Welcome

This page is about my interests, projects, and profession (technical artist in the video games industry).  Most of my hardware\software projects are coded in PythonProcessing, & Arduino.  I also enjoy 3d printing, you can find my designs for download over on Thingiverse.  More pics over on Instagram.

Find Processing\Android\Python programs\apps I’ve developed via the above title bar.

I also maintain several wikis on Maya\Python\Pygame\Processing that I update far more often than this blog.  See them on their page.

All information on this site is copyright under the Apache Licence v2.0, unless otherwise noted.  Which means you can pretty much use the information here for whatever you like, but I always appreciate credit where applicable.

Have a look around.  Thanks for stopping by.

— Eric Pavey

New cut: “Denali”

New 3D Print: Oahu 2.0

I was recently commissioned to re-3d-print my Oahu design from a year and a half ago.  Since then I’ve built a bigger printer (the C-Bot), the terrain2stl software has been improved, I’ve gotten better at painting maps, and I built an X-Carve CNC.  I’m quite pleased with the end results:

oahu_final_sm

Stats:

  • 3D printed in Makergeeks ‘Nuclear Green’ and ‘Soulful Blue’ PLA.  I paused the print and swapped filament to change from water to land.
  • From tip to tip, the 3d printed part is close to 14″ across.
  • Sliced in Simpilfy3D:  At 200 micron and 90mm\sec with a .4mm nozzle, it took around 7 hours to print.
  • Modeling for both the map and the blue acrylic was done in Autodesk Maya.
  • Terrain was captured via terrain2stl.
  • The blue acrylic was cut on my X-Carve CNC, toolpath generated by Easel, took maybe 10 minutes.
  • After print, I sponged on dark green spray-paint, and after drying, light brown on the mountain tops.
  • The models height is scaled up 2x to exaggerate the terrain.

Another angle:

oahu_perspective_sm

And the raw print:

oahu_unpainted_sm

If this is something you’d like in your home (or any other map) let me know and we can work something out.

Howto: Pause RepRap Fimrware for filament reload at a specific layer number

Like my previous two posts on the subject:

…since I’ve switched my C-Bot 3d Printer to RepRap Firmware, I needed to figure out how to pause it at a specific layer height in gcode.  The wrinkle this time is I have no LCD hooked up to it, so I wasn’t sure how to unpause it.

As it turns out, it’s darn simple (as it should be):  Enter a M226 at the line you want it to pause:

... bunch of gcode....
; layer 2, Z = 0.38
M226

And bam:  It’ll stop right there, executing what’s in your pause.g macro.  From there, you can change filament as needed, then enter a M24 (executing the resume.g macro) via a connected serial console to start the print back up.

Optionally, like mentioned in the above posts, you can use your slicer software (if it supports it) to post-process the gcode to add in the M226 where you need.  Look to those posts as examples of how to do this.

Note:  I’ve had this fail via Octoprint:  3 hours into a 6 hour SD print the gcode triggered an M226 where it was supposed to.  I watched as the print paused, and then I heard all the fans kick off:  The whole board reset, thus canceling the print.  I tried simple tests with Octoprint using small calibration cubes and got similar (negative) results after only a few lines of printing.  Doing the same tests via Simplify3D’s serial console (still printing off the SD) worked however.  In fact, as a sanity check, during the pause I’d disconnect S3D entirely and unplug the USB, then reconnect USB and reconnect the serial console:  I was able to successfully issue a M24 to restart the print, so right now I’m going that route if I need to do a filament change.

Installing RepRap Firmware on RADDS

Jump to C-Bot blog index to see all the posts.

This post can also be prefixed “Building the C-Bot 3D printer part 34:” 


Overview

This post covers the steps I went through getting RepRap Firmware (RRF) installed on my C-Bot’s RADDS/Due combo.   My goal is to lay out all the steps & pitfalls I went though to get it working, in detail, since I could find no page online that already illustrated this.  Even though I’ve used several other firmwares in the past there were may concepts that were new to me (and probably not new to those more experienced in programming), that I’ll hopefully illuminate to others that were as much in the dark as I was.

It is mainly about RRF, and not the RADDS hardware itself:  That is covered in depth by my C-Bot’s ‘Upgrade to Repetier‘ post, no need to dupe all that here.

For some context of my experience (and I’m not saying my experience is ‘high’, more of a squishy-medium), previous firmware/hardware combo’s I’ve used/installed/tweaked include:

  • Sailfish/Mightyboard on my Makerbot Replicator 1
  • Marlin/Rumba on my C-Bot
  • Repetier/RADDS on my C-Bot

Why do this?

I had two main goals for installing RRF on my C-Bot:

  1. See if these weird vertical lines that were showing up on my prints when I switched to Repetier/RADDS would go away (and also to check out it’s overall comparative performance differences):   I figured this had something to do with Repetier & CoreXY printers.  As it turns out, it does not:  The same lines still show up in RRF :S  You can see pics of that issue in this Repetier Forum Post.
  2. Does firmware designed for 32 bit hardware have a leg up on firmware (Repetier) ported to 32 bit hardware?  The jury is still out, but my initial impressions (now that I’ve been using it for a few weeks) are positive.

Resource Link collection by webpage

Notes on RRF & it’s history

Big Thanks

Goes out to Dan Newman for his patience & tireless forum replies helping to guide me through this, plus other forum posters David Croker\dc42 (who helped write the dc42 fork of RRF) and GroupB.


My build environment

Hardware

  • All of this work was done on an ancient Macbook Air running OSX Yosemite 10.10.5.
  • RADDS 1.5
  • Arduino Due R3 (Note, that version of the Due has a ‘reset bug’, described below under ‘Issues’.  You want a Due R3-E to avoid this issue).

Software

  • Mentioned below, I installed the older Arduino 1.5.8 to get access to Bossac.
  • I do my text editing in Sublime Text 2.

Build from source

Docs: https://github.com/dcnewman/RepRapFirmware-RADDS/blob/master/INSTALL.md

Note, I did not do this (build from source).  But I initially tried to do this thinking it was necessary, since this was all very new to me.  Scons is required to build from source, and I had a nighmarish time getting it installed, and around that time in the fourm posts someone said “why not just install a prebuilt binary” using bossac?.  Which I didn’t know how to do either :)  The key piece of knowledge from that was:

SCONS : Builds the source into a .bin
BOSSAC : Upload compiled .bin to the Due

For what it’s worth, here’s my notes for ‘building from source’:

Get the git repository

You’ll need this anyway even if you’re not building from source, since it has the precompiled binaries, plus example macros required later.

On my Mac, I have my git root set to:

~/git
$ git clone https://github.com/dcnewman/RepRapFirmware-RADDS.git

So it installs here:

~/git/RepRapFirmware-RADDS

Scons:

I could only get scons installed by doing a MacPort.  And again, you only need to do this if you want to build from source.

$ port install scons

And then spending an hour getting various packages updated.  It was a nightmare.

Get bossac & configure Arduino IDE

To get bossac (which you need to later flash the compiled .bin to the Due), you need an older cut of Arduino, 1.5.8:  I can’t seem to find bossac anywhere on my Mac based on the latest release.

https://www.arduino.cc/en/Main/OldSoftwareReleases#1.5.x

This is where you can find bossac on a Mac (note how I changed the Arduino App name so as to not clash with the more current install I also have):

/Applications/Development/Arduino_158.app/Contents/Resources/Java/hardware/tools/bossac

Since I’d already done it back when I installed Repetier, I’m not sure how important this next step isBut if you run into problems:  You may need to ‘install’ the Due board in the Arduino IDE:  The bare bones instal doesn’t know anything about the Due.  Check out my post here under ‘Configuring the Arduino Due with the Arduino IDE’ on how to do this.

I didn’t get any further, since at this point I realized I didn’t need to build from source at all…


Flash precompiled binary

Docs: https://github.com/dcnewman/RepRapFirmware-RADDS/blob/master/doc/RADDS-v1.5.md

You need bossac to flash a precompiled bin to the Due.  If you haven’t already get bossac installed, see the previous section for that.

BOSSA is an acronym for Basic Open Source SAM-BA Application.  Not sure what the ‘C’ is for…

There is a standalone app for this, but it’s known to not work with RADDS, so spare yourself the trouble.

Issues

I had a number of problems trying to flash the bin:

  • The Due has two programming ports, the ‘Native port’ (furthest from the barrel-jack) and the ‘Programming port’ (closest to the barrel jack).
  • You’re supposed to be able to flash the bin over the Programming port, only having to press the (easily accessable) reset button.  I could not get it to work.
  • The only other alternative is to use the Native port, but to do that, you have to first press the Due’s erase button, then reset.  Issue is, the erase button is completely hidden by the RADDS shield.  So I had to unwire everything from the board to get it out of the case, pry the RADDS shield off the Due, and do the erase\reset\native port combo. But, it worked.
  • It appears this “can’t use programming port” may stem from a firmware issue on the chip that drives the Due’s USB (discussed at the bottom under “issues”).  Basically, whenever you power on the Due, you must also press reset before you can connect to it.

You need to know what USB port the Due is on.  The easiest way I found this was:  Power it on.  Press reset to get around bug.  In either the Arduino IDE, or in Simplify3D (the slicer I use), see what’s listed to connect to.

You also need to know which binary to install.  There are multiple ones available in the /git/RepRapFirmware-RADDS/Release/ folder: I started with RepRapFirmware-1.09r-dc42-radds-b.bin, being told that was the most tested and stable at this point.  I quickly later upgraded to RepRapFirmware-1.13a-radds.bin, which has the advantage of allowing future firward upgrades to occur directly off the SD card.  See the notes here, and here.

Process

Based on the above bossac install dir, this is what I used to flash the bin to the Due:

  • Connect USB to native port on the Due.
  • Press erase on the Due.  I waited 5 seconds (not sure how long to wait but that worked).  Note if the RADDS shield is on the board and the erase button is hard to access, you can use a popsicle stick cut in half to reach it, with the help of a flashlight and extra pair of hands.
  • Press reset on the Due.  Again waited 5 seconds (not sure how long to wait but that worked).
  • Ran the below command:  The shell showed me the progress, with a successfully completion.
$ /Applications/Development/Arduino_158.app/Contents/Resources/Java/hardware/tools/bossac --port=tty.usbmodem2621 -e -w -v -U true -b /Users/<USERNAME>/git/RepRapFirmware-RADDS/Release/RepRapFirmware-1.13a-radds.bin

The short version (without paths) for readability is:

$ bossac --port=tty.usbmodem2621 -e -w -v -U true -b RepRapFirmware-1.13a-radds.bin

Note if you can get the programming port to work, you need to set ‘-U false’.

If performed successfully, you should see something like this:

Erase flash
Write 195708 bytes to flash
[==============================] 100% (765/765 pages)
Verify 195708 bytes of flash
[==============================] 100% (765/765 pages)
Verify successful
Set boot flash true

Test initial connection

Once you’re flashed the bin, how do you know the firmware is actually working before moving foward?  These steps will let you know it’ safe to continue.  You can do this even before the RADDS is plugged into the Due.

Reminder:  Connect the USB cable in in Native USB port (the one furthest from the barrel jack) of the Due, then to your computer (order doesn’t matter).

The Due ‘reset’ bug

Note, it appears that my Due has a bug with the chip that drives the USB firmware : Because of this, after I power it on, I must press the reset button (on the Due or RADDS) for the firmware to actually load.  I had this same issue using Repetier.  If you don’t press the reset button after it turns on, your computer may not be able to communicate over USB correctly, and you’ll spend hours searching the internet like me trying to figure out why.  This is discussed in more details in the “Issues” section at the bottom.

Three different methods I used to connect to the machine, immediately after flash.  I’ve listed the USB ports that I used below, yours will most likely be different.

Connect via Simplify3D

Press reset on the RADDS board.

Via S3d ‘Machine Control Panel’, connect at 115200 baud to USB port /dev/cu.usbmodem2621

See the section below for actually configuring Simplify3D for printing with RRF.

Connect via Arduino

Press reset on the RADDS board.

Tools -> Board -> Arduino Due ( Native USB Port)

Port -> /dev/cu.usbmodem2621 (Arduino Due (Native USB Port))

Open the Serial Monitor.  Set baud to 115200.

Note that if the text “( Native USB Port)” doesn’t show up in the lists, the board isn’t connected properly, or the Due wasn’t configured properly.

Connect via Octoprint

Based on this forum post, need this plugin in Octoprint to make it compatible with RRF:

https://github.com/markwal/OctoPrint-RepRapPro

Just browse the Octoprint plugin manager to this file to install:

https://github.com/markwal/OctoPrint-RepRapPro/archive/master.zip

To connect, press reset on the RADDS board, choose the serial port ‘/dev/ttyACM0’ and ‘Connect’.

If no serial port shows up after pressing reset on the RADDS, reload the Octoprint page.

See the section below for actually configuring Octoprint for printing with RRF.

To test the connection

Enter M115 into your serial console to report config status and know it’s actually working:  If the SD is in there with a /sys/config.g file (more info on that below), it should print something similar to what I have below, otherwise it’ll report ‘no config file’ (which still means things are working).

Send: M115
Recv: FIRMWARE_NAME: RepRapFirmware FIRMWARE_VERSION: 1.09r-dc42 ELECTRONICS: RADDS 1.5 DATE: 16/02/27

Then I plugged the RADDS back on top of the Due, and hooked up all the wires (more on hardware hookup below).


Macro Config

Macro files are the way you configure RRF.  They are .g text files that live in the /sys folder on the RADDS SD card, and allow RRF to reconfigure itself every time you turn it on:  No longer do you have to recompile the source to make an adjustment:  Just tweak the file on the card and reboot.

To get started, copy the content of /git/RepRapFirmware-RAADS/SD-Image/sys-CoreXY (presuming you’ure using a CoreXY machine like me) to your sd card root, and rename it to /sys

From there you can start editing the file:  Each time you plug it back into the RADDS board and reboot (and press reset after…) the config will be in play.

Good overview post on initial config:  http://blog.think3dprint3d.com/2015/02/reprapfirmware-config-files.html

Good overview of macros in general:  http://reprap.org/wiki/RepRap_Firmware_macros

The Wiki lists defaults for many Mcodes here.  I’ve experienced these defaults to in fact be incorrect in some instances:  If you plan on using a default, be sure to enter that Mcode into a serial monitor to see what it returns, and is valid.

Primary macros I use are as follows:

config.g

config.g is the main macro that is executed when the machine is powered on.  It’s akin to Configuration.h in Marlin & Repetier.  Below are the main steps I went through getting it configured, and describing what the M & G codes do… mainly for my own sanity as I learn this.

Set CoreXY Mode

Per http://reprap.org/wiki/Configuring_RepRapFirmware_for_a_CoreXY_printer, presuming your bot is CoreXY:

M667 S1 ;              set CoreXY mode

Setting max feed rates

Via M203

The wiki lists default values for M203 to be the values I list below.  However, before I set that, when I’d enter a M203, they’d actually come out to 6000 (mm/min) for XYZ:  Substantially slower than what I put in:  This was clipping my speeds going much past 100mm/sec.  Values below freed things up.

My Values:

M203 X25000 Y25000 Z25000 E8000 ;

Defining nozzle and bed thermistor

Via M305

I’m using a E3d-V6 thermistor for my Volcano hotend.

They state:

RepRapFirmware
Use the Beta value 4267K.​
It’s 100k Ohm

M305 P T B R L H X

  • P : Heater Number : Not to be confused with the ‘P’ (tool) value of M563. 0 = heated bed (RADDS bed), 1 = first extruder (RADDS H0). 2 = second extruder (RADDS H1), 3 = third extruder (RADDS H2).
  • T : Thermistor resistance at 25c
  • B : Beta Value
  • R : Series Resistor Value

When communicating with the RADDS, if you enter a M305 P0, it’ll print the current state.

My Values (just a generic 100k one for the bed), RADDS has a 4700 ohm inline resistor.

M305 P0 T100000 R4700       ; P0 = Heater 0 = The bed.  Not sure the 'beta' value for this.
M305 P1 T100000 R4700 B4267 ; P1 = Heater 1 = The extruder nozzle. Beta per the E3D docs.

Note, you’ll know these values are wrong if at room temp (25C / 77F) your control software (like Simplify 3D) doesn’t read 25(ish)c : I had originally set R1000, and it reported the resting temp to be 60c, very, very wrong.

Note I’m using the default PID settings for both nozzle and bed, and they seem to be working just fine.

Defining ‘Tools’

Via M563

This is where you setup your hotend(s).

M563 P D H

  • P : Specifies the ‘tool‘ number, 0 -> infinity.
    • D : The drive(s) used by the tool : 0, 2, 3 : D0 <-(zero) Is the first drive after the XYZ steppers, so presumably the extruder stepper.
    • H : The heater(s) used by the tool : 0, 1, 3 : 0 = Heated bed, 1 = first extruder heater.

My Values:

M563 P0 D0 H1 ; Tool (P) 0 : D0 = Extruder stepper 1. H1 = First extruder heater.

To select a tool in gcode, use T# to select it, T99 to deselect (needed?)

Defining axis direction and enable values

Via M569

M569 P S R X Y Z E

  • P : Specifics the ‘drive‘ number, not to be confused with the ‘P’ (tool) value of M563.  0=X, 1=Y, 2=Z, 3=E (right?).
  • S : Whether the drive should move forward. 1 = forward, 0 = backward.
  • R : Logic level.  0 is Default.  Set to 1 to reverse logic if you’re using RAPS128.

My Values:

M569 P0 S1 ;  X
M569 P1 S0 ;  Y - I needed to reverse this.
M569 P2 S1 ;  Z
M569 P3 S1 ;  E1

Set Endstop configuration

Via M574

M574 X Y Z S

  • X, Y, Z : The switch type for the axis : 0 = none, 1 = low (min) 2 = high (max).
  • S : Logic level : Defines whether the endstop input is ‘active high’ (S1, the default), or low (S0).

My Values:

M574 X1 Y1 Z1 S0

You can use M119 to report the status of your endstops.  Makes it convenient to test them while holding them on.   I had a super nasty bug where my X endstop wasn’t seated properly in the RADDS board, so it always reported off.

Defining steps per mm

via M92

For all steppers, X,Y,Z & E

My Values, copied from Repetier (with X&Y divided by 2, since Repetier doubles the XY steps for core-xy machines), since I’m using the same SD6128 drivers at 1/32 microstepping.

M92 X199.743 Y200.542 Z804.91
M92 E325

Fans

They were an amazing pain:  I have a hotend cooling fan, and a PLA cooling fan.  I also have a case cooling fan I never could get working via the below config, so I just hooked it up directly to my power-supply so it’s always on (Repetier was able to control it, so +1 for it).

This is what finally worked:

M106 P0 T60 H1 ; Hotend cooling fan: Enable to auto kick on at 60c (make it 'thermostatic'). 
M106 P1 H-1    ; Filament cooling fan: Must do H-1, or it'll turn on with P0 for some reason.
M106 P1 S0     ; Filament cooling fan: Must do, or it will go full blast on start :S

Comments:

  • If I didn’t declare P1 (filament cooler) non-thermostatic (H-1) it would turn on with P0 (hotend cooler).
  • If I didn’t set P1 (filament cooler) to a speed of 0, it would go full blast on machine start.
  • Still haven’t figured out how to hijack pin H2 to double as a case cooling fan (see complaint above).

Stuff to comment out / delete

From the default config.g:

  • All M540, M552, M553, and M554 (network) commands, not supported by RADDS.
  • M906 (motor current) commands : Not supported by RADDS.

homeall.g

This macro is called to during a ‘home all’  G28 operation

+ homex.g, homey.g, homez.g are just like it, but only on those individual axes.

Per http://reprap.org/wiki/Configuring_RepRapFirmware_for_a_CoreXY_printer

Make sure you set the G1 commands when moving the head some amount past your build volume, so they’ll be sure to hit the end-switches no matter what.  For example, my X platform width is 305mm.  So when homing:

G1 X-330 F3000 S1

I set it to go -330, just to make sure it hits.

Macro M & G code usage

Macros can live in the /sys folder, or in the /macros directory with any extension.

While in a macro, you can call another macro. Macros are searched in /sys directory and it is recommended to always specify explicitly the path.

M98 calls to other macros.

When are Macros called to?

  • config.g : Machine starting up
  • Pausing & Resuming:
    • resume.g :  M24 (Start/Resume SD Print)
    • pause.g :
      • M25 – (Pause SD print)  – From control panel\lcd\serial connection, not saved gcode.
      • M226 – (Pause SD print) – From gcode directly.
    • cancel.g : If a M25 is executed pausing a print, then you execute a M0, this is called to.
    • stop.g : Docs say this is called while M0 is executed, (or?) when a paused print is cancelled.  NOTE:  Mine doesn’t seem to execute at all though via a M0, paused or not.  I have no idea how to trigger this.
  • Homing:
    • homeall.g : G28 (Move to origin: Home)
    • homex.g, homey.g, homez.g : Called to for individual axes on G28.
    • bed.g G28 (Move to origin: Home) / G32 (Probe Z and calculate Z plane) – If using auto leveling
  • Tool selection:
    • tpre0.g : Before tool1 is selected
    • tpost0.g : After tool1 is selected
    • tfree0.g : When tool1 is freed

Wiring the hardware

I cover how to hook up hardware to the RADDS in depth in ‘this post‘, scroll down to the ‘Connecting the hardware’ section.

Some notes from this doc, for the RADDS board:

  • The minimum endstop headers are used for the endstops: X min, Y min, and Z min.
  • Thermistor position T4 is used for the heated bed.  This is the thermistor header farthest from the board’s corner.
  • Thermistor position T0 is used for the first extruder, T1 for the second, etc.
  • Controlling fans:
    • Fan0 with ‘M106 S# P0′.  Where S is 0-255 .  P0 is default, and can be omitted.  This if the hotend cooler.
    • Fan1 with ‘M106 S# P1′ :  This is the PLA  cooler on the hotend.

Configuring to print with RRF

If printing over SD, RRF expects your .gcode files to live in a /gcodes folder on the SD.

Print off the SD via MCodes & a serial connection

You can print via a serial connection by directly issuing M-codes:

M20                ; list sd card contents to see what's there
M23 myPrint.gcode  ; select the gcode to print by name
M24                ; start the print

Configuring Simplify 3D

  • In the ‘Firmware Configuration‘s’ FFF tab:
    • To tell it to control the second fan (PLA cooling fan) not the first fan (hotend cooler).
      • Set Fan Power: M106 S$ P1
      • Set Fan Off : M106 S0 P1
    • RRF uses M116 to stabilize temps (I’m told M190 & M109 are deprecated).
      • Stabilize Extruder Temp: M116
      • Stabilize Bed Temperature : M116
      • Note, you loose all serial communication while these are in use:  Including temp readings, so you’re a bit blind during that time if you have this setup to do so in your ‘start script’.
  • In the ‘Firmware Configuration‘s’ Communication tab:
    • Make sure that “Allow Command Buffering” is checked, and set the “Serial Cache Size” to 127 bytes:  When I had the default (63) set, I was unable to print over USB, it would lock the machine about half way though my ‘start script’, right after a G28 (home) operation.
    • Note, to print consecutively over USB, I have to reset the printer, and reconnect after each print, or it will lock up like mentioned above.  This is different behavior than Marlin/Repetier.
  • In the ‘Firmware Configuration’sMacros tab:
    • S3D’s default “Extrude/Retract” buttons in the Machine Control Panel don’t seem to behave correctly:  They want to extrude based on “absolute values”, not “relative” ones. The side effect is during a paused print, if you extrude 10mm, you can’t extrude any more unless you retract 10mm first.  To get around this, if you execute a M83 first, it’ll put the extruder in relative moves, and you can extrude as much as you want.
    • I make a Macro called “Relative Extruder Moves” and put a M83 in there.  I press that before I do any type of control panel extrusion.
  • Note you have to “Export” your firmware settings to get it to save.  The ‘save’ button doesn’t actually seem to save anything.
  • In a given Process:
    • Temperature Tab:
      • For all extruder and bed temp controllers, uncheck “Wait for temperature controller to stabilize before beginning build”.
        • You ask “Why?  This is a great feature”.  Indeed it is, and I agree.
        • However, while the temp stabilizes via M116, you’ll get no serial communication back from the board, making you both blind to what’s happening, and unable to communicate with it in any way, to (for example) stop it if needed.
        • You’ll need to pre-heat the machine and get it to temp before starting your print if you go this route.

Configuring Octoprint

  • As of this authoring, the main branch of OP isn’t designed to work well with the RADDS SD card:  Doesn’t recognize it properly, so you can’t print off of it.  You can print off the Octop’s SD via USB however.  I’m not a fan of printing over USB, so I didn’t like this option.
  • Thanks to work by Mark Walker while I dealing with all this, he updated a dev branch of OP to recognize the SD card, making it possible to print from it like any other firmware.  To get this dev branch, follow the directions below.  It worked for me without a hitch.  Thanks Mark!
  • In the Octoprint’s settings, under ‘features’:
    • Check ‘Enable SD Support’
    • Check ‘Always assume SD card is present’,
      • …or you won’t be able to see the SD card on the RADDS.
    • Once you’re on the dev branch (below), also check ‘Select SD files by relative path’ to be able to print off the SD correclty.
  • Also don’t forget to install this OP plugin:  https://github.com/markwal/OctoPrint-RepRapPro/archive/master.zip
  • Finally, once you’ve switched to the dev branch, do not update Octoprint: It will overwrite the update, and you’re back to square one.  Hopefully they’ll roll these updates into mainline at some point.

Switch Octopi to the dev branch

…that supports printing off the SD card on RRF \ RADDS:

This is a condensed / modified version of this Octoprint FAQ.  Like they explain, only use sudo on the FIRST COMMAND listed below, and nowhere else.

SSH into your pi.  Then:

sudo chown -R pi.pi ~/oprint ~/OctoPrint
cd ~/OctoPrint
git pull && git checkout dev/rrpFileOpened
~/oprint/bin/python setup.py clean
~/oprint/bin/python setup.py install
sudo service octoprint restart

When Octoprint restarts, you should see this version at the bottom of the web interface:

1.3.0.dev784+gf8c67fd (dev/rrpFileOpened branch)


Issues

Outstanding:

  • None

Resolved:

  • M190 (Heat bed and wait for target temp) & M109 (heat hotend and wait for target temp) cause machine to loose communication during heatup.
    • The commands tell the machine to ‘do nothing until target temp is reached’.  This includes any serial communication in RRF (compared to Marlin\Sailfish\Repetier that keep the serial communication lines open in my experience).  The side effect is the appearance that you’ve lost USB connection:  Communication will come back when target temp is reached, but in the meantime you’re blind.  I don’t like it.
    • I’m told that M190 & M109 are deprecated in RRF, and to use M116 instead:  While this command works, it still also hangs all communication in the process as well.
    • Solved:  Don’t use any of those Mcodes, and just heat everything up before hand manually. I don’t like this, but it works.
  • Endstops not being detected no matter what combo of values is entered into M574.
    • Solved : X-endstop wasn’t seating correctly in the RADDS.
  • PLA Cooler fan turns on automatically when using M563 to define the first tool.
    • Solved : Setting Fan0 to thermostatic (turn on when hotend reaches certain temp) it aut0-fixed this.  Weird.
  • PLA Cooler fan doesn’t respect PWM control:  It’s either 100% on, or off.
    • Solved:  Needed tricky config.g, see above.
  • Extruder doesn’t seem to be reading the correct temperature.
    • Solved:  Wrong inline-resistor value: had 1000, should be 4700 (what’s on the RADDS boar).
  • RADDS case cooling fan is hooked to H2 (hotend heater2) in Repetier successfully : How to configure that as a fan in RRF?  Still haven’t figured it out yet.
    • In the meantime I rewired them to mains so they kick on automatically when the machine is powered on.
  • The Due reset bug: Whenever I power on the Due\RADDS, I have to press reset to actually make it boot the firmware.  This happens in Repetier too.
  • RADDS LCD is not supported at this time, but the PanelDue is.  Plus, it’s a touchscreen.

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Building the C-Bot 3d Printer : Part 33 : Machining a mic6 aluminum removable build plate

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Overview

I’ve been using removable glass build plates for years on both my Makerbot Replicator 1, and my custom C-Bot:  I get double-thick glass cut at my local hardware store (Orchard Supply Hardware has had a great price on this), always thinking it was ‘totally flat’.  But is it really?  My C-Bot has a 12×12″ heated build platform.  When I go to level it with the glass, I get each of the four corners dialed in perfectly.  But the middle always sags slightly… even though it’s glass.  Double-thick glass.  But glass is actually somewhat plastic, and this sag has always bugged me.

Back in December I assembled my 1000mm X-Carve CNC, and it’s been so much fun cutting wood.  I knew it could do aluminum as well, but needed  a project.  And that’s what this post is all about:  Using my X-Carve to machine a new removable build plate out of .25″ mic6 aluminum for my 3d printer.  I am so happy with the results.

Sourcing the material

Before I started this, I had no idea what ‘mic6’ aluminum was.  It’s also referred to as ‘cast aluminum tooling plate’ or ‘ATP’, since mic6 appears to be a trademarked brand name.  Simplistically, it’s a standard for (among other things) a very flat aluminum plate, to .001″.  After reading a plethora of forms, and researching my local options, I settled on Midwest Steel And Aluminum’s “Cast Aluminum Tool & Jig Plate“, .25″ thick, 12×12”, which came to about $20, and the ground shipping another $20.  I could have bought it locally for $45 + tax (ugh).

A note on the order:  The plate was packaged in one layer of cardboard, that was it.  It appeared to have been dropped several times in-transit, 3 of the 4 corners were blunted, and there was an small indentation in the middle of plate itself.  If I was using this for something really precision I would have returned it.  Just a note to tell them to ship it better if you go this route.

Once it showed up, time to make some cuts!

Initial cuts

When I first got the plate I knew I had to notch a section out of each corner, since the heads of the bolts that hold the MakerFarm heated build platform stick up about 1/8″ish from it:  I didn’t want the plate resting on the bolt-heads, so I need to make little pockets for each.  Before I even considered my X-Carve CNC, I figured I could use my drill-press to pocket these.  Long story short:  It did not work well, and made a mess of the corners.  Based on that frustration I went down the ‘how about I use that dormant CNC right next to the drill press…” road.

For all below cuts, I used the same 1/8″ 2-flue upcut carbide endmill.

Since these cuts were so simple, I used Inventable’s Easel: I designed a circle with a diameter of .4″ across, .175″ deep, and used that to pocket each of the four corners already mangled by my drill press.  I used the default ‘aluminum’ Easel setting (5 ipm, .003″ doc, DeWalt on speed 1) with the first pocket (which took about 20 minutes), then started cranking it up: By the final pocket I had it running at 20 ipm at .01″ doc, with the DeWalt on speed 2, taking about 5 minutes..  It did great, and the bit was cool to the touch after the cuts.  When all four pockets were complete, it fit right on the bed with no collision with the bolt-heads:

cornerPocketAll the rough stuff to the right of the bolt-head was the abuse by the drill-press.

I have four bulldog clips that hold the plate on, one on the middle of each side.  The issue is even though I’ve bent them down to move them out of the way, parts of them still stick up slightly, and on a large print the nozzle could collide with them.  So going back to Easel, I designed a new rectangular pocket that would keep the bulldogs out of the way of the toolhead.  These were 2.25″ x .3″, cut .075″ deep.  I positioned them in the center of the left\right sides of the build plate, but had to offset them on the front\back based on my leadscrew config.

An in-process cut:

bottomPocketCut

And all four final cuts:

bottomPockets

Installed on the printer:  No more clearance problems with the bulldogs! :)

topBulldog

Prepping the plate

I use a highly secret (50% wood-glue, 50% water) slurry on my build plate to get PLA to stick.  But the mic6 is so smooth, I first scoured it with steel wool for several minutes to give the glue something to bite into.

Note for the future:  First, use something like lacquer thinner\acetone\mineral spirits to clean the plate of any oils:  Quite to my surprise, after many minutes of scrubbing, I could clearly see my handprint on it.  The oils deposited from my hand actually protected it from the steel wool.  So I went back and liberally scrubbed it with lacquer-thinner soaked rag, then went back to the steel-wool treatment again:  No more handprint.  Be sure to wipe it down with lacquer thinner after the steel wool too:  The wool actually leaves quite a bit of itself deposited into the aluminum.

After the plate was scrubbed, cleaned, and glue-slurry applied, I did some test prints.  And while the flatness was super awesome, I realized something very quickly:  The slicer said the bed heated up waaaay faster than it actually did:  For big prints in PLA, I’ll heat the bed up to 60c.

It dawned on me that the thermistor that does the temp reading is taped to the bottom of the MakerFarm heated build platform, while the thing being printed is sitting above it on .25″ of aluminum… that is taking much longer to heat up.

After brainstorming, I came up with the idea of cutting a groove into the bottom of the plate, that I could tape the thermistor into:  It should then be reading the temp from the removable plate itself, providing a much more accurate temperature.  This means I’ll also need to snip the leads running to the thermistor and install a barrel-jack into the mix to allow for the plate to be removed, since there’s now a sensor taped to it.

Secondary cut

Going back to Easel, I designed a .5″ wide groove cut .0312″ deep that I could recess the tape into, then another smaller groove .2″ across and .1″ deep to run the wires to the thermistor.

Here it is mid-cut:

bottomGrooveCut

Cut gotchas:

  • Easel has (based on what I’ve experienced) no idea of conventional cuts (bit spinning in the direction of travel) and climb cuts (bit spinning opposite direction of travel).  From what I’ve read, climb cuts can provide better finish, but only on ‘professional\beefy’ machines:  not the X-Carve.  Conventional cuts fare much better on the X-Carve.  This (as I found out) can cause dangerous problems.
  • When the top cut started, it was all conventional cuts, and cut fine.  But when the next layer started, and for every layer down, it was climb cuts.  Because of that, I noticed a lot of bit defection, chattering, and even gouging.  To avoid catastrophe, I had to manually monitor the cut, and really crank up the spindle speed as needed to compensate.
  • Note that MeshCAM gives you the option in the rough-cut to do either conventional or climb cut:  For future aluminum projects I’ll be using it for sure.

To help with heat transfer (that is only a theory of mine) and to prevent any sort of plate-slip (which is legit), I shoot the bottom of the plate with rubberized undercoating.  I then snipped my thermistor line, soldered barrel-jacks onto either side of it, then taped it into the groove on the bottom of the plate:

bottomFinal

Putting it back onto the HPB, I reconnected the barrel-jacks:

underWiring

Final thoughts

It works, great.

topFinal

When the HPB heats up, and it finally gets to temp…. it really feels like the top\bottom are the same temp.  And I can level each of the four corners, and the middle is the exact same distance as the rest of them from the toolhead.

Super rewarding project with one machine improving another.


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