I'd like to have a shutdown switch on my Pi's, and maybe one more switch could be handy for some other future use like pausing a print using an Octoprint plugin.  Since I am gonna standardize the Pi mounts (they will all use my latching mount) and cases for my various Pi's (the cases will be Sneak's Modular Snap Together Raspberry Pi Cases), I decided to see if a switch or two would fit in the OLED+Fan cover module.  I'm not sure if this will work, and the parts are really small so it may not be practical, but I'm trying it anyway.  I have a bunch of mini tactile switches from an assortment I bought some time ago to fix something, and they have been handy a few times since.  The downside is they are weird little switches and not easy to get, they are also tiny.  I originally thought I would try a 6x6mm tactile switch but found it was way too tight a fit.  So I found a smaller 6x3.5x5mm switch that looks like a better fit.  So I modeled the switch, and a clip to hold it, as well as a button to use since the button on the switch is way too small to be useful by itself.  I'm planning to print some test models to verify the button clip will work, and will update this post with how it works out. 

Update 1/15/2022 - It looks like the button module will work.  I still need to test some tweaks to the design to help things fit better but I'm pretty happy with the prototype module.  I had to rotate it 180° due to interference between the switches and the dupont connectors for the pins being used for the OLED and switches.  I also had a dead OLED display (but fortunately bought two and the other worked).  I would also highly recommend using ribbon cable for wiring the OLED and buttons since it is very tight.  I also connected all the grounds at the OLED so I could run one ground back to the connector (and have 2 fewer wires to run). 

The switches control shutdown (left) and pause (right).  The shutdown uses GPIO27 and the pause uses GPIO17.

To enable the shutdown button I used this guide:
https://raspberrypi.stackexchange.com/questions/77905/raspberry-pi-3-model-b-dtoverlay-gpio-shutdown

and just added this line to /boot/config.txt:

dtoverlay=gpio-shutdown,gpio_pin=27

To enable the pause, I used the Physical Button plugin for Octoprint. 

The OLED was set up using Sneaks Guide which is linked from his post on Prusa here. 

Once the fixes are made and tested, I will post this as a remix on Prusa.

Update 1/16/2022 - Really liking the new case, it looks very cool with the LED fan and OLED display.  But there is a part of me that is bugged by the wires that were not really crammed in the case, but I feel I could have done a better job.  I was also thinking that due to one of the buttons being on top of the IO header, I could possibly get the module flipped the "right" way if I could make the case taller.  The problem was how tall?  That turned out to be 12mm taller, to allow the top module with the buttons to sit over the IO header, with a Dupont connector on it.  This is only necessary due to the way I fit the buttons on the remixed module (on the sides of the display).  With the stock fan+OLED module there is no issue with the depth of the case. 

I did a hack of the case to stretch it out, and am printing a test model now.  I'm also testing a less aggressive fuzzy skin, and for fun I sliced up a fuzzy skin texture which has a Pi Logo inset (but I'm not printing that one at this time).

The button clips and some other things were tested and work well, I think this is almost ready to go, but I have yet to test print the whole thing.

I recently saw a post on Reddit where /u/ncarson9 make a card deck with fuzzy skin, but inset a logo into it which was printed normally.  The effect was really cool and they also posted their settings which I'm gonna try and use for a custom fuzzy skin texture on Sneaks new Pi4 Case.  This required a bit of modeling to get a shell which the fuzzy skin is applied to, and then merged with the original case top model, so it's not a simple process unfortunately.  I have not printed it yet but the preview looks promising.

I'm planning to use the same settings as provided in the linked Reddit thread by /u/ncarson9 @ Reddit:

Fuzzy Skin
Thickness 0.1    
Density 1.25    
Skin Point Distance 0.2   
Layer Height 0.2mm

Additionally, I set the z-seam location to "Random" on the inset part for the fuzzy skin texture.  The rest of the model was printed normally and I left the z-seam to "user specified" which was placed on the back with sharpest corner set.

Update 1/9/2022 - The print did not turn out as well as I had hoped, but it did sort'a work.  It had some areas that appeared to be fuzzy skin which were printed where it should have been printed normally.  Other areas had an exaggerated fuzzy skin compared to later printed areas (which is why I suspect the filament may be wet)  I downloaded the gcode and previewed it in Cura and it looked OK, so I don't know what occurred there.  I'm gonna try again though, and have run the PLA through the dehydrator just in case it's wet, and also will slow the print down to 20mm/s (it was printed at 36mm/s).  It may also be related to jerk possibly but I am not sure I will change that setting yet.

Update 1/10/2022 - My 2nd attempt at this was less of a failure (I think the PLA was a bit wet the first time).  However the effect I ended up with does not look great.  It may be the PLA, or it may be that I need to use more aggressive settings for fuzzy skin, or some problem with my printer (Ender3 with Titan Areo and custom cooler parts).

There was also the same problem of a rough texture in an are that should have been sliced normally (see below).  I'm not gonna give up on this idea though, since it could be really handy on some prints, but I think I should not have jumped in and tried it on a model I actually need to get done.  I'm gonna keep testing but will try it on some test models (like a simple cube with different fuzzy skin settings on each side).  I know that people get some really great results with fuzzy skin, so this is either a problem with my printer, filament or settings. 

I'm gonna try testing fuzzy skin settings further on my CR10S Pro next time, with a different filament (but it is tied up with lithophane projects for a while).  I think I will just print one more case top without any fuzzy skin to make sure the rough area I saw on two fuzzy skin tests is not going to show up regardless (in case it has to do with cooling or something).  That's it for now though.

Well I lied, that's not it for now.  I couldn't just let this be, so I made a 30x30x10mm test cube to try four different settings of fuzzy skin (one per wall).  I'm also running a different PLA to see if that will help with the result.  These are all using the same "density" value but I may change that next.

Update 1/13/2022 - The test cube was helpful to sort out the best looking settings which are very close to the ones from Reddit (and these are probably gonna be specific to the material and maybe the printer).  I'm using these currently:

Fuzzy Skin
Thickness 0.2    
Density 1.5    
Skin Point Distance 0.3  
Layer Height 0.2mm    

But I'm still not happy with the prints using the fuzzy skin.  I noticed again after three tests of the top of the case, that the fuzzy skin runs over the edge on the front left side (nearest the ports).  Whether this has to do with orientation or not, I see a bit of it on all the sides.  There is also some blobbing at the corners, which could be flow or retraction related.  It's not bad looking overall though, and I think it may work if I can somehow get the settings pinned down.

One To try something else, I decided to change the overlay model I'm using to apply the fuzzy skin texture. I have raised it 0.1mm off the surface of the rest of the model, in case the issue was with the slicer deciding which skin to print (fuzzy or normal), and I have also changed the slicer settings to reduce jerk and acceleration (Jerk = 4.0 and acceleration = 300mm^2/s).  I'm also using the latest version of Cura (4.13.0) which was just released (however I did not see anything about improvements to fuzzy skin so it may not matter).  That case top (4th) is on the printer now, and if it does not make a difference, I may put the idea of using fuzzy skin aside for a while, until I have more time to work on it. 

Update 1/13/2022 (#2) - Well it did the same thing on the left front of the case as is shown in the above pics, overran the area where fuzzy skin should have been applied.  I have tried two printers, Cura 4.12.1 and 4.13.1, and have changed the model, calibrated flow, and tried various settings including speed, acceleration and jerk with no effect, so I think I'm calling it quits for now on this particular way to use Fuzzy Skin.  It's probably some ringing which I don't normally see but the fuzzy skin is bringing out, so I will need to look into that before I continue with this idea.

Update 1/14/2022 - Well I couldn't leave this alone, its just too cool a feature not to try one more thing.  I re-read the thread on reddit since the results in that post are really good.  I noticed this time that a "cutting mesh" was used.  I have been trying to simply overlay one mesh on the model and have not tried the cutting mesh (have never used it).  I just re-sliced using the cutting mesh and it looks a bit different so I think this one may be a winner.  From the pic below, it looks like the fuzzy skin is almost being treated like another part with a separate wall being printed for the normal areas, that should eliminate the possibility of ringing where the fuzzy skin interfaces with an area or normal skin.  I'm running one more test print and will know in 6 hours lol.

Update 1/15/2022 - the first test using the cutting mesh was not great since I forgot to revert some settings, but I re-printed it using my normal settings and it looks better.  It's still something I need to experiment with, but so far these settings seem like a decent start to use with the "Cutting Mesh".  The cutting mesh is the part used to intersect the model, in areas where other settings (like fuzzy skin) can be applied.

CUTTING MESH settings for fuzzy skin:

Optimize Wall Printing Order (YES)
Z-Seam Alignment (Random)
Flow (decreased by 1%)
Print Speed (same)
Fuzzy Skin (YES)
Fuzzy Skin Outside Only (YES)
Fuzzy Skin Thickness (0.2mm)
Fuzzy Skin Density (1.5)
Fuzzy Skin Point Distance (0.3mm)

This leaves a bumpy fuzzy skin texture which is what I was going for, but I did end up knocking it down a bit with some sandpaper since fuzzy skin also can leave some rough spots which feel uncomfortable when handing the printed model.  A light sanding knocks those down and makes it look a bit better too I think.

Something I noticed when previewing the slicer was that at one point the fuzzy skin was printing before the normal skin areas of the model, but after some change (I think it may have been adding "Optomize Wall Printing Order (YES)" to the cutting mesh, it sliced with the normal wall printed first, and then the fuzzy skin.  I think printing the normal wall first is best since it will avoid dragging excess material deposited from the fuzzy skin across the normal areas.

I had to make some changes to the design to lower the camera, since it was not catching the action too well where it was before.  My wring is still a mess but I'm working on some cable management.  

It's not much to look at now, but you should see it in action :D  It looks like the endoscope camera will work pretty well, and I have it set up with the MultiCam Plugin for Octopring (which allows toggling between cameras using the buttons on the "control" tab within Octoprint):

This is not really a guide, but just some observations on how to get this working (multiple cameras in Octoprint).

To do this, several things were required.  First a working Octoprint install on a Rpi (4 is preferred due to the load from the extra cameras).  Also a good power supply or a powered USB hub that is compatible with the Pi.  An SSH terminal app on a PC such as Putty (https://www.microsoft.com/en-us/p/putty-unofficial/9n8pdn6ks0f8?activetab=pivot:overviewtab)

I first had to get the mpeg stream to work from the new endoscope camera, and to do that I follwed this guide:

https://community.octoprint.org/t/setting-up-multiple-webcams-in-octopi-the-right-way/32669

Some basics on this process first though.  To access the pi, the Putty program will be used, just open it and put the IP of the Pi in (leave the port as 22 - which is for ssh).  Then log into the pi with username "pi" and the default password is "Raspberry" but please change it to something else using the "passwd" command (follow the prompts and don't loose the password).  Note that the password here will not be the same as the one used for Octoprint, they are different so changing one does not affect the other.

Next, I just followed the guide linked above, but as usual I ran into a problem (s).  When I set up the files /boot/octopi.txt and /boot/octopi.conf.d/webcam2.txt for the webcams, I made some typo's and failed to close some quotes or left double quotes.  That jammed everything up so if you find things don't work, look over those really closely.  I included screencaps of the working files below for reference (these were after fixing the typos):

This is covered in the guide, but if you need to see if your USB camera is detected you can use "lsusb", and you can find the "long name" of the USB cameras using "ls  /dev/v4l/by-id/".  Below are screencaps of what mine look like (you can see I have a Logitech C525 and the Endoscope is the "Sunplus" device:

If there are problems with things not working, checking in the webcamd log can point the way to what happened (more is a command to show file's contents on the command line):

 more /var/log/webcamd.log

Note that this log will keep growing every time the webcamd process is started so you need to go to the bottom to find the logs since the last re-start of the process.  They will start with "Starting up webcamDaemon..." and end with "Goodbye...".

As an example, I had some syntax errors (missing ") in my config files.  Look for things like this in the /var/log/webcamd.log (don't forget to scroll down to the bottom for the latest logs):

Additionally, if you see no syntax errors and it looks like it is not using your desired resolution but 640x480 instead, you can run this to see if the resolution is supported:

v4l2-ctl --list-formats-ext

If you make changes to the config files, then you need to restart the webcamd service every time (using "sudo service webcamd restart"), for the changes to take effect.

When both cameras are working the /var/log/webcamd.log will look like this:

Note that the notice that ":USB device was set in options and found in devices, start MJPG-streamer with the configured USB video device: /dev/video2" was not a problem, the above was a working example for both cameras, and I was able to stream using the endoscope camera using "http://192.168.0.22:8081/?action=stream".

Now that was working, I thought I would be set and could just put "http://192.168.0.22:8081/?action=stream" in the URL field for the Multicam plugin and it would be smooth sailing... Haha, few things ever work like that for me.

Even so, I tried setting the second (endoscope) camera up with "http://192.168.0.22:8081/?action=stream" as the URL, and it failed, even though I can open http://192.168.0.22:8081/?action=stream  in a browser and see the stream.

I realized at that point that I needed to set up the Haproxy according to the last part of the guide here (https://community.octoprint.org/t/setting-up-multiple-webcams-in-octopi-the-right-way/32669), so that's what I did, and it now works as it should (I can use the Multicam plugin to toggle between the cameras).  Below is my current working Multicam config:

One thing to keep in mind is that the multicam plugin does not show multiple cameras on one screen within the Octoprint UI, it only provides buttons to toggle which camera is used.  It can therefore be handy to just open another browser and stream the other camera (using http://192.168.0.22:8081/?action=stream for example - with your Pi's IP). 

I also noticed a bonus - the Multicam plugin also added a button for each camera in Cura (I did not have to configure this):

This is about the coolest upgrade to my printer, aside from the touch probe.  It's amazing to see how the first layer goes down and be able to make adjustments to it on the fly.

UPDATE 1/7/2022 - The design for the endoscope and BL-Touch mount is posted here:

https://www.thingiverse.com/thing:5191359

The Hydra Remix I made for my CR10S Pro has been working great, I should have done this earlier, but I could have done without the unrelated bed warping.  I'm still needing to work on wire management though and since I recently bought a USB endoscope camera, which is pretty much plug and play with the Raspberry Pi (I had to set camera=auto in Octoprint.txt), I decided to make a mount for it.  The camera quality is decent in testing, and the USB plug is a bit hard to get in and out, but it has a brightness control and should do the job.  This one has a rather stiff wire, which I'm not sure will be a positive or negative until I put it to use.

The mount I have designed will replace the fan guard / BL-Touch mount on my Hydra Remix.  The design will have a screw lock to secure the camera which is aimed at the nozzle on my MicroSwiss hot end.  I'm also trying to add some wire management to the remix (on the BMG mount).  Still a work in progress, but I will post it up if it works.

I saw Sneak's (@ Thingiverse) new modular Raspberry Pi case on Reddit a few days ago, and it looks great.  He posted it to Thingiverse here (those pictures are not renders by the way).  As soon as my printers are free from another project I plan to print one.  But in the meantime, since I have been using my Raspberry Pi Latching Base (which is also a remix using another great snap fit case from Malolo @ Thingiverse), I decided to make a latching base for Sneaks' case as well.  The model is done, but after finishing it, I thought that I may be able to make it compatible with my earlier latching base design for Malolo's case (which is 2mm narrower).  So I'm gonna try that and see how it looks before deciding which way to go with it.  I would really like to have a universal mount for all my Pi cases rather than one for each.  For now, here are some pics of the progress:

Update 1/6/2022 - Its tested and posted here:

www.thingiverse.com/thing:5188648

I couldn't decide earlier if I wanted to use a plain cover or the fan cover, but the LED fans won me over, so I have some 40x40x10 fans on order.  I will be printing the fan insert soon, and will post some updated pics.  I also did not like the way the overhangs turned out on the base so I will be printing that again (cooler and slower).

I just updated the design with the final versions of the models for my Remix of BoothyBoothy's Hydra Fan Duct System.  My remix is for the CR10S Pro and includes an adjustable BL-Touch style probe mount, which I may also post separately.

www.thingiverse.com/thing:4640040

I posted earlier about upgrading to a spring steel magnetic build plate on my CR10S Pro.  Due to the way this printer is set up with a thick aluminum build plate held on by clips, I had to choose whether to just remove the plate and slap the magentic sticker on the bed which is more of a sub-bed, or somehow use the aluminum plate. 

I decided to keep the plate and instead of holding it with clips, I used screws by drilling four holes through the plate and countersinking them.  I still think that method will work, but unfortunately when I set my bed up the holes were probably too tight and so heating the bed likely warped it as it bucked up in the middle, that is my suspicion at least.  I didn't  immediately make the connection since at the time I also had an inductive probe and thought there was some trouble with the combination of inductive probe and magnetic bed, however the mesh with the inductive probe was similar to the mesh with the 3D Touch probe I later installed (though the 3D Touch probe seems quicker to probe the bed).

My fix to stop the problem from getting worse was first to open the mounting holes I made in the plate, and second to only tighten the screws holding the bed snug, and not to torque them too much.  The bed still feels solid and I don't expect anything to shift.  I think these changes will allow the plate to expand and contract without warping further.  That is just a theory though, and I may have warped the plate some other way, though I did not notice anything when working on it and it was always fully supported when drilling the holes (I used a backer of press board). 

In any case my bed is now warped and I'm not feeling like spending 60 bucks to swap it.  I decided to try adding some Kapton style tape to the low spots, after getting the wheels set as best as they could be.  This is what I had to start with, there is a high bulge right across the center which is parallel to the x-axis:

Widening the screw holes did not help much since I suspect the damage was already done. 

I probably could have flipped the plate and tried un-warping it but who knows what I would end up with so I tried adding tape to the low spots.  The tape was added in horizontal strips along X-axis and I just added more to bring up the low spots.  I re-adjusted the wheels as well, a couple times in this process to try and tune things but the adjustments were minor.  I found that I needed quite a bit of tape at the back of the bed, and finally gave up there since it was getting out of hand and I want to see if things will settle in at all.

Seems like there is never a simple upgrade on a 3D printer for me.  When my extruder arm busted and I could not find my Tinymachines updated part to replace it with, I got all excited about installing a BMG clone on my as then untested Hydra Remix for the CR10S Pro.  Well it's tested now, and will be updated with some fixes though nothing too major that I couldn't make some changes on the fly to the prototype I tested (and am still using).  But what sort'a messed me up was that after I installed the new magnetic bed, it seemed cool with the old setup and ABL seemed to be working OK, but when rebuilt the hot end it got all nutty and appeared that there may be some issue with the inductive sensor interacting with the magnet (which I sort'a expected though was suprised after the initial ABL did not show it.  In any case, I had some old 3D touch probes around (and one bad one which is of course the first one I picked), so "upgraded" the inductive sensor to a 3D Touch probe.  I also dropped in Tinymachines 7.4.3 for the CR10S Pro V2 which uses the Z+ endstop instead of a jumper and the Z- endstop when going from the old V1 I have to what is essentially now a V2 with the touch style probe. 

I also designed a quick adjustable probe mount since I did not feel like messing around with figuring out the specs for a fixed probe, though I did end up modeling that anyway.  I plan to finish up testing and then will update the Hydra Remix.  Although I'm happy that the Hydra Remix will soon be checked off the list and finalized, what a mess, and all from a stupid extruder arm I could have just replaced and kept on rocking.

I'm not gonna do a writeup of how to install the probe since it is really well covered by Tinymachines here, and there is another great resource page here.  I will just add this image below since I used the OctoPrint firmware updater tool to do the upgrade.  It required installing AVRDude according to these instructions, and then I just set the following in the plugin options:

After install, I just ran M502 (factory reset) and then M500 (save), then added these for the probe offset and the BMG e-steps:

M851 X0.00 Y-46.00 Z0.00
M92 E415.00

I ran a PID tune from the menus and set the probe z-offset using the menus as well. 

I removed all the contact forms on this site (that I could find) today, due to the increasing spam that is being sent though them.

It's been over a year since I designed (but never tested) a remix of the Hydra Fan System, which was modified for my CR10S Pro with a MicroSwiss hot end.  I never felt the need to change since the original extruder was doing an OK job, but that changed this week when I found it was pretty much destroying itself.  So I had some parts already printed, and a BMG clone so I decided to try it out and do the upgrade, now I'm just waiting on a cable to extend the stock cable.  Everything fits though and I have a good feeling that this could be a beneficial upgrade.  If it doesn't, it will be easy to fit a different extruder since the system is very modular.