I've been testing a prototype (update) of my "Bento Box" style filter, which uses a neat ESP32 dev board that integrates a couple MOSFETs (perfect for fan control), and a nice 5v buck and 3.3v regulator.  Overall the board has been working well, but I really hated soldering the thin wires I was using to it.  I really suck at soldering, so I thought I'd try building a breakout board to slap on the dev board and make the connections somewhat simpler.  It still requires soldering, but soldering headers is much simpler than dealing with the thin wires I was using (due to an I2C hub that used JST-SH (1.0mm pitch) connectors.  Anyway, the last time I designed a PCB was when Eagle was the tool to use, and it seems that the baton has been passed to KiCad.  I'm sure Eagle was just as frustrating to get started with as KiCad has been, but if you ever use it, I have one suggestion - get the "Freerouting" plugin.  I thought it would have an autorouter integrated, so I was puzzling over where it was, until I asked AI and discovered it's a plugin.  That was an hour I won't get back, but so you won't also spend an hour messing around trying to find it, here is how to install the "Freerouting" autorouter plugin:

1. From the Main Screen for KiCAD, go to "Tools" > "Plugin and Content Manager":

2. Search for "Freerouting" and install it.  But make sure to install the Java JRE first, since I found the install hung until the JRE was installed. 

3.  To run the autorouter, it can be found under "Tools" > "External Plugins" > "Freerouting" from the PCB editor in KiCAD:

That is just the autorouter though, don't get me started on all the BS Design Rule Checker (DRC) rule violations I had to fix.  The DRC is handy and there was a similar tool in Eagle, it basically checks the PCB to make sure the manufacturer won't reject it for some design issue.  It does all the basics like checks if a pin is not connected or if some silksceen text is off by half a damn mm, but also some very esoteric (and annoying) stuff.  I spent the better part of the evening chasing down DRC errors until I finally slayed the last one.  All that said, KiCAD does work well (a bit buggy with a few things), but it is a nice package and pretty well polished.  If you want to build a PCB though, it pays to expect problems and schedule accordingly, since the learning curve is always a bit steep (and frustrating) with software like this.

But with all that wasted time, I now have a neat breakout board design that can act as an I2C hub (for three devices), breaks out all the worthy GPIO pins, has some cool LEDs (purely optional), and an optional power load switch IC, which I put on it at the suggestion of my AI buddy who said why not?  Aparently it can be handy if I2C devices lock up or get confused (they can be power reset through a GPIO from the ESP32 when it detects no data is flowing).  I tried to keep everything that was required for the basics to work as through hole components, while the optional bits are SMT (but aside from the SOT-23 package for the IC, they are all 1206 SMD parts).  KiCAD was able to export the board as a STEP so I could verify it would fit with my other models too, which was pretty cool.

I expect to have a few projects coming down the pike using this ESP32 dev board, related to 3D printer air quality monitoring, printer exhaust filtering or ducting, which will have integration with Home Assistant (for automation).

​I haven't priced out what this will cost to make, but I'm gonna give it another once over this week to make sure I didn't mess up some pinout or something stupid.  Then I'll probably order a small batch to test out.  I need to look up who the best companies are to order from.  I see a lot of ads for JLPCB and PCBWay, so I will check them first.  The breakout board will require some JST-PH connectors and some pin headers, along with a couple small though hole ceramic capacitors, which I will also need to order now that the bill of materials is set. 

All this begs the question though, why make a breakout board (which requires soldering to assemble) if you suck at soldering?  For me at least, there is a big difference between trying to solder tiny wires that really shouldn't be going into a board (aside from a prototype), and soldering pin headers which are much simpler to deal with.  Even though I suck at soldering, I can make a reasonable effort at soldering a pin header.  To help with my technique, I also decided to pick up some real flux to help me with this project, since I typically use flux core solder, and some decade old flux paste, which is not ideal.  One tool I have that absolutly rocks though is my Alientek T80P USB-C soldering iron.  It gets to 350°C in seconds.  Before I can get my bearings on what I'm soldering, it's ready to go.  It does require a beefy USB-C PD supply though (I use a 100w battery power bank since I like to work outside when possible).

Over the past couple months, I've been working with MadMopar over on MakerWorld to bring a few designs to life.  These were all his suggestions, and he did the testing, while I did the CAD design work.  It's been a great collaboration and now all the designs which we have worked on are available.

The first design, which started it all, was a P2S low profile exhaust fan.  This uses the same parts as the Bambu P2S Chamber Exhaust Kit ($20), but is lower profile, is scooted over to the left by a few mm (which resolves an issue of compatibility with some poop chute designs), and it has a magnetically attached duct design.  There is currently a tested 2" duct included with the models, and a 2.5" (untested) duct that is available separately.  This design does not allow for adding a HEPA filter though, since it's intended to be an exhaust only fan, which is lower profile for tight spaces.

You can find the P2S Low Profile Exhaust Fan over on Printables and MakerWorld:

https://makerworld.com/en/models/2970122-low-profile-p2s-chamber-exhaust-fan-kit-ver1-0#profileId-3330760

https://www.printables.com/model/1676858-low-profile-p2s-chamber-exhaust-fan-kit-ver10

The next design is a P1S exhaust adapater, which uses the same magnetically attached ducts as the P2S design above, and the Core 200S design below.  This is a very simple adapter plate and optional TPU gasket, which attaches to the back of the P1S, where the exhaust exits the printer.  

You can find the P1S 2" exhaust adapter over on Printables and MakerWorld here:

https://makerworld.com/en/models/2945719-bambu-p1s-2-magnetic-duct-adapters#profileId-3299690

 https://www.printables.com/model/1751316-bambu-p1s-2-magnetic-duct-adapters 

The third (and largest) project that we collaborated on is a Levoit Core 200S based filter adapter for 3D printers.  I posted about this project below, where there is more info on the development.  This was a design that was inspired by  the "Perfect Poor Man's Filter" by MrFunctionalPrint, but can be printed on a P1/P2/X1/X2 without splitting the model.  It requires the full build area though, so certain conditions need to be set up on the P1 and X1 in order to print the largest parts of the design.  That additional setup is only required on the X1 and P1 though, since they have the cutter exclusion area on the front left of the build plate.  This design took a lot of prototyping to get to the point where it could be released, so it's nice to see it complete.   There are a few things which are extras that have not been released yet (such as carbon filter inserts), but those can be added later.  The license allows for remixing so hopefully the community will also add some ducts or other parts to expand the system.

You can find the design at the link below:

https://makerworld.com/en/models/2920723-levoit-core-200s-3d-printer-filter-adapter#profileId-3268061


All of these designs only come with 2" ducts, since that is the size that has been tested.  However there is also a 2.5" duct which is untested (though I have tested the screw on couplers elements in my system, which is otherwise different).  The 2.5" ducts are available over on Printables, for anyone willing to give them a test (but feedback is requested).

https://www.printables.com/model/1754424-25-ducts-for-bambu-p2s-and-p1-exhaust-see-descript

I've mentioned this in previous posts, but I thought I should start a new thread, since those posts were older and not always for this same project (but related ones).  Anyway, I've been working on a V2 of my "Marvin the MircoParticle Machine (Bento) Filter V1" which is a bento box type filter that gets placed inside a 3D printer to help reduce fumes and microparticles.  I used the original V1 design for well over a year, and it worked well, but I gave it away to a relative along with one of my printers, and have been missing it.  The V2 update has been long planned, but the problem was that the 4 wire (PWM) 5020 blower fans I planned to use have become really hard to find (and expensive).  Fortunately the basic 2 wire (dumb) 5020 blower fans are still available and relatively cheap.  The reason this mattered was that I wanted to have some form of smart control over the fans and 4-wire PWM fans make that much simpler from the hardware side of things.  It's still possible to smartly control a 2-wire fan, but it requires adding some additional MOSFETs to actually control the fans (since the fans draw more current than can be switched from a microcontroller).  This is pretty standard stuff for anyone who makes stuff with micros, and I could have just bolted a mosfet board to an ESP32 and gone on my merry way.  But recently I found a ESP32-32E board which covers all the bases, except that it lacks almost any documentation lol.

This is an ESP32-32E based board, with an onboard buck controller which will take 5-60 volts input, has an onboard 3.3v linear regulator (to give all the 3.3v sensors and the ESP32 a stable voltage source), USB-C power input (5V only) which is really only useful for programming, and most importantly, two MOSFETs which are controlled by GPIO pins (via some transistors).  They also have a four MOSFET version, but two is enough for this project.

The pinouts, which I discovered based on tracing things on my board are:

CHANNEL 2 = G17
Channel 1 = G16
Status LED = G23
Switch = G0

Those pin mappings should be considered a starting point, since I don't know if all these boards are the same (they may look similar but they could be wired differently).  I took a close look at mine (and from what I can make out), it uses a NCE6020AK MOSFET (60V/20A n-channel), with a small "J3Y" transistor (40V/0.5A NPN) which drives it.  There is also a AMS117 3.3V/1A linear regulator for supplying the ESP32 and sensors.

The design goals of the project to update the filter are:

• Use cheap 2 wire 12v 5020 blower fans
• Local fan control with high, low and off speeds
• Optional automatic control of the fans using ESPHome and Home Assistant, but only when enabled
• Optional OLED display with 4 buttons to navigate and change settings
• Optional TVOC, Temperature and Humidity sensors
• Optionally the filter can be made with just 2 fans and a switch (full manual control, without any smart features)

So far all these goals have been met, or are in progress and almost completed.  The fans are working very well at a low (70%) and high (100%) speed.  I'm testing the automation using ESPHome and Home Assistant currently, and the major functions are working OK.  The sensors are working as well as can be expected.  The  ENS160+AHT21 TVOC sensor  is pretty cheap, and combines an ENS160 TVOC sensor with a AHT21 temperature and humidity sensor in one board.  The downside is that the temperature and humidity sensor (AHT21) is used to calibrate the ENS160 TVOC sensor, but the ENS160 has a small heater which it needs to work, and that can affect the temperature sensor... which is used to calibrate the ENS160.  That said I don't think it will be a big deal, since the board will be getting airflow, and really the TVOC value is just gonna be a relative thing, so the value doesn't have to be 100% accurate.  I could add a 2nd temperature sensor, but that seems like it's just more complication and expense.

The OLED screen is small at 0.96", but it is readable.  I may update the design to add the possiblity of using a larger 1.3" OLED, but those seem to be harder to find.

The switch is the one component I am a bit concerned about, since I had to order it from AliExpress.  I didn't see any momentary RGB button switches that were reasonably priced on Amazon.  However an RGB switch is not a requirement, and a non-RGB momentary (16mm) switch could be used instead.  The RBG LED will be used to indicate fan or operational states, but other than that it just looks cool.  

I still have to make some cosmetic adjustments to the UI, but all the functionality seems to be working well.  I'm waiting on a momentary button switch with an RBG LED, but once I have that, the rest should come together, since the CAD design is over 95% complete.

Ultimately, when this project is done, I will be able to use this same controller (with some software tweaks) to control the window vent fan and booster fan which have been sitting at an almost done state for quite a while.  A variation of this may even end up in the next version of the StoopidAire CR-Filter.

6/13/2026:  The ESP Home side of things seems to be working well, but I need to tweak the screens since some of the text should look better if it's centered.  I discovered that a simple thing like centering text in ESPHome can be a bit of a pain though, since every change means a re-compile, so I'm trying to find a better way to do it.  It's not a big deal though, since it's only cosmetic, though I still want it to look decent.

I've been working on the Home Assistant side today with Perplexity, and I have to say our new AI overlords are pretty good at this stuff.  They can sometimes forget where they were, but when they get their bearings they can really put some cool stuff together code-wise.  I've tested the automation of the printer filter with my X1C, found a few bugs, optimized things and then retested, and now it's finally banging on all cylinders.  The only downside is that putting the Home Assistant part together requires two "automations" and a "timer" (which is a "helper" in Home Assistant-speak).  That is something I will need to write up, since before last week, I'd never set any of that stuff up in Home Assistant.  Really though, it's not too difficult once the basics of Home Assistant are understood (or at least grasped).  I think I'm getting there thanks to this project.  

Below is a simple dashboard I set up in Home Assistant, which tracks some parameters on my X1C, and the "Printer Filter" (which is actually sitting on my desk).  The dashboard has "sections" which are filled with "cards" that show all the interesting stuff.  The cards look like they must be hard to set up, but really it's just a couple clicks and they work, since most are pre-templated and already have the parameters set up so they are ready to go.

On the left is the X1C related stuff, including a "tile" with a "Bambu Lab Print Status Card" which is something I found in the "community cards section when I went to set up the dashboard.  Below that is an "Entity Card" with three "Entities" which are just parameters which Home Assistant (via the BambuLab-HA integration) is pulling from my X1C.  These include the "Print Status" (running, failed, idle, etc), the "Aux Fan Speed" (this is the fan on the side of the printer), and "Print Error" which is just an error status (normally OK).  One thing I didn't find was anything for the AMS filament loadout, however I need to look into that a bit more.

On the right side is where the fun begins for me.  That's the section with some of the parameters that are available from the "Printer Filter" (which runs ESPHome on an ESP32-32E).  The TVOC data is pulled from the ENS160+AHT21 module attached to the ESP32-32E, and the temp and humidity data are also pulled from that same module.  All that stuff is sitting on my desk and barely held together with some jumper wires, worn out Dupont connectors and a splash of hope (and a breadboard).  The cards on top show the "Printer Filter Mode" which is "High (100%)" currently, since a print is "running".  The card next to that is "Printer Filter Auto Mode" which is "On".  The ESPHome config is set up so the filter can be in "auto" or "manual" mode, where auto mode is required for Home Assistant to control it.  The other cards are pretty self explanatory, but I thought the graphs for the Temp, Humidity and TVOC data were really cool.  They are easy to set up in the dashboard too, since it's pretty much a few clicks and bam, there they are (no special config or coding required).  Not shown (they are below where I screen grabbed the image), are cards showing the "Printer Filter IP Address", "Printer Filter SSID", "Printer Filter Uptime" and "Printer Filter RSSI" (which is measure of the WiFi signal strength).

Now that the Home Assistant and ESPHome configs are mostly done, I'm getting back to polishing up the CAD design of the V2 filter, with a few more optimizations and goodies (all internal changes, but may be appreciated during the build).  And as I mentioned earlier, I still need to tweak the screens a bit on the filter, but that will just take some time and banging away at it till it looks better.

6/28/2026:  Since the Home Assistant and ESPHome code seems to be done, aside from some possible cosmetic tweaks to the text, I've been working on a few optimizations to the CAD design.  I also added some parts to accomodate the four types of OLED display boards with buttons that I've acquired over the course of this project.  There will now be options to use a 0.96" or a 1.3" OLED display (of which there are three types).  The 0.96" OLED board seems to be very common and consistent as far as the design, but the1.3" OLED displays seem to be more difficult to source with several variants (unless of course they are bought from AliExpress, and then it's no problem to find them).  I've found that there are two sizes of the 1.3" OLEDs with the buttons to the side (which look very similar, see pics 2 and 3 below), so I designed parts for each type to avoid problems with sourcing parts.  I also made the buttons larger and better to read.

Although I expect that people would power the filter with a DC power supply, I've made a USB-C PD trigger option as a power input.  Unfortunately, 24V fans are not really supported by the common USB PD modes, so 12V fans are the only real option for using the PD trigger.  I've also been testing some 6000rpm 12V 5020 blowers, and have found they are a nice upgrade over the somewhat generic "GDSTime" 5020 fans I've been using.  Both will however work, and I think the PWM fans I was using in the V1 of this design (which I gave away so cannot check), were not high power fans either, and they worked fine.  

Since this design is meant to be flexible, one of the goals was to make it work with a number of different budgets.  The high end design could cost $40-50 for the parts (or more depending on sourcing and shipping costs), while the low end design could be built for as little as $10.  So I've also been working to make sure the simplest builds will also have some options to use different parts.  The most basic configuration would be the fans, a power switch and a DC jack.  Some WAGO blocks will simplify wiring (but are optional), and the design will accomodate 12 or 16mm switches, with or without a wiring clip.  The swicthes I'm designing around are about 3 bucks on AliExpress, though any switch that fits a 12mm or 16mm diameter panel mounting hole should work.  Those switches (which were linked) are only for the basic configuration though, since the configuration with all the Home Assistant stuff will require a lower profile 16mm momentary switch, due to the limited space inside the electronics compartment.

Right now I'm waiting on one more batch of parts from Adafruit.  They have a neat I2C hub board, which will really help to clean up the wiring on the "smart" version of this fan.  I should be getting those parts this next week, and can then do some final test builds to check everything out.

7/7/2026:  Few things ever works out as planned seems to be a rule I keep hitting in projects like this.  I thought I had the design finalized, so printed some parts only to find that there was an interference problem I had missed.  At least it wasn't an obvious problem, but it required some major reworking of some parts which will take hours more to re-print.  I have a growing collection of parts that were almost (but not quite) there, sitting around my desk.  Fortunately I have enough filament (I hope) to complete this project in the colors I would like to use for it.

Building the prototype also informed me on how much I hate soldering tiny wires to boards.  These are wires which are 28ga or smaller so they really are not meant to be soldered into through holes on boards like the dev board I'm testing, but for a prototype it's fine.  Soldering pin headers designed for through hole soldering is much easier, so I decided to see if there was room for a breakout board on top of the ESP32, and it appears there is (though it has limitations in this design).  There is no breakout board for the dev board though, so I knew it would mean trying to remember how to design one from scratch.  I've used Eagle many years ago for a few projects and though it was difficult it still worked out, so decided to go for it.  I posted a bit about the breakout board below, which took much longer than expected but I'm happy (so far) with the result.  I haven't ordered them yet, but plan to do that later this week, once I've given the board another fresh look to make sure I didn't screw something up.

The user interface is however done, or at least enough that I'm happy with it.  I made some tweaks to it to clean up the text formatting and used Figma to help with the layout of the OLED screen.  There is no tool I found that would help to design the layout, so Figma was useful to position text and other elements (MDI Icons), on a 128x64px field.  From there I was able to use the pixel positions for the elements and bring those values into the ESPHome YAML by hand.  It saved time but is not a perfect process, which took several iterations to get things just right.  The images below show some of the screens and how the final design should operate based on the program.  The electronics side in the final design will be similar, just with another option of using a breakout board to simplify the wiring.   The rats nest of wiring in the images is actually not that bad once the wire management is taken advantage of, but since the wire manager sits where the breakout will go, I will need to design another option for wire management with the breakout. 

The last image shows a 470μF electrolytic capacitor on the power input of the board, which was put there due to the board controlling fan motors (inductive loads).  I wasn't having any problems with the prototype during testing without that capacitor, but it's one of those things which is just nice to have.  I've said this before, but I'm no expert with electronics, and have not tested with my cheap scope multimeter, but usually with motors there can be an initial spike when they start up, which can cause some instability of the power flow to the more sensitive componenets like the ESP32 or the I2C sensors.  The capacitor may help clean that up a bit, which may help in the long run.  I could also put capacitors on the fans leads, but I think that may be unnecessary since they are so small and don't pull much power.  Something to note about electrolytic capacitors is that they are polarized, so they must be installed with the stripe (with a small "-" sign) on the ground side, or they can get really unhappy and pop.  My understanding is that it's also a really good idea to use a capacitor that has about twice the voltage rating of the voltage being used.  I'm running the board at 12v, so that capacitor has a 25v rating.  I think of it like a cup, if I need to fill it up with 12 oz of water, I don't want a cup that holds only 12oz of water, a 24oz cup would be much better.  The capacitor rating of 470μF was just a guess, and was chosen since I had one handy and it should be more than enough for the job.

I haven't posted this previously, but since late March I've been working on a new design based on a suggestion from a really cool guy over on MakerWorld who needed a filter for his 3D printers.  He wanted to use the "Perfect Poor Man's Printer VOC/Fume Extractor" by MrFunctionalPrint over on Makerworld, but that design would not fit on his P1 or P2 without splitting it up.  He agreed to test the design and provide feedback, since I don't own the Levoit C200 filter (which the design is based around), so I agreed to design it.  I think he burned through several rolls of material and many hours of printing to help bring the design to the point where it's ready to share.  The upside was that he got a filter that was pretty tailored to his requirements, though it was modular enough that it should be adaptable to many different configurations. 

​I think I spent well over 50 hours on the design in total, possibly more, (the devil is always in the details).  The deisgn also evolved quite a bit from the inital idea, and was expanded into a more modular configuration (which lead to designing some additional related parts).  Probably it would be easier to tweak a design if I were using a true parametric CAD program, but mine is not that.  This is my hobby though, and I enjoy designing cool stuff, especially when it's stuff that could be useful to the 3D printing community. 

Since the design is finished now, and we know it's functional, I plan to post it soon.  What we haven't done (and don't have the means to do), is to test how well it works at cleaning the air, or any long term testing of the design.  The design is pretty similar to the Perfect Poor Man's filter though, so I expect it to be similar in how it works.

I have a few more additions I'm working on for the design, including a couple aux carbon inserts.  The design will release with 2" and 2.5" hose adapters, but I pan to release some more adapters in larger hose sizes later.  I may also open the license up to remixing, once I have some of the other associated designs uploaded, and feedback on them.  Since I don't own the Levoit C200 filter, it makes it difficult to support the models, so I think a license which lets other folks remix it is the best way to go (but again, that will be opened up a bit later).

Below are some images of the design, including some of the assembly process.  It looks a bit complicated, but it only requires 16x M3x16mm FHCS and 16x M3 locknuts, along with some 5/16" weatherstripping and superglue to assemble.  There are some TPU parts, but with some compromises, it may be possible to build it without the TPU parts.

Update 6/9/2026:  I goofed up on the icons for the lid, and put them on backwards from the way they actually work.  That is now fixed and I also fixed the images for the instructions, which relate to those parts. So now I'm just polishing up the profiles to get everything ready to post (which will be this week).  

6/16/2026:  This design is now posted over on MakerWorld:

https://makerworld.com/en/models/2920723-levoit-core-200s-3d-printer-filter-adapter#profileId-3268061​

I've been working on an update to the 20 Bin Gridfinity Cases as a side project.  The primary purpose of the update is to add snap in latch parts (which removes the need for several screws on every case).  The update will be incremental to v3.2, and I will leave an option to add screws in case somebody wants them.  Though the snap in latches have been working well in my H2/P2/X2 Spares Cases, without complaints.  

I'm also planning to add a couple design options for the top and base, with one being a hexagonal pattern which I used on my Generic Printer Spares Case, and another being just a plain full field contrasting color.  Like the v3.1 cases, these will be available in 6U, 9U, 12U and 15U sizes, with or without a TPU gasket.

Putting all the options together is gonna be a lot of work though.  I tackled the hardest ones first and am printing the hex patterned case now to test it.  The final design will have three separate profiles (one for each pattern option).  That's gonna be 27 different lids and bases which I need to set up in profiles, to cover all the options.  This should be fun.

Update 6/6/2026:  The profiles are mostly done now, but they have been a real pain due to various issues and a very slow PC that bogs down hard when I work with very large profiles and models in Bambu Studio.  I have to assemble my 2nd prototype and print a TPU gasket, to validate things one last time before I feel OK to post it.  It's getting close.

Since the X2D was announced, I've been planning to get my H2 and P2S Spares Case updated to suppot it as well.  I finally had the time to test print another case, and it looks good.  I don't own the X2D, however most of it's spares, aside from the cutters, are the same as the P2S so adapting things was easy.  Aside from a label, the only change from the P2S spares case parts, was to swap the small module for the base with one that has a compartment for holding the cutters (which are unique for the X2D).  So the X2D version will not have a specific location for storing cutters, but they will fit in any of the compartments. 

I also added a couple small lidded bins with latches, which were designed to hold spare snap in hotend labels for the cases.  They could be used for other small parts as well.  

You can find the updated spares case for the H2 Series, P2S and now X2D at the link below:

https://makerworld.com/en/models/2435448-bambu-h2-series-x2d-and-p2s-accessory-case-v2-0#profileId-2671977 

This was sort'a side quest which was suggested by somebody over on Makerworld.  They had noted that it would be cool to have some dividers in the larger Gridfinity bins, and I thought it was such a cool idea, I decided to test it out. Something which I've never liked about bin dividers however, is that they tend to be loose and never really solidly held in place.  I'm hoping that the design I've come up with address that issue.  But because there are a ton of different sizes of the bins, I decided to take it slow (until I get some feedback on the design).  Right now, I plan to release a 2x2 and a 3x3 sized bins in 6U, 9U and 12U heights.  If they work well, I may add a divider option to other sizes of the bins (currently I have 1xn, 2xn, 3xn and 4xn sizes in the "standard" bins without dividers posted).  Unfortunately the existing "standard" bins will not be compatible with the divider system, since the bin bases and lids will be different.  I plan to keep the original bins up (without dividers), and make the bins with dividers a separate (but similar) project, since the dividers come with a cost.  The lids on the divider bins is several mm thicker, which will reduce the volume a bit.  I'm running a test print of the 3x3 prototype now, and then will try one of the 2x2 bins to see how it works.

I have several other large and interesting projects going as well, with three of them being tested currently by very helpful user on MakerWorld. That user suggested the ideas for a 3D printer filtering system, and has contributed time and material to help me test them.  Normally I print and test everything myself, but those projects involved printers (a P2S and P1S) and a filter which I do not own.  Those projects will not be posted until they are ready though, since the filtering system was just recently brought up, and it will take some time to get an idea how it works.  I'm also going to be restarting work on the Bento clone V2 update, now that I have found an ESP32 board which I think can handle non-pwm fans.  I'm waiting on the parts though, so hopefully there will be more on that later.

5/26/2026:  The 2x2 version of these bins with dividers has been posted to MakerWorld here:

https://makerworld.com/en/models/2839972-2x2-gridfinity-bins-with-latching-lids-dividers#profileId-3165833

I'm planning on releasing another version (which will be a 3x3) soon.  

I recently stumbled on the "SIG SAUER K320 Inspired Folding Utility Knife" by Trent Studio over on MakerWorld.  It looks like Trent Studio has a bunch of really cool box cutter designs, but this one stood out to me.  The remix by MarkAdams is also really worth checking out (it has thinner scales and a clip), but is designed for some Coast blades which are non-standard.  I didn't want to pay for the Coast blades, but really liked the thinner profile of MarkAdams's remix, so I used his remixed parts with the blade holder from the original design, and it worked well together (shown in the 2nd pic).  

I then made a few smalll mods to the original design to tighten up the action, and add some pre-load to the spring.  This makes it a bit more difficult to open, but that is my preference.  While I was at it, I copied the MarkAdams mod with thinner scales and then added a similar belt clip with the post integrated, so the clip is held in by one of the screws.  There were several other small changes, but overall I feel they add very little to a great design (and a really nice remix).  

I friend of mine just bought a P2S, and made me probably the coolest 3D printer related project that I've seen in a while.  It's the War Operations Plan Response, or WOPR for short.  Much like myself, the WOPR spends all it's time thinking about world war 3 (though for me, that's mostly been in the past few weeks).  I'm no Ferris Bueller, so to try and understand what the WOPR is telling me, I've spent the past several hours watching the WOPR's lights blink on and off.  Unfortunately I'm still no closer to knowing if it's saying that Iran is building secret military tech under an orphanage, or if it's concerned with their advanced falafle technology, or possibly both?  Regardless, I have to assume that those blinking lights indicate that it knows what it's doing, so I can only hope that our military has this WOPR technology too.

Since my WOPR arrived in a sterile condition, I decided to make a name tag for it, so I don't forget that it's doing serious work.  Accidentally unplugging the WOPR while it's running a game of tic-tac-toe could have catastrophic consequences, based on my knowledge of classic 80's film.  

If like me, you want to be prepared for the next 'uge world war, you can get your own WOPR (by 463n7) over on MakerWorld, at the link below.  Just be sure to get the MAX7219-based 8x32 LED modules that fit tightly together, since there are some that have a small gap between the modules, and those will not work properly with this design.

https://makerworld.com/en/models/1670433-rack-mounted-led-matrix-8x96-wopr-style#profileId-1768436

Although I don't know exactly what my WOPR is saying, I sense it's anger.  So I've already cleared out my local Costco of their entire stock of Kirkland Signature 2-ply toilet paper, which I assume will be our post apocalyptic currency of choice, along with bottle caps probably.  And now I'm off to start digging a bunker / bat cave under the backyard shed.  Sorry, but there will be no pictures of that project however.

About 4 years ago, I had to re-level my dad's pool filter, and fix a few couplers on it.  At the time the fix was a bit of a kludge, but it actually lasted much longer than I expected.  This season, when he went to start up the pool, the filter started spewing water, which was due to a broken lower bulkhead fitting on the filter.  And that was due to the filter shifting again, putting stress on the fitting.  So it was time to do the job again, and hopefully better this time.  The root of the problem is the slab that the filter sets on, which had cracked pretty badly, and had to be swapped out.  I could have poured a new slab, but decided to pick up a pre-fab slab instead.  I hit the new slab with a couple coats of Thompson's Water Seal spray before I started removing the old one.  The pre-fab slab was about 3" thick, vs the 2" thick slab that was in there, so I had to lower everything, which became quite the job.  Fortunately there was one brick set below the old slab, which I could use to gauge how low to set the new base (below the slab).  That required doing one half the of the base at a time though, so I could level to the old block, remove the old block and then do the side the block was on.

Since I planned to swap the sand in the filter out, I used up the old sand, with a bag and a half of quickcrete, and some fill dirt at about 60/40 dirt and sand and concrete, to create the base for the slab, along with some concrete blocks.  I set in a couple blocks at the base level, and filled and leveled around them, to form the final base for the new slab.  Since the prior slab had settled and cracked, I did not want the same thing happening with the new one (if possible).  After the compacted base fill dried, it seems quite sturdy, so I think it will last.

Unfortunately I didn't get a pic of the new slab in place, but will grab some more pics when I finish this up.  I found that after placing the filter back, that the pool pump was too high (it also sits on the same slab).  I'm not sure why that happened, but my plan is to print a new stand for the pump, which will have some adjustment if I need to fine tune the height.  My best guess is that when the manifold was replaced years ago, the slab was already off kilter, and therefore the pump too.  It's another kludgy fix, but I don't want to hack up the stand it's on, to remove enough material to fit the pump.   I think the printed stand will be a bit better than the original anyway.  I plan to use PETG, since I don't have any ABS handy.

Update 3/13/2026: Happy Friday the 13th!  Well, as expected I have some leaks to deal with, but fortunately the saddle is working OK, and the pump and filter appears to be as well.  I plan to monitor the saddle over the summer, and if it starts to sag, I will re-print it in ABS or ASA, despite the foul smells.

The leaks I have to deal with now are in the bulkhead fittings between the filter and the Hayward Vari-Flow valve.  The old o-rings in the fittings appeared stretched to the point they did not look worth re-using.  I've purchased two sets of replacement o-rings, with the 2nd being directly from my competent local pool store, but both leaked.  The Hayward part for the o-rings is SX200Z4, and what I was sold was a generic o-ring of the same size, which should be cool.  The stock o-ring dimensions are: ID 2.25", OD 2.5", CS 0.125", and they appear to fit, but as noted, still leak (with a propper coating of silicone grease).  The valve fittings appear to be seated in the bulkhead fittings, and tighten down correctly, so nothing looks to be amiss.  Being at a loss for what to do, I decided to upsize the o-ring to a AS568-331 EPDM o-ring.  The AS568-331 has the same centerline dimension as the stock size o-rings, but has a thicker cross section diameter of 0.210".  Unfortunately, these are hard to find, so I'm getting bent over for a couple o-rings (almost $20 with shipping). so hopefully it works.

Below are some pics I took when I finished up the pool pump re-install and got the filter filled back up with sand.  The new slab just fits the pump and filter (it's 2'x4'), and I'm really happy with how it turned out (which is nice and level, and at the correct height).  But what a pain lol.

Update 6/9/2026: This has been working pretty well so far, but when I went back to check the leaks that were occuring (the ones I got the oversized o-rings to address), they had mostly stopped.  I decided that I'd let a sleeping filter lie and if the leakes start up agian, I'll try the oversided o-rings.  The PETG saddle for the pump seems to be holding up as well, though being printed in black it makes it hard to really see if it could be buckling or sagging.  I need to have a closer look next time I'm out  there.

7/7/2026:  The saddle printed in PETG has been holding up prerfectly.  The pump no so much.  I found out that the saddle seems to be a unique design for different pumps based on their diameter (no standards aside from the flange it appears).  I'm printing a new saddle to fit a different pump which has a larger OD than the earlier one I made, and I'm using ASA this time (though I'm sure PETG would have been fine too).  It's probably more important to use enough infill and walls to make the part strong enough, than the choce between PETG and ASA.