Tech

3d food printer

New 3d food printer, first steps

Dev, Tech, Uncategorized

My 2019 3d food printing resolutions included, not only, a new 3d food printer. Pinya4 is a new iteration on the saga. The fourth one.

As mentioned in this previous post the main goals for my new 3d food printer Pinya 4 are:

  • Easy to use
  • Automatic multitool
  • Clean access to printing area
  • Easy to clean

My first iteration, does not tackle all these features. In fact it mostly focuses in a single one. Clean access to printing area.

The reason for this is to actually learn (start to) a bunch of new making skills:

Welding

From day one I wanted to use stainless steel for my printer. It is the “pro” cooking appliance material. Welding the body felt like the right way to get a sturdy frame. Also I got excuse to my first steps into TIG welding.

Following pictures show the evolution for the new food printer first frame.

Of course this took way longer than expected, but through a some trial and error I got the frame done. Stainless steel is a harder material to cut, compare to aluminum, so that was intense. I was happy with the results and I even ended up welding the bolt joins!

CNC

This was a fun one, I wanted the new food printer to have as much as metal parts as possible. I quickly gave up on stainless part for my learning process with CNC. Thanks to the support from Hannah and Boris from New Lab I was able to jump on the Haas and machine the main plate and biceps for the printer.

The following parts are the printer biceps:

SLS PARTS

Having quick access to New Lab printing service, it was a no brainer to take advantage of it. I printed the end effector, the ball joint cup and bicep to shaft thingy.

I used abuse FDM, but for more complex and tiny parts like the ball joint cup it makes a HUGE difference, thanks Alex!

Endeffector picture:

Following picture is the second iteration of the ball joint cup:

CONTROL

My last 3d food printer was using a Smoothieboard. Instead the new 3d food printer uses a Duet3D.

Not a lot of reason was put into this change. Basically I wanted the firmware to have rotary delta kinematics, I was curious about the wifi integration, and wanted to try the RepRapFirmware.

Lessons learned

NO CAD???

I knew that not designing the whole printer in CAD, I use mostly fusion360, was a mistake. But at the same time I knew that If I had to put the hours to make a beautiful and full featured CAD I would had never started the printer.
Due to the lag of a proper full design, I did the following mistakes:

  • The printer is shorter in height. By almost 90mm!!!
  • The tension mechanism of the motor belts is BAD
  • The endstops set up is not friendly
  • the ball joints are a never ending mess
  • …

Although beyond this issues, I am really happy on how the printer looks and feels specially thanks to welding and cnc wise.

Stainless steel is bouncy

Being this my first (and so far) only stainless steel welding project I had zero idea about how to size the body. I used 1/2 in flat bar, that turn out to make the body quite springy.

Next iteration will have a stronger design, or so I hope!

Gravity (weight distribution)

Never thought about this until I had the first parts on my hand. The hanging head of the printer (includes motors and arms) is pretty heavy! So the tower needed to be at least twice as heavy. Right now it is not and I need to balance the printer with a pot full of coins.

Ball joints

Without thinking much I moved from magnet hold to spring loaded ball joints. I am already into my 3rd design iteration, and for some reason I feel they wont be the last one.

First iteration used only one spring, what made all the joints S-N-A-P

Second iteration used two springs, and a bigger “cup” to slide around the ball. I felt the surface in contact between socket and ball was too big and decided to do a third iteration. Probably this wasnt needed. Although I feel, deep down inside of me I was hoping to solve in hardware calibration issues in the printer.

Rotary delta?!?!

Where to start here. This is my first rotary delta. In fact, I build the hardware before I even had a slightly idea of how to make it work. Obviously I still dont. I have managed to do some quick print, to clearly realize the need for a proper calibration day.

Printing food I have never worried too much about calibration, I dont think 1mm up or down matters much, but at least having a flat layer is a must… so it is clear that that is my next step!

Conclusions

There is still a long road ahead to get Pinya4 up and running, hopefully sooner than later we will get there. Once we have a solid foundation is when things are going to start getting fun, trying to solve some of our early design goals! multitool anyone???

Thanks a lot! Cudos to you if you made it all the way down here.

BTW, if you like what you read here, consider supporting us on Patreon that makes a world of a difference and help us to make more awesome things!

Coaxial nozzle

Printing food with a coaxial nozzle

Dev, Tech
Coaxial nozzle

I like making things. Sometimes too much. I made my first coaxial nozzle 4 years ago and until this year I did not give it a decent shot. Wanna learn more about my first experiments with it? Lets do it!

First lets explain properly what is a coaxial nozzle. It is as simple as a nozzle inside of another nozzle. This allows to “wrap” a material with another. This would make sense for example to have a soft material inside and a “harder” one outside that acts as a wall.

BTW the idea of using a coaxial nozzle was suggested by Will during my time at Pier9.

Making

The coaxial nozzle is made out of 2 parts. Inner and outer nozzles. It is easy to assemble the inner nozzle screws into the outer one. Both nozzle sections have inlets for each material. I use small luer-lock connectors.

Both parts were made using a lathe and a mill. Probably the hardest part to make the nozzles is the thread that mates both blocks. This is important because is what ensures that once the two parts are locked, both ends of the nozzles are flush. But overall as long as the nozzle diameter are not too small, I feel is fun project to make.

Testing

Once I had the nozzle made was time to play with it. I first started with manual tests, to later move on to printer test.

The first manual tests showed that the “bowden” like extruder required a loooooooot of force to push food through the small tube. By bowden I mean that the food travels through a tube between a reservoir/syringe/cartridge to the nozzle.

Extruders attached to coaxial nozzle

Initially I tested motorized extruders like this one:

Lead screw extruder

This showed not to have enough force to push most of material so I had to design a stronger extruder.

Bigger linear motor extruder

The truth is, that after the first results, I was a bit disappointed. I used mashed potatoes and did not like the results at all. Specially printing anything with coaxial nozzle requires an extra layer of complexity not just to run the hardware but to come up with the right sofware to build the GCode. Honestely I was disappointed, and stopped working on the nozzle for a while.

Coaxial nozzle test

Fast forwarding into the future (current present – a few months ago) I decided to give it a go. With a two differences; new extruder that simplifies gcode/toolpath generation and different test materials.

I moved from motorized extruders two pressure based. Because they are easier to control, using a solenoid that goes on or off to print. The obvious trade off here is precision but that should not be a problem when learning to use something new.

It was also exciting, for me, to try to design and print a cartridge holder with a seal that could be used as an air compressed extruder.

Cartridge air pressure holder

If you are reading this, and you want to get one. Send me a DM on Instagram, I might have something to offer 😉

For the new set of tests, I switched “material” to Greek yogurt and food colorant. Also each test required a custom build tool to generate the toolpath that control each coaxial nozzle outlet.

1ST TEST

The 1st pattern was based on alternated dots with different color. This was to test the precision of the new air pressed extruder using this nozzle. Pressure used was 2-3 bars.

A really interesting artifact happened when trapped air bubbles, burst at the end of a dot, creating a ring effect when the outer coaxial nozzle was used, check previous picture.

2ND TEST

Second pattern was a snake shape. This time both exits were printing at the same time. It was really interesting to see how we could encapsulate a material inside another. It was hard to have a good consistency but not impossible. My favorite effect was cutting with a knife the lines after printing them.

3RD TEST

The third test was first attempt to add a third dimension, or layering. It was fun to try, but greek yogurt by itself doesnt have a lot of consistency to hold its shape.

The following video shows the design app:

And here you can see a print test:

CONCLUSIONS

During the test I felt a bit hopeless of this technique, but now as I review the results I see, with a bit more of perspective, what coaxial nozzle could do.

Ideally I would like to improve, the shape of the nozzle (current one being to large), test more materials, and figure out a way to have more height on the prints.

Setting up our 3d food printing workshop

Tech

In this week’s video we present the second part of our awesome memories, from the 3d food printing workshop at Fabcon 3D.

We just arrived to Messe Erfurt. First we discovered that the kitchen was empty and they had yet to build the sink and bring in all the equipment. But we also discovered that the organizers work fast! While we wait for things to come together, we went to do some shopping and get something to eat.

After that we set up the whole kitchen with a central table for up to 10 students. After that we dedicated the rest of the day to rehearse the workshop and too test the recipes and play with lots and lots of dry ice!

Of course we also had our epic high five moment with 3 hands!!

Aram and Jason you rock!!!

By the way if you have not seen the previous video you can watch it here.

Let us know if you wanna have fun too in one of workshops. Thank you

 

4 inlet multi nozzle test

Tech, ,

It has taken way more time than expected, but finally during our workshop in Germany. We managed to put together a demos for out 4 inled (4F) multi nozzle test.

The idea for this nozzle was simple control flavor profiles within the same dish. Kind of this Heston’s Blumenthal recipe. Still far away from this goal, but starting step by step.

Why color instead of flavor? the answer is because using color problems are easier to spot (then solve).

You can read more about it in the instructable.

Hopefully more adventures with it soon 🙂 Stay tune.

This nozzle was one of the many “ongoing” projects after my time at Pier 9!

3D Food for Special dates App by David Vilella

Dev, Tech, ,

david 2

During the last 6 months we have been lucky enough to count on David Vilella Riera to explore and push forward our vision for 3DFP design apps.

With his contribution we have started walking through the generative design path for 3DFP. His work was focused on designing an interface that was intuitive and easy to use. Moreover capable of creating customized designs based on a simple date. All it takes to use it is to have a special date in mind, it then immediately creates a unique design for your special date. The design is unique for the date, this creates a intimate link between the designer (commensal) and the dish. A completely new personal dialogue with the dish we are about to eat.

From David Vilella about 3D Food for Special Dates:

My Experience in 3digitalcooks

Firstly i want to express my gratitude to Luis Rodríguez Alcalde and Jason Mosbrucker for introduce me the 3D food printing and to teach me the basic concepts in order to reach on my second App called “3D FOOD for special dates”. Also i want to remark how they had managed my learning process with very clear and simple examples. Moreover they left me the liberty to contribute with my own ideas to design  and to build this App.

Since this, let me introduce the main reason for 3DFOODforspecialdates:  Everyone remembers the date of something special: birthday, anniversary, the day you met that someone special, the first kiss… people want to celebrate them with special details.

Finally i want to say that i admire their enterprising initiative, and i wish them good luck on their lots of projects. All my work and learning process in 3digitalcooks is shared in my github repository  and in a google drive file.

Thanks a lot.

David Vilella

Feel free to explore and experiment with the app here: 3D Food for Special dated App. You can see Pinya 3 in action printing one of his generative designs!

David thank you very very much for all the effort and endless nights working with us. Getting to understand the amazing world of 3DFP! 3DC will be always your home we wish you the greatest best with your new adventures!!!

3d food printing design tool: Yogurt Up

Yogurt Up – design tool

Dev, Tech, , , ,

Most 3d printers use the same approach to print food, building layer after layer. Does that make sense? Probably most of the time, but definitely is not the only approach.

An this is how Yogurt Up was born. Actually not. Yogurt up was born by looking at a food without caring about how to 3d print it. Everything started during my last visit to Korea, I was having dinner and my mother in law hand me a greek yogurt. Is funny how things that are so obvious some times are overlooked. After the first two spoons I realized that the texture of it was good to 3d print. And start playing with it. A week later when I was back to San Francisco and I bought 5 different types of yogurt and start experimenting with it.

Not all of them have the same consistency, obviously but I finally settle for Fage greek yogurt (we are not sponsored by them but would be cool 😉 ). The first test printing yogurt was free hand, without the printer just the extruder. That helped to try different deposition techniques. That was the instant when the non continuous dot technique started to take form.

The idea is to extrude big dots as building blocks elements.

By hand was easy to try but in order to test prints with the printer (DUH), a basic tool was mandatory to explore the parameters needed to control the technique. This was the moment the the Yogurt Up design tool was born.

IMG_7664

What is it?

This is a test design tool that created dotted pyramids. The following video is a great visual aid to understand what the app does.

How to use it?

You are going to need a 3d printer with paste extruder. I am using Pinya3.

Parameters:

General pyramid parameters:

Height where the initial layer of dots will be be printed.

The distance between the bases of the previous layer of dots and the current one.

Printer head movement feedrate without printing.

Distance to retract the printer in the Z axis between travel from dot to dot.

Initial reservoir build up pressure to start printing with a paste extruder.

Release reservoir pressure to avoid oozing material.

Dots parameters:

This is the amount of rows and columns that the base pyramid layer will have. In previous video it was 3.

Distance between the center of each adjacent dot.

Distance between the dots layer base height and the starting dot printing height.

Final dot printing height refered to the current layer of dots.

Printing dot feedrate. Affects both the extrusion and Z axis.

  • Dot extrusion [mm]

Distance to be extruded per dot.

Extruder retraction after each printed dot to avoid oozing/dripping material.

 Considerations

This is a test application, by no means I guarantee will work with your printer, therefore use it AS IS.

The output GCode start at the position x=0 and y=0.

We have tried, several different material; yogurt, chocolate mousse, hummus,… So extruding feedrate will totally depend on the material and the extruder that you are using. Actually fast prints will depend on that.

Obviously this app is open source, here is the repository just in case you want to experiment and learn from it.

3d printed yogurt