Ricoh printheads

[notsure]

Now you are finding out how Xaar makes money from charging you to have a waveform placed into the heads flashrom.

The heads used for UV inks are the models with built in heaters. You can run UV inks through unheated heads like you might see with the modified Chinese Epson UV desktop printers but they will be low viscosity UV inks at room temp. What is generally done is a UV ink with a viscosity of 100-200 cPs at room temp is heated inside the heads and the viscosity drop to ~10cPs. Xaar has some newer high viscosity heads that can use even higher viscosity inks ~1,000 cPs at room temp and ~100cPs at jetting temp (50-90C)

I also have the intention of making an ink circulation system, mainly to facilitate the heating of the ink material. At present, I am developing the nozzle of Xaar1002/1003 series, and I have completed most of the hardware design work, and I am still debugging the firmware code. Unfortunately, I do not have the waveform editing tool of this type of printhead, so I can only control the nozzle pressure by voltage.
Why did you develop this circulation system?

[notsure]

You use a drop watcher to check on the drop formation while jetting, This is how you tweak the ink formulation as well as the firing waveform.

Inkjet manufacturers keep everything secret since they want complete control of the entire system from fluids to heads and software.

Approval for your ink to be listed as compatible can cost upwards of $50k. They also don't want you to buy and sell heads from 3rd parties.

You can buy Chinese versions of many UV inks on Alibaba and similar, same for the printheads, you just won't get specs that way.

UV inks are formulations of monomers and oligomers. The monomers are lower viscosity with qualities of being an active solvent, viscosity reducer, adhesion promoter, etc. Oligomers are higher viscosity components that give the ink its strength and flexibility. Photoinitiators are with light what triggers the change from mono- and oligo- to poly-mers. Other components are things like pigments or dyes for color, controls for surface tension, matting agents, etc etc.

For most piezo heads you target 10-12 cPs for viscosity at jetting temp.

To start with though i'm going to be doing just basic jetting for a while to test the compatibility of my ink. I also have some thoughts to make a DIY drop watcher but probably this isn't required.

In terms of my ink / application I might not talk about this very much sorry. Though all my ideas usually turn to dust i'm hoping it will become more than a hobby at some point. In like likely event my idea doesn't work, i'll definitely share it but it's a chemistry process thing that's probably not too interesting anyway for most people

Still I wanted to document my build of the printer side of things so others could replicate it in the future. It's so frustrating that there's such little inkjet info out there

[notsure]

I have been using LinuxCNC for motion control complex inkjet printers for many years. I can even control 5-axis systems.

1. What kind of controller are you trying to using in your printer for motion? How do you plan to sync the motion with jetting?

[chacha]

Are you still doing it? Do you have an E-mail address to contact you?

[picoj]

Sorry it's been a while, I am still working on this. I have managed to get basic printing working enough to print some test patterns. I am currently working on the FPGA system for taking images and then sending them to the printhead etc.

This project was significantly more complicated than I initially expected. I ended up having to buy 3 print heads. The first was for a Mimaki printer and had a non-standard connector. The second I bought used and arrived broken. Eventually I just bought a new one. Progress was also slowed when I got busy with work and other projects I am working on also.

Anyway i'm happy to share my experiences, just send me a private message and I can give you my email address. I can also post some photos of some parts of my setup if everyone is interested.

[chacha]

Sorry it's been a while, I am still working on this. I have managed to get basic printing working enough to print some test patterns. I am currently working on the FPGA system for taking images and then sending them to the printhead etc.

This project was significantly more complicated than I initially expected. I ended up having to buy 3 print heads. The first was for a Mimaki printer and had a non-standard connector. The second I bought used and arrived broken. Eventually I just bought a new one. Progress was also slowed when I got busy with work and other projects I am working on also.

Anyway i'm happy to share my experiences, just send me a private message and I can give you my email address. I can also post some photos of some parts of my setup if everyone is interested.

send you a private message,please check it