Here's another thought:
Mean Well 5VDC 5A Power Supply
This provides 5VDC 5A, from an AC input. Connect it directly to the main supply and you'll have enough for your Pi 3B+, camera, etc. If you put it before the switch, the Pi is independent. Put it after, it goes on and off with the printer, although you have to be careful about issuing the shutdown command to the Pi, first.
I got thru my install and it seems to be working great!
I used a 40mm 5v Noctua fan, wired to the 5v output of the lm2596 step down voltage regulator.
the case took about 12-16 hours to draft :-/ and its still not perfect.
When i find myself with too much time, i will probably make a few tweaks to my case (i drilled some holes i didn't need) as well as the factory mobo case to my mk3s to get everything perfect. I also want the fan to turn on when the CPU reaches a certain temp but that's another phase of the project...
Nice. I recently modified my pi case to incorporate a noctua 5v fan that i connected directly to the pi's 5v and ground pins. Figured always on is good for my situation since those fans are so quiet. @tedder42's octopi support plugin kept warning of CPU capping due to overheating, and I figured I might as well fix it...my case was completely closed without any vents prior.
Did you drill the screw holes or model them? I've got a clever technique of modeling the bolt holes in Fusion 360 if you're interested.
I just used the a hole tool... nothing crazy. There are a lot of sloppy features in my model. i don't plan to sell it and no one will know unless i tell them so i will probably not correct them.
I ended up just deleting the separating parts of the USB/Ethernet jacks in my case and left everything else solid. Seems to draw the air nicely across the board. If I remember correctly, temps were showing ~39C after putting it all back together.
You saw my snazzy cover? I put holes and slots in the ‘scad.
@Roger_S That is a snazzy idea. would you share your case model and an outline of your trails? I'm running a Pi 2b on my Mono Mini, going to a multi-port USB PS. I have the voltage monitor plug-in installed & have never seen a flag. My CPU ala 'top" during a print job runs 15-40%. A little memory and no swap. My 2B is not taxed. I am using eth0 not using wlan0. I have 3 primary workstations I connect with to submit jobs. A HP mini110 - ATOM i686 w/ Lubuntu, an Original Samsung Chromebook, and my Pi3b+ that I use as a workstation. I'm essentially in a low power CPU usage environment. I watch power monitoring. I'm running enough Pi's now that I'm pondering putting NAGIOS on a PiZW, just to watch my devices ala SNMP. Those are my findings, thoughts, ideas. IMHO
JLH
