DIY printhead

Hi,

First of all, excellent thread! Thank you for all who have invested great deal of work into the research.

I will need the ability to eject tiny amounts of liquid in my next project, in my case what would really count is how much liquid will be ejected within given time (Let's say a second). I need to be able to control this down to at least 1/100. The exact thickness and uniformity of spray does not matter much as long as it stays under 1mm.

What really bothers me though is: I want to make a product / kit out of this (Open Sourced). But I suspect that this work would violate about gazzilion patents and I might end up sued all over.

Any opinions on this?

Cheers

look at this : [www.nanopaint-tech.com] is possible to built actuators ?

Quote
don.key
Hi,

First of all, excellent thread! Thank you for all who have invested great deal of work into the research.

I will need the ability to eject tiny amounts of liquid in my next project, in my case what would really count is how much liquid will be ejected within given time (Let's say a second). I need to be able to control this down to at least 1/100. The exact thickness and uniformity of spray does not matter much as long as it stays under 1mm.

What really bothers me though is: I want to make a product / kit out of this (Open Sourced). But I suspect that this work would violate about gazzilion patents and I might end up sued all over.

Any opinions on this?

Cheers

Inkjet technology has been around for quite many years. The early patents have been expired. If you build your ideas on these patents, it should be pretty safe. Also, most relative patents these days are about the high density multiple or even matrix of nozzles. What kind of company would still put serious money into a single nozzel print head? (just my thoughts, haven't done the patent search)

This is a rather interesting and informative thread. I feel the piezo actuator is a weak part, which was initially designed for making noise. The energy it can generate appears limited although successful test has been done to show it's kind of working. I'm thinking to use the ultrasonic vaporizer piezo disc. It comes in 16mm and 20mm diameter, e.g. [item.taobao.com]

Yadavid,

I looked in to this for some time now. In particular the ultrasonic vaporizer piezos. I kind of abandoned it because piezos are a pain in the... Particularly if you don't have a fancy machine shop to make the nozzel.

The atomizers are interesting, and fun to play with but they are pretty different from the bimorphs. I started by building an atomizer with a simple (terrible) circuit. It worked. That much was fun. I could create gysers of water with them. With a little work, I was able to eject droplets from a nozzel. Then I hit a wall. It was too difficult to control, too slow, too unpredictable, too inefficient, ... I saw potential, but the physics is way over my head.

BTW, I recommend a book "piezoelectric ceramics: principles and applications" by APC. It's a quick read, and gets to the point.

I moved on to syringe pumps and had better luck. Better, of course, being a relative word. It still interests me, however.

Hi all,

I just wanted to post that I gave it another shot. Keep in mind, I did not read all the posts so if somebody already tried this, forgive me. One of the biggest annoyances for the the designs I saw on the wiki was the complexity/assembly. I have endlessly toyed with other complicated assemblies and designs... Maybe these can be designed to be much simpler. It took me 15 minutes or less to build a working device.

Basically: A small piece of 1/4in acrylic. A few holes drilled to provide an inlet and an outlet flush with the surface of the acrylic. (I used small PCB drill bits to make small holes.) I used a small buzzer (1/2 inch-ish) acrylic and mounted it using 8mil x 1/2in double sided tape. I cut a small circle in the tape to leave the center of the buzzer unobstructed. I only used a dremmel and eyeballed the whole thing. I was a bit surprised when it worked.

On its own, however, I haven't overcome any of the 100 other annoying problems with this kind of system.

Video showing the device in action:
[www.youtube.com] (my first attempt at filming was quite disappointing... I didn't have time to make a better video.)
[www.youtube.com] (this is an improved view)

On a related note, this video shows the work I did with atomizer piezos (in this case it was running at 2.8MHz). It was... a bit too powerful. The plastic tip melted after a few seconds of operation.
[www.youtube.com]

Edited 1 time(s). Last edit at 09/29/2015 12:24AM by fosterb.

Both of your projects are excellent JohnRPM.
Could you contact me at bbryanmd@aol.com?
Thanks for this info!

Good thread and good things you do here! Just continue doing! We`re all waiting for the results!

Great job! Like Peter, I'm keen on more details you're willing to share. Your insights are valuable, and expanding on specific aspects, challenges, or key learnings could provide even more depth to the community. Looking forward to any additional information you might share. Keep up the excellent work!

... check the date of the last post ... seems quite old, so maybe no reaction to await

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]