Rolling your own Marlin build

So I wanted to have a crack at rolling my own firmware build for my Ender 3 V2.  Marlin is pretty awesome - and setup in a way that makes it pretty user friendly.  I would start with this video from Teaching Tech.  He goes through how to build your own firmware - which I 100% used as a base.  I did a few things slightly differently and probably will continue to tweak as I go.  If you just use his video and follow it you will absolutely end up with a useable firmware.  This post is as much for me as anyone else that might stumble across it - on what options I used.  

So start by making sure you have git and Visual Studio Code installed and up to date.  Open code and install the PlatformIO IDE extension:

I then checked out the Marlin code and switched to the bugfix-2.0.x branch that Teaching Tech suggests in his video:

git clone https://github.com/MarlinFirmware/Marlin.git
git checkout bugfix-2.0.x

You could skip this and just download the zip file of source from GitHub like the video - I just tend to default to using git.  I then downloaded the configuration zip that is mentioned in the video (you can find it in the /config/readme.md) and has a bunch of configs for different printers - I used the bottom one as that matches the branch I am using:

I then extracted the zip and jumped to:

\Configurations-bugfix-2.0.x\config\examples\Creality\Ender-3 V2

I copied the contents of this directory to Marlin directory, inside the Marlin folder when I checked the code out.  Overwrite any files that already exist.

At this point I flicked back to code and opened the folder I had just created when checking out Marlin.  There are a couple of config options you need to edit as suggested in the video, the three files and the options I changes are:

\Platformio.ini

Changed default_envs to be this to match my Ender 3 V2 with the 4.2.2 board:

default_envs = STM32F103RET6_creality

Marlin\src\Configuration.h

Find the following lines and uncomment to enable my BLTouch:

#define BLTOUCH

#define AUTO_BED_LEVELING_BILINEAR

#define Z_SAFE_HOMING

Find the following line and uncomment and change the offsets to match those of the BLTouch mount I used off thingiverse (in the description on that page):

#define NOZZLE_TO_PROBE_OFFSET { -42, -10, 0 }

Marlin\src\Configuration_adv.h

Find the following line and uncomment:

#define BABYSTEP_ZPROBE_OFFSET 

You are now ready to try and build.  Click the little "tick" in the bottom bar in code and the build will kick off.  The very first one you do will take a couple of minutes while it downloads a few bits - but subsequent builds should be 30 seconds or so.  

The firmware file created will be in:

\.pio\build\STM32F103RET6_creality

You want the firmware-[date]-[time].bin that matches the timestamp of when you just did the build.  Copy this file over to an empty micro SD card and whack it in the printer.  Turn it on, and it will update and when finished jump to the menu.  You can check the version by going to Control and then Info down the bottom:

At this point I also updated the LCD firmware too - since I could (I'm not actually sure how to check it's version - so just did it anyways).  The video is a better guide here and I did exactly as suggested - copied the DWIN_SET folder from the config examples directory over to an empty SD card, took the LCD apart and put it in the SD slot and turned the printer on.

Any nothing happened - it just booted up like normal. 

After a minute trying a few things I took another look at the SD card and it was formatted FAT and not FAT32.  I re-formatted the card FAT32, copied the DWIN_SET folder back over and tried again and it worked first go.

At this point I had a printer ready to setup.  I reset all settings as suggested in the video by going to Control and then Restore Defaults, and then hit Store Settings to save a fresh copy.  I then tried an auto home and while X and Y worked fine - Z with the BLTouch did not.

Turns out the way the firmware is configured by default and the way Teaching Tech does it in his video too meant I needed to change my BLTouch connections on the control board to put the Z Stop into the ZStop sensor header on the board (previously I had it all in the dedicated BLTouch header).  The black/white pair below:

This makes sense - to leave it all in the dedicated BLTouch header I'd need to change the pin setup in the config files for the Z Stop.  Creality must do this in their build config as using their stock BLTouch enabled firmware only worked with the BLTouch wired to the header as mine was initially.  I switched this wiring over and the ZStop / BLTouch worked as expected.  

I did an autohome and then a bed level.  I then set the Z offset as discussed in the last post about the BLTouch.  It was slightly different this time (-1.97 vs -1.99) but I did have to move the printer around a bit to get at the control board to change the wiring.

I now have a printer that prints exactly as it did before... :)  But it is running firmware I built - that I can continue to tweak as I learn!

Bed levelling upgrades

 So after getting the filament sorted - the next thing to look at was bed levelling.  I was trying to get a consistent first layer - and unsurprisingly Teaching Tech had a video and a whole website devoted to bed levelling!  He goes through it in the video but his site generates a gcode file that will print 5 squares by default to help you see if your first layers will go down consistently in each part of the bed.  

This alone helped me quite a lot - prior to this I was just doing the manual bed level and kicking off a print.  What I was finding though was that I couldn't quite get it perfect - and it was changing a little each day.  I'd get it pretty good, do a bunch of prints that were ok and then come back a day or two later and need to re-level again.  

So I've done my first two upgrades!  The first was a spring and levelling nut upgrade kit.  This was super easy to put in - and very much holds the level that is set longer than the stock springs/wheels did for me at least:

Once this was in I levelled again and tried the first layer gcode from Teaching Tech's site with pretty awesome results:

The bed itself is not perfectly flat as covered in the video - plus I really like the idea of being able to programmatically auto bed level - so I bought a BLTouch too :)

This one is a slightly more detailed install - I printed a mount off thingiverse and got to work installing the BLTouch.  I installed the mount, mounted the BLTouch and ran the extension cable to the control box underneath using the existing cable sleeve.  It's worth noting you need to order an extension cable if you buy a BLTouch for an Ender3 V2 - the default cable length is way too short.  I cut the 2m cable and re-terminated it to the right length - about 1.5m would be perfect.  You could easily just loop that last bit up though if you don't want to re-terminate the cable.  The other cool bit is that the the new control board in the Ender 3 V2 has a dedicated port for a BLTouch - no adapter board on the display port required so it's plug and play.  

All guides recommend you disconnect the Z axis stop when you add a BLTouch as it becomes the Z stop.  I didn't initially and saw why people suggest this needed to be done - the Z stop switch did occasionally trigger and the BLTouch/printer can't handle it and bugs out.  So I have now unplugged my Z stop switch :)  The last bit required to get going with the BLTouch is a Marlin build with it enabled.  

This is another rabbit hole that I am currently exploring - custom firmware.  That's a future post though.  For the moment Creality do produce a firmware build with the BLTouch enabled.  Going to the Creality site, the downloads section and then selecting the Ender 3 V2 gives you a bunch of files that are a. little confusing on first glance.  I actually flashed the wrong firmware because I didn't understand this and thought I was just grabbing the latest firmware - not realising it was for a different board revision.  After flashing this wrong firmware the printer would just boot to a blank screen.  

So as of writing the filenames are something like:

4.2.2 Ender-3 v2 Marlin2.0.1 BLtouchV1.1.1without adapter board firmware.rar

The first set of numbers are the board revision (I have a 4.2.2 - and not a 4.2.7 as I initially downloaded).  As mentioned this board has a dedicated BLTouch port too - no adapter board required - which is also mentioned in the filenames.  So go for the one that says without adapter board.  

Luckily nothing was bricked - I just had to grab the right firmware (filename above) and put it on an empty micro sd card and name it something new (the Ender bootloader needs a unique filename to flash a new firmware).  This brought the printer back to life with a new "Level" option on the main menu and the BLTouch initialising when you turn the printer on:

So at this point I hit the level option on the menu - and I have to say it's pretty awesome watching your printer setting a level mesh.  This failed the first couple of times thanks to the Z Stop switch still being connected and triggering once or twice as mentioned above.  Unplugging it fixed that.  

The last part is setting the Z Offset.  This is the difference between where the BLTouch triggers and your nozzle/hot end.  Again Teaching Tech has an awesome video explaining this - but he uses custom firmware with a Z Offset tool (which I don't have just yet).  I just used the auto home option (which will set the printer up to where it thinks it at zero including any z offset) and then adjusted the z offset there to get it to the right height for my setup (-1.99 for me) with a bit of paper like manual bed levelling.  

A word of warning - you are supposed to be able to live adjust the Z offset during a print - and I 100% have the option in the stock firmware I am running at the moment and tried it but the printer didn't seem to like it too much.  It went down way to much when I was adjusting it just 0.01 at a time killing the print.  This was confirmed by stopping the printer and trying the exact same setting before starting a print which would work.  So I stuck to setting the Z offset prior to any prints.

The end result is some super stellar first layers - they go down smooth and consistent across the bed with the perfect amount of "squish"!

Filament matters

So one of the first things friends who already had printers told me was don't skimp on the filament - which is exactly what I did.  When I ordered the printer online I also ordered the cheapest white filament I could find online.  

I did my first 3 or 4 prints with the sample filament that came with the printer and it worked pretty well with the default bed and nozzle temps.  When it ran out I swapped it out with the filament I had bought and low and behold - it was pretty crappy.  Lots of stringing and the first layers weren't great.  I changed the temps around a bit and it got a little better - but still wasn't great.  So after chatting to the same friends and telling them they were right they recommended 3dFillies.  

They shipped really quickly and came in individual resealable bags with moisture absorbing sachets.  I've done all my printing with their filament since (I got a roll of white and and a roll of black PLA+) and it's awesome.  I printed  a tool mount and filament guide in black for the printer and they both turned out great (comparison of the tool mount with the cheaper PLA I got first):

I've been told their silk filament is awesome too - so I'll try some of that at some point in the future too.

Getting started with 3d printing!

It's a bit of a running joke that I have been waiting for my 3d printer since 2017 - this one.  It's very obviously never going to show up - and even if it did it would be so out of date now 4 years after design.  So I finally got through the five stages of grief this Christmas and got an Ender 3 V2!

This is the latest revision of the popular Creality Ender 3 series - with a new 32 bit board with a bunch more storage and quiet motor drivers stock.  It also has an updated colour LCD, power supply moved down the bottom instead of on the side and a few other little bits.  I ordered the printer from an Australian reseller and it showed up in a few days.

The packaging is awesome - all very neat and tight:

The printer comes partially assembled - following the included instructions I had the printer together and powered up in about an hour - in between making my kids breakfast:

At this point I had a crack at bed levelling manually with a bit of paper.  Simple as doing an "autohome", disabling steppers in the menu and then moving the head to the four corners of the bed manually.  In each corner you need to slide the bit of paper between the bed and the head adjusting the bed up and down using the levelling wheels below the bed so that the paper just catches.  I did a couple of rounds of this and was then keen to try a print with the included filament as is.  The micro sd card comes with two gcode files - a cat and a dog.  I printed both:

For first prints "out of the box" I was pretty impressed.  I know some have had varied results out of the box like this but mine were pretty awesome.

At this point I realised I probably needed to watch a couple of videos and read a few blogs about what the heck I was doing.  By far the best resource I was recommended so far is Teching Tech on YouTube.  He has a bunch of awesome videos.  This video is a great primer for anyone who just bought their 3d printer - I should have watched it and a few others first but where's the fun in that.  

At this point I installed Ultimaker Cura and created a profile for my Ender 3 V2 (as there isn't one in the Cura just yet) using this page as a guide.  You take the base Ender 3 and change a few settings for the Ender 3 V2.  I left the print settings alone for the moment and have just been using the default print setting profiles in Cura (all on Standard Quality to start with).  

Overall I am stoked with how good this thing is out of the box for a 3d printer n00b like me.  It's been printing most days since I got it - to balance printing with the huge list of possible upgrades and learning I'm doing!