This is JUST A THOUGHT i have been meddling with for a couple of years. Haven't really researched on this, but might be possible - and might even be very easy! I don't know.

My thought is, simply, to modify an existing inkjet (office type) making it wider and perhaps fitting a CIS system on it.

Would it be possible just to "enlarge" the sideways movement by putting in a longer brushed iron bar and a longer gear belt? Of course the driver (and possibly the firmware?) would need to know to print wider.

I disassembled one of my own printers and found out, there is a sensoe registering when the printhead i in either side of the printable area. Also, there is a paper sensor. Much more than this, I don't know.

Anyone up for the challenge?