Last modified on February 22, 2021
- 1 features
- 2 Print
- 3 Print file
- 4 Connections
- 5 ESPEasy configuration
- 6 Step-by-step video tutorial
- 7 Front cover
- 8 Upcoming improvements
- 9 User boxes
There have been many blog readers who have asked for a 3d printed box for him CO2 meter.
Voucher, challenge accepted!
I have designed a custom box for 3D printing, simple and easy to print, no need for supports or bridges.
The main of features and benefits from the box, are as follows:
- Easy to print (no supports or bridges).
- Design with thermal dynamics to conduct heat away from the CO2 sensor
- System of NodeMCU installation without welding (optional)
- Ready to install a 0.96 ″ OLED display
- Prepared for the installation of LEDS for color warnings
- Ready for buzzer installation
- Design of custom vinyl front cover
The box is very easy to print, although, as it has a certain surface, it can cause warping problems (lifting of the corners) depending on the printer and its settings when printing with ABS.
Me I have printed the prototype with PETG, even though could be made perfectly with PLA.
In a way the PLA would be better because it is more stable and the measurements are more accurate. This is especially important for the pins on the NodeMCU (I had to go over the holes with a small drill bit).
Box does not withstand any stress and is structurally robust, so we can print it with an infill of the 10% without any problem or risk of being too flimsy.
The printing time, in my case, has been about two hours. Depending on the printer, speed and quality desired, the printing time can vary quite a bit.
I have left the STL file for printing on Thingiverse. You can access it here.
The back cover is missing, which, at the moment, I have not designed. This is a first version and I will probably make another version with some improvements that I want to introduce, so I will take the opportunity to design the back cover for the new version.
If I didn't get to make the new version, I would design the back cover for this one.
The video covers the basic details required for connecting the OLED display. For more information, I recommend viewing the article Connect an SSD1306 OLED screen to ESPEasy.
Diagram with the connections of the NodeMCU to the SSD1306 screen.
Diagram with the connections of the NodeMCU to the WS2812 LEDs (Neopixel)
For more information, I recommend viewing the article Connect and control WS2812B LEDs to ESP8266 with ESPEasy.
Diagram with the NodeMCU connections to the MH-Z19 or Senseair S8 module
Both modules, MH-Z19 or Senseair S8, are compatible in terms of connections, so the connection will be identical.
Once we have made the connections, we have to configure ESPEasy so that it recognizes the devices and include some simple rules so they behave the way we want.
Basically, we will have to do the following:
- Add the MH-Z19B sensor to ESPEasy
- Add the SSD1316 display to ESPEasy
- Add WS2812 LEDs to ESPEasy
- Activate the ESPEasy rules engine
- Add a rule so that when it turns on it does so with the LEDs off
- Add a ruler to change the color of the LEDs depending on the CO2 level
Add the MH-Z19B sensor to ESPEasy
This article, which you are reading, is about the 3D printed box. It is assumed that you already have a working homemade CO2 Meter. If not, I recommend you see the article home CO2 meter and your video. In it you will find all the necessary details and a lot of useful information.
Add the SSD1316 display to ESPEasy
The connection of this screen is very simple and is explained in detail in the video.
I am not going to repeat its configuration here, since in the article Connect an SSD1306 OLED screen to ESPEasy You have very detailed instructions on how to connect the display and how to set it up with a very detailed video.
Add WS2812 LEDs to ESPEasy
Connecting WS2812B LEDs to our board and using them with ESP Easy is child's play. Only three connections are necessary.
Its connection and use are explained in detail in the video that you will see below, so you should not run into any problem.
I recommend you see the article Connect and control WS2812B LEDs to ESP8266 with ESPEasy where you can find all the connection details, the rules you have to create, etc.
Do you want to add a buzzer?
The box is prepared for the installation of a buzzer, In the article Using a buzzer with ESPEasy you have everything you need for connection and use.
Step-by-step video tutorial
Although the assembly is very simple, and is largely covered in the video of the assembly of the Homemade CO2 Meter, I have created a video with all the details of the boxed meter mounting, with specific instructions for connection and configuration of the OLED screen and LEDs.
In it you can find explanations, details and advice of all kinds.
Along with the STL file of the box, in Thingiverse, I also leave you the front cover in SVG vector format.
Me I have cut the front in adhesive vinyl with a cutting plotter, but you can print it with a normal printer, cut it by hand and paste it or do it with laser in another type of material.
I also leave you the front cover the format of Silhouette Studio, which is the cutting plotter that I use.
In the next version of the box, which I intend to do, I plan to introduce the following improvements:
- Expand the gap of the LEDs to 10mm to be able to install led strips standard flat shape.
- Provision of holes for the installation of 5mm round LEDs for those who prefer it (for example, to put normal RGB LEDs).
- Change the position of the buzzer to leave the front clean and allow the installation of the buzzer modules most common.
If you want to suggest any additional improvement, you can leave it in comments.
The idea It is not create several versions for different parts (for example, one for NodeMCU and another for Wemos D1 Mini, whoever wants to put a Wemos D1 Mini can leave it wired on air) but make improvements that extend functionalities or improve usability.
Some users have designed their own boxes and the truth is that some have improved my design by a lot!
If you've designed a box, don't be shy, tell me to include it.
Next, I leave you the boxes that the users have designed with the links to download them.
Danimod User Box
A box very elegant, In my opinion. In the following video you can see it in detail.
You can download it here.
The screws for the cover are M2x7.
Danimod has also designed an optional stand for your box which, to me particularly, seems to me to be phenomenal. You can download it from the same site. In addition, as you can see, it has equipped its meter with LEDs that change color with the level of CO2.
Nacho User Box
Nacho (nacho at pearquitectos.com), is expert architect in healthy and efficient houses, and has designed a box with a very interesting design, inspired by Netamo.
You can download the STL out of the box from here, so you can print it.
Contracovid User Box
User box Countercovid, based on that of Danimod (in fact, you can use the same lid), it is an adaptation to fit the Dupont connectors (so as not to have to weld) and dispensing with the OLED screen.
In the next photo you can see the internal distribution of the components.
You can download the STL from the Contracovid box from here, if you want to print it (you know, use the same cover from the Danimod box).