💪🏺Increasing the strength of your vasemode prints

Generally speaking, vasemode prints are awesome! They are fast, did not often fail and also have no stringing at all cause there is no retraction used. But there is also a downside. Vasemode prints are not that rigid as regular prints because they only use one perimeter during the whole print. So how can we increase the strength of a vasemode print? These are the 3 techniques I use to make my vasemode prints more rigid.

Vases in comparison, from no fuzziness left to full fuzziness right

Technique 1: Overextrude / upgrade to a bigger nozzle

Sounds stupid, but one simple way to add more strength to your prints is to extrude more material. This can be done by switching to a bigger nozzle like a 0.6mm one. The bigger nozzle diameter will extrude more material which makes the one perimeter stronger. But what if you don’t want to upgrade to a new nozzle cause you only print sometimes in vasemode and want to keep you standartd 0.4mm nozzle that may came with your printer?
Well than you have the possibility to overextrude material. If we advice the slicer to push more material through the hotend then regular, that will also end up in thicker and more rigid perimeter. But this comes with a downside, overextruion is limited because it will clog your nozzle if you get to greedy with the material. E.g. if you try to push material for a 4mm perimeter to a 0.4mm nozzle, which would be 10x more than regular.

In my tests I found out that you can safely extrude twice the material through a standard 0.4mm nozzle. So setting the default perimeter/wall width to 0.8mm will increase the strength of your print in a decent way.

Wall settings for over extrusion

Further, keep in mind to slow down your print speed and increase the temperature a bit while overextruding. This gives the material more time to melt in the hotend and prevents clogging.

Technique 2: Use fuzzy skin

I found this “trick” recently by accident cause I forgot to uncheck that option as I printed some decorative vases. As I saw the final print I was quite impressed how stiff the model actually became and after thinking about the “why” it also made kinda sense to me.

Here are my 5 Cents on that. On a fuzzy print the nozzle wiggles during the extrusion process. Because this wiggle is kinda random it creates tiny pits in the perimeter which, if you see it kind as a half sphere, gives the perimeter more structural integrity.

Of cause this has also a downside. If you get too fuzzy, your perimeter start to get holes and if you need a very smooth surface you can totally skip this technique. But to add some more strength to a simple vase, this is a very good opportunity.

Vases in comparison, from no fuzziness left to full fuzziness right

Technique 3: Design your model for vasemode

This technique is the holy grail of strong vasemode prints and mostly dedicated to designers. You can actually design your models in a way that they are more rigid in vasemode. This is done by a couple tricks which increase the strength of your model and keep it vasemode compatible.

Lets imagine you want to have a square tube with an insider and outside perimeter.

Step 1.

First you have to create a cut through your whole model, from bottom to top. This makes the print compatible with vasemode because the cut connects the inside and the outside perimeter. Now it comes to the trick.You make the cut so thin, that during the printing process, the two sides of the model will melt together and creating a seam.

The Seam is at the top center

Step 2.

To increase the strength you can now add ribs between the inside and outside perimeter. This is also done by cuts witch don’t go completely through the model and form a u-turn during the slicing process. The distance between the outside perimeter and the cut is two times the nozzle diameter if you are using Cura. The width of the cut was in my testing one times the nozzle diameter. Everything smaller was wiped by Cura during the slicing process🙄.

If everything works as expected you should see, that the end of the u-turn touches the outside perimeter. These ones will also melt together during printing.

Ribs are touching the outside perimeter.

After the print finishes, you can see that both perimeters are connected by the ribs which makes the vasemode print extremely strong depending on the amount of ribs you used.

Printed result

But as same as the both other techniques, this one has also his downsides. First you can’t do this with downloaded STL files cause the designer has to follow the named tricks during the design process. So it’s more dedicated to the people who creates their own models using CAD software.

Second, because this technique relies on margins and dimensions of the perimeter distances, you can’t simply scale these kind of models. E.g the model above could be scaled in Z but not in X or Y cause this would increase the distance from the ribs, seams, etc. If you have an even more complex shape you also can forget the Z scale.

Last not least, this technique is time consuming. You have to tinker a lot to find settings that work for you and you also have to keep the vasemode tricks in mind during the whole design process. But all in all this will give you the best results for strong vasemode prints.

Conclusion

As shown above there are several possibilities to the increase the strength of your vasemode prints. From super simple to more complex. You should check them out to see which one works best for you 🤓. If I had to choose one to start with. I would try the fuzzy skin technique, because its super simple to use and require not a lot of changes in the slicer.

🏡🌡️🖥️Monitor your central heating with ESPHome

Recently I found some nice Dallas temperature sensors on AliExpress. These sensors came with a metal probe enclosure and one meter wires attached to it. I ordered some without a special reason just have them around. Couple days later I watched a YouTube video from Sir GoodEnough where he added such sensors to his cottage heating system. That inspires me to add these sensors to my central heating as well 🙃.

Bench test of the sensors

The Idea

To monitor the temperature of my central heating unit I wanted to place four sensors to the system. One at the hot water tank and three to the heating system itself. All sensors must be attached outside the water system. That way the system stays untouched and I don’t have to be afraid about leaks, etc. All sensors are linked together on a perfboard which also houses a D1 Mini that runs ESPHome to get all the data into Home Assistant. This is a similar design as in my DIY Yardbell project.

Parts list

For the DIY heating monitor we will use the following components:

*Some links are affiliate links. If you use them to buy the parts for your project you will help me and my next project. These links will cause no extra fees or costs to you

All components expect the enclosure and one probe

Let’s Go!

Let’s start by placing the screw terminals onto perfboard. I chose to use red for VCC, black for GND and green for data. That way I don’t get confused during connecting the sensors to the board later on. After placing the terminals, solder them to the board. Thx to the sensors, all data ports can be soldered to one dataline (Pin) on the D1 Mini so all data terminals can be bridged.

Downside of the perfboard with the screw terminal soldered on to
Downside of the soldered perfboard

After that, figure out where the D1 Mini has to go. I placed it with the USB port up. That way the pins for VCC, GND and some data pins are facing the screw terminals. Further I soldered one male and female pin header to the board. With this setup it’s impossible to put the D1 Mini in the wrong orientation later on.

Top view of the perfboard and the D1 Mini with soldered connections.
Soldered D1 Mini pins

Choose a pin

Because all sensors will use the same data pin, connecting the sensors to the D1 Mini is quite easy. In my case I selected pin D2 (GPIO4) as the data pin. To prevent the pin from floating, its recommended to use a pull up resistor between data and VCC. ESPHome recommends a 4.7kΩ resistor but the board will use 4 sensors in parallel, so I decided to go with a 1KΩ resistor to create a strong pull up. Choose the value that fits for your setup.

Top view of the board with the soldered data pin connected and the pull up resistor in place
Data line and pull up resistor connected soldered from the backside

Finalizing the board

To provide the sensors with power, they must be connected to the D1 Mini. This is done as same as the data line, from the backside of the board. Its possible to simply bridge the pads or if you have a small spare wire, like me, just use that to connect the screw terminals. I used both methods to connect the GND and VCC terminals to the D1 Mini. The D1 Mini it self uses the power from the micro USB port.

Top view of the backside of the board
Backside with connected VCC and GND

Into ESPHome

After all the soldering, its time to connect the D1 Mini and write / flash the ESPHome sketch. You can do that using the ESPHome web flasher. The easiest way to configure the sensors is to follow the recommendation in the ESPHome documentation. First prepare the basic sketch and connect one sensor. Then check the logs for the sensor address to specify it in the sketch and reflash the sketch after configuring the sensor. Repeat this process with all sensors.

Basic ESPHome sketch

esphome:
  name: heaterroom-thermostat

esp8266:
  board: d1_mini

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "auto-generated-key"

ota:
  password: "auto-generated-password"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Heaterroom-Thermostat"
    password: "$up3rP4sSw0rd"

captive_portal:

#temperature sensors
dallas:
  - pin: D2
Screenshot of logs after connection the 3 sensor
Logs after connection the 3 sensor

The final sketch should look similar to this one.

Final ESPHome sketch

esphome:
  name: heaterroom-thermostat

esp8266:
  board: d1_mini

# Enable logging
logger:

# Enable Home Assistant API
api:
  encryption:
    key: "auto-generated-key"

ota:
  password: "auto-generated-password"

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Heaterroom-Thermostat"
    password: "$up3rP4sSw0rd"

captive_portal:

#temperature sensors
dallas:
  - pin: D2

# Individual sensors
sensor:
  - platform: dallas
    address: 0x61b0d35b1f64ff28
    name: "Probe 1"
  - platform: dallas
    address: 0x753d852d1864ff28
    name: "Probe 2"
  - platform: dallas
    address: 0x0f9e4b221864ff28
    name: "Probe 3"
  - platform: dallas
    address: 0x6623872d1864ff28
    name: "Probe 4"

If all sensors are configured properly the ESPHome device can be added to Home Assistant. It shows up as a regular device and promotes all the configured sensors which then can be renamed and added to a Home Assistant dashboard.

Screenshot of the home assistant entity view
Device shown in Home Assistant

Mount all the things

With all the configuration done, its time to mount the sensors to the heating system. I mounted the sensors at 4 points. The first one is the hot water tank. The sensor connects to the exposed metal on the top of the tank which is covered by isolation material.

View of the hot water tank with the sensor connected
Tank sensor

The second and third sensor connect to the fore-run of the heating system. One before and one after the pump. That way I can see if something is wrong with the pump, if these temperatures differ much.

Side view of sensor connected to the fore-run
Sensor connected to the fore-run

The last sensor connects to the return-run of the heating system. That measurement must always be lower than the fore-run, otherwise something is badly wrong 😂. All sensors are fixed with zip tiles and covered by some isolation material to get the most accurate readings.


Last not least, I placed the board into a electrical junction box to protect it from dust and powered it with a phone charger. Pick an enclosure that fits for nearly every enclosure should work.

Top vie of the open junction box
Board in junction box

Sum Up

And that’s it! Your central heating system can now be observed in Home Assistant. The readings might differ a 0.5 – 1.0 degree from the in-pipe-thermostats, but this should not be a big deal if you’re monitoring such an old system😉.

If you like this project feel free to share it and if you have further questions, hit me up on twitter or in the comments below😎.

⚙️🎃💡Automatic Halloween pumpkin light

Recently we went out to carve some pumpkins for Halloween. After we finished our beautiful work my son asked me: “Dad, will they glow in the dark like my marmalade Lamp?”. My first answer was “no”, but then I thought, “Hey, why not 😄?” and on the same day I went to tinkercad to design a circuit.

The automatic Halloween pumpkin light in action

The Idea

I wanted to have a light which turns on automatically when it dark outside. This light must be kinda watertight because it will be used outdoor inside a pumpkin and the circuit should be easy to build. I ended up with this circuit designed in tinkercad.

Image of the circuit from tinkercad
Basic circuit (image from tinkercad)

The circuit works as follows. The N-Channel MOSFET works as a switch. If the voltage on the gate (left pin) is higher than 2V, current can flow from the drain (center pin) to source (right pin). This turns on the LED. The gate is controlled by two resistors. One fixed value and one LDR which has a high resistance in the dark and a low resistance when its exposed to light. These two resistors form a voltage divider and control the voltage at the gate.

So during the day the resistance of the LDR is low which decrease the voltage at the gate and turns the MOSFET including the LED off. From dawn on the resistance of the LDR is getting higher which increases slowly the voltage at the gate. This also slowly turns on the MOSFET and the LED, perfect 😁.

In the real circuit I changed some parts because they weren’t available in tinkercad. The red LED incl. the dropping resistor will be replaced with an cheap white LED strip. The batteries will be replaced by an Li-ion battery incl. changing controller. Last not least I added a switch to the battery to turn everything off if its not in use for a longer time.

Parts list

For the automatic Halloween pumpkin light we will use the following components:

*Some links are affiliate links. If you use them to buy the parts for your project you will help me and my next project. These links will cause no extra fees or costs to you

All components needed for the project
All components

Breadboard time

Before I fired up my soldering iron I hooked put together on a breadboard, because I wanted to know which resistor value works best for my LED strip and MOSFET. First I started with a 100K resistor but using that value the gate voltage was only 2.2 volts, if there was no light on the LDR. Because I wanted to have a higher voltage at the gate, to turn the MOSFET completely on, I went with an 86K resistor. That increases the voltage at the gate to about 2.9 volts which turns the MOSFET nearly complete on.

Besides of finding the right resistor value I was also able to measure the current used by the whole circuit. ~130 mA incl. the 20 LED’s, not bad🤓.

Circuit from tinkercad on a breadboard
Circuit on a breadboard

Start soldering the power unit for the Halloween pumpkin light

I started with the battery and soldered the wires to it. If you’re like me, add some electrical tape for extra safety.

Top view, battery with wires
Battery with wires

After that, I cut the positive wire in half, added heatshrinks and soldered the switch to the wire.

Front view of the soldered switch to the battery
Soldered switch

To complete the “power unit” I added the USB-C charging unit to the battery by soldering the wires to the battery pads on the circuit board.

The charging unit wired to battery
Wired charging unit for the Halloween pumpkin light

Move on to the transistor circuit

Then I moved to the tricky part. Even if the circuit looks simple it kinda confused me during soldering, so I had my tinkercad circuit next to me and double checked every wire if I had to add a hearshrink or not.

With that preparation I continued soldering wires to the LDR. Because it will be exposed to the weather, I added some transparent heatshrink to protect the LDR from the rain.

top view of LDR with wires and heatshrink
LDR with wires and heatshrink

After that step I soldered some wires to the LED strip and drilled two holes in my enclosure to put the wires from the strip and LDR trough it. It’s important to do that before soldering the other components to the wires! Trust me, I did that mistake about 100 times 😄.

Top view of LED strip and LDR wires inside the enclosure.
LED strip and LDR wires inside the enclosure

With my tinkercad drawing next to me I added heatshrinks to the LDR wires and soldered them to the gate (left pin) and the source (right pin) of the MOSFET.

LDR wires soldered to the gate and source of the MOSFET
LDR soldered to the MOSFET

To create the voltage divider I added the 86K resistor to the gate (left pin) of the MOSFET.

86K resistor soldered to the gate of the MOSFET
86K resistor added to the gate

Then I soldered the negative LED strip wire to drain (center pin) of the MOSFET. Same as before, don’t forget the heatshrink 😉.

Topview of the negative wire soldered to the drain of the MOSFET
Negative wire soldered to the drain of the MOSFET

To create a connection for the “power unit” I cut off a piece of wire and soldered it to the positive wire of the LED strip. Then I slid a heatshrink over the two wires and moved the heatshrink from the LDR up to the MOSFET before I soldered the two wires to the resistor.

Deatil view of the positive wires connected to the resistor
Positive LED strip wire and spare wire connected to the resistor

Almost done

After finishing the voltage divider I slid up the heatshrink from the drain of the MOSFET and soldered a negative spare wire to the source of the MOSFET. This wire will be also connected to the “power unit”.

Image of the complete soldered MOSFET
The finished MOSFET

In the last step I secured all connections, heated up all heatshrinks and added a big one which fit over the MOSFET. So I ended up with a nice little package.

Front view of the MOSFET with all heatshrinks shrinked
MOSFET with all single heatshrinks
MOSFET with large heatshrink
MOSFET with large heatshrink

The final steps

To complete the wiring I soldered the two spare wires from the MOSFET to the “power unit”.

Image of the final soldering
MOSFET soldered to the “power unit”

Now it was time to put everything into the enclosure and wrap the LED strip into the transparent heat shrink. Last not least I added some hot glue to the holes of the enclosure to prevent moisture inside the pumpkin 🎃.

Image of the finihed project while its charging
The finished automatic light during charging

Sum up

And that’s it, the automatic Halloween pumpkin light is done🎉. If you turn on the switch and cover the LDR with your hand, the LED strip starts to light up.

This was a really fun project; from the idea to tinkercad over to the breadboard till the final soldered result.

As always, if you like this project feel free to share it. If you have any questions, just write a comment or ping me on twitter 🐦.