the new extruder.

Do love the online manuals nothing missed. what you see on the screen is what you need to do.

about an hour and 30 mins into the build and starting to button up the extruder getting ready. for electronics. section of the upgrade

All done 2 hrs later yes i missed some square nuts and had to rebuild x backplate again doh missed that section of the manual it’s fine as was easy enough to do. right all built.

Downloaded latest software and firmware of the Prusa site ready to flash it. all done flash successfully. Time to calibrate my machine and hope the upgrade has fixed it. here goes nothing. ok seft test passed auto home passed XYZ calibration failed arg going to call it a night as 1 am in the morning on a work night.

Monday evening feeling bit on the tired side. I have managed to speak with tech support online chat and was asked to check the P.I.N.D.A probe yes think i must have been tired as had not plugged it in last night doh. Ok, let’s get back on to the calibration one last check of the P.I.N.D.A probe hight and found it needed some minor adjustments. time to calibrate

4 point calibration to start off with fingers crossed.

Yay, its passed all calibrations and have dialled in the first layer hight. done a simple test print all working. time to move it back to the cave. time to test it’s all working. first long print. 12:30 am fist layer looks perfect time to sleep.

have checked on it this morning and its still printing. So i think i have solved issues with my mk3 will post an image of first printed half of the spool holder later on my return home.

Will put an image of the first half printed later here

That one working Prusa Printer now to fix the Mk2s MMU as then can print multi-coloured prints. without the expense of pallet 2 +. Fingers crossed on that one as then will have a full set of working printers at home. That will probably be on my return from Walse as got a house to get ready for our first renters so a busy week/week end.

Will be printing 5 spool holders so i can have a full set of multi-material printing and the mk3 at the same time.

Time to Upgrade my Prusa

Todays Arrival:

Prusa MK3s Upgrade Kit today so better get refreshed on the disassembly of the extruder for the new filament sensor. As i thought that the doorbell went and DHL delivery from Prusa research lol freaky

decided to get the version with the printed part as the printer is working intermittently.

Black Elegoo Resin is arriving so can finish off relocating the USB plug might also give backplate another go. should have this before the end of the day. depending on amazon some time erratic delivery.

Last nights offerings.

Curing station was going to do it last night but got home and by the time i had fed and watered the son put him to bed was late so i just tinkered with the mk3 Prusa and managed to get it to Print a job with only one filament reload.

I then called it a night as was wet and felt like some PS4. I know i don’t post every day on here but bits are constantly going on in the background whether its day job or crafting business or fun projects and unlike the greats of web and youtube i am a one man operation and i love it.

Tonight will be a washout as at a wedding hoping to get some the upgrade done over the weekend. time allowing as looks like quite a few steps are needed.

Was a productive night in the cave bit of modding and crafting.

After looking on the Elegoo mars forums i saw someone had reworked the firmware to allow network support so i had to do it.

you will need to register to download the firmware modification then unpack it for installing it to the machine the script comes with great instructions. the

I then found a great design on Thingiverse that allowed for a keystone network adaper to be installed to a cat5 cable. so i jumped on amazon order some keystone plugs and now to convert the firmware and add the hardware.

Last night i printed and cured the new black plate on the printer.

So modifying my new printer begins
1hr later time to cure the back plate.
Ready to install later.

Thanks, prime as next day delivery for my keystone plugs and tools to do this had a load of patch cables left in the office so going to sacrifice one of them as my plugin and play solution. all my bits are paid for not sponsored just like the service.

goodies for the mod.

time to make a short network cable to keystone connector. armed with my cable stripper and punch tool time to cut down the cable and make it panel mounted.

All done and tested.

unfortunately, i managed to install plug backwards and broke the print on removal. so will be a tomorrow job as currently printing a USB mod for moving the key from back to front.

USB extension cable ready for next mod.

Updated from yesterday 02/10/19:

The right printed the rear plate again, guess what i managed to break it again so i think will print it in pla once i have my Prusa back up and running right.

I am hoping to get an upgrade on Monday and be back in business as driving me nuts not being able to use it. will also revisit the MMU of my mk2s as could be good fun.

I have ordered some black resin and will reprint the bottom part of the USB holder in black but works well. some pictures of it in green.

going to reprint in black as all green is too much.
base to ve redone in black and keep top green. for the time being.
%d bloggers like this: