I am toying with the idea of using an Arduino to drive a standard print cartrige of either piezo or thermal head.
I do not know what the drive requirements are though, anyone know ?
You need to post a link to the datasheet for the print head you plan to use.
This is not a trivial exercise and a 16MHz Arduino may not be capable of doing it.
...R
This is the nearest i can find.
https://assets.epson-europe.com/eu/precision-core/PrecisionCore_Fact-Sheet.pdf
The lack of technical information generally makes me think that it will be very difficult to come by.
EDIT
All i know is that the waveform shape is important and the waveform can vary from one drop to the next.
Jeez ... I had assumed you were contemplating something simple. I suspect the space shuttle is less complicated 
...R
PS. I had overlooked the fact that it was you asking the question when I wrote Reply #1 - sorry.
To start off with i was hoping to make something simple just to test salvaged heads for operation.
One of the patents here
http://patft.uspto.gov/netacgi/nph-Parser?Sect2=PTO1&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&d=PALL&RefSrch=yes&Query=PN%2F6758544
Sheds some light but not much.
I know someone on the net has done it as i came across it by accident once , he was using uv opaque ink for PCB's.g
EDIT
The head does not appear to have GND and supply either.
It seems to derive them from the rather odd drive signal.
All the circuitry required to drive the individual nozzles appears to be on the head though.
I was thinking that driving a thermal bubble jet printer may be easier although that limits me to water based inks, and i would need a drive circuit for each individual nozzle..
Not found much on drive requirements for those either.
The CLK signal is a very short pulse which may suply the ground reference although it could be the colour input data signals equally.
You won't be able to find any technical details on those print heads, as that would make it way too easy to make cheap compatible ones, and inkjet manufacturers don't want that to happen.
Very tough project this is going to be! Good luck.
Thanks , i suspect anyone here that knows would not be allowed to say anyway.
Annoying bit is i know someone has hacked them already but lost the link.
I don't know if this is relevant, but I found the InkShield.
Book.... Inkjet applications might be what you are looking for.
Very relevant , thank you.
I have a printer that uses those and a few old ones i can experiment with.
Considering it took HP several years to develop the first ink jet printer, you have a major task on your hands. In some of the print heads, the smarts are built into it. That is, a serial signal is sent and the head decodes the serial signal. That would be very difficult to reverse engineer. Even if you were able to do that, the shape wave form, in and of itself, is complex.
I like the idea of being able to do this, but it is not in the realm of the hobbyist.
OldSurferDude:
Considering it took HP several years to develop the first ink jet printer, you have a major task on your hands. In some of the print heads, the smarts are built into it. That is, a serial signal is sent and the head decodes the serial signal. That would be very difficult to reverse engineer. Even if you were able to do that, the shape wave form, in and of itself, is complex.I like the idea of being able to do this, but it is not in the realm of the hobbyist.
Many were tried before HP. But they ALWAYS left ink spatters around the character. HP was able to suck the ink back into the head right after is was jetted out and solved the problem.
In the 1980's I tested many low priced ink jet printers for a bank software company and all failed till HP found the fix.
Paul
Paul_KD7HB:
. HP was able to suck the ink back into the head right after is was jetted out and solved the problem.Paul
AFAIK suck back can only be done with piezo heads not bubblejet.
Unless the physical design of the head makes it possible.
Perhaps that is the reason for the strange waveform.
I have found the link i was looking for.
http://techref.massmind.org/techref/pcb/etch/custom-vs.htm
Unfortunatley he says that some of the code for the FPGA is proprietry so he cannot release it ?
So i am back to square one.
Was the HP you mentioned bubblejet ?
Perhaps it would be simpler to buy a cheap (used?) printer and modify the mechanical parts so they can handle PCBs rather than paper.
I think I have seen web pages about that.
...R
Yes i have seeen similar , there seems to be a lot of mechanical work required though.
I think it could be easier in the end than reverse engineering a modern one though.
I had an Epson R1800 printer (expensive) that had an adapter so it could print on CDs (never used the adapter). Maybe that facility is available on other printers.
Or what about the modern equivalent of a HP Plotter that draws with a pen?
...R
I have an Epson PX720 printer with a CD drawer, there was a hack somewhere that allowed it to print onto small PCB.
What i want is a printer that can print onto larger thick substrates generally.
Just noticed an epson for 49 in staples so maybe i will give it a try.
The reason I mentioned the CD drawer is because I suspect it may be easier to hack those mechanicals rather than a unit that only prints on paper.
I don't currently have a printer that can print on CDs so I can't look at the mechanism.
It would be interesting to experiment with a DIY baseplate driven fore and aft by a suitable motor with the upper part of the printer mechanism set on top of it.
I bought a cheap used printer (Canon, I think) in a charity shop hoping there would be a stepper motor in it - but there were just two very cheap DC motors. The clever part was the very fine encoders it was using. It may be possible to transfer the paper control encoder to a more powerful DC motor if that is needed to move the heavier PCB back and forth.
I am vaguely interested in this myself as a possibility for printing etch-resist onto brass for making parts for model trains.
What do you plan to use as "ink" ?
...R
Robin2:
The reason I mentioned the CD drawer is because I suspect it may be easier to hack those mechanicals rather than a unit that only prints on paper.It would be interesting to experiment with a DIY baseplate driven fore and aft by a suitable motor with the upper part of the printer mechanism set on top of it.
I bought a cheap used printer (Canon, I think) in a charity shop hoping there would be a stepper motor in it - but there were just two very cheap DC motors. The clever part was the very fine encoders it was using. It may be possible to transfer the paper control encoder to a more powerful DC motor if that is needed to move the heavier PCB back and forth.
I am vaguely interested in this myself as a possibility for printing etch-resist onto brass for making parts for model trains.
What do you plan to use as "ink" ?
...R
It is a good idea.
I purchased the printer because of that feature and the hacks on the net.
It was an expensive printer though , the driver for it is a bit flaky so for other reasons with other users complaining i am coming around to the idea of replacing and dismantling it.
There are various speciality inks available , example.
UV opaque inks can be found also.
They only work on EPSON though , not bubble jet.
Robin2:
I am vaguely interested in this myself as a possibility for printing etch-resist onto brass for making parts for model trains....R
I have done this with my printer.
With thin brass it fouls the head , it needs to be kept flat.
I printed onto photoresist then exposed.
Spray on stuff was useless but the proper Seno resist spun on works.
Epson black seems to work well , i believe that there are uv opaque inks available.
Etch resist inks is another ballgame , some have reported inks that work to varying degrees.
My feeling was to go with standard etch resist then print with UV opaque ink , not done the experiments yet though as i did not want to feed unknown ink though a fairly exspensive printer.
Printing on to this with uv opaque is something i have tried.
Previously Mega did a silver foil version which was excellent but Mitsubishi no longer make it.
Both suffer(d) from short shelf life.
That was in through hole days.
With surface mount the problem i find is in the solder resist layer the detail can be under 3 mic's which does not work well and i depend upon a dam to prevent bridging when soldering.
Eyesight ETC makes this stiff difficult.
With brass i find that spray etching gives a much cleaner result