An acceptable register is possible with sheets if you avoid the usual sheet loading where the head carriage sensors measure the overall sheet position. I use register tabs at the front of the Z3200 and load the sheet at an angle so get a warning that the sheet should be registered to the "blue line" which in my case are the tabs then. The sheet is then loaded correctly with the right side edge measured by the carriage optical sensor. Print the lightest image/text first. With 102x72 cm sheets, always keep the landscape sheet loading method so the 102 cm leading edge is against the register tabs. First side printed I measure the sheet's right edge to right side cutting mark and cut the sheet's left side at the same distance from the left side cutting mark. Flip the sheet over the length and the same long sheet side is brought against the tabs for the backside print. After a proof print like that the tabs are placed correctly for the sheet angle register.
In production of more sheets I usually change the image position on the print page to avoid the measuring and cutting of the left edge.
It sure is taking way too much time other than for proofing, exhbition samples or props creation. On the older Epson's this process went faster than on the Z3200.
On the Drupa I have seen Epson towers with one 9600 above and reversed to the one beneath and a ss ramp to guide the sheet into the one below. Color proofing work but not with good register.
Best method would be a printer with two head carriages opposite one another and the roll paper more or less free floating between the feeding roll at the underside and a winding unit above it. There are not that many dual sided qualities on roll right now but that might change then. I think the easiest lay-out for feeding the printer would be mirrored images for both sides so two double sided pages are created at the same time. Use a 60-65" width then. Another Drupa showed a printer like that for textile/banner/sign jobs. Ecosolvent type if I recall it correctly.
Met vriendelijke groet, Ernst
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