I am on a z3100- it does not slow down without a skewcheck, but i have larger margins ( so less space for printing) on my paper...
( i think because the printer is now not sure about the size...)
The printer is very strict and it may take some attempts till it finds you put the paper in correctly.
Now, if you have to print a 100 sheets that really ruins your day...
But the good thing is you can have really shallow margins and it comes out with straight borders.
( something that was very difficult in my darkroom days.)
When I received my Z3200 about 8 years ago I noticed that with Skew Check Off the printer became slow and remained slow when I switched the setting to Skew Check On. It got its "speed" again only after switching to Roll and then for both Skew Check On and Roll. I reported that to HP Barcelona and they admitted it as a bug but no remedy firmware followed. That bug I must have written about in 2009/2010.
The Z3100 got the Skew Check Off mode maybe a year after the printer was available so in 2007 and it does not have the issue as described, speed remains the same, just the paper insert is different.
For dual sided printing in register I often start printing from the roll and then with a precut on the roll leading edge right after the paper insert so the first printed sheet has the same leading edge as the rest that come after it. Add about 15mm extra for the print page size to create the right print margin at the trailing edge for sheet printing. Qimage image corner marks added in the print. First side done, I cut the left side that it has the same distance as the right side has to the Qimage corner marking (there has to be at least some mm extra white on the left in the first print run). Frugal ink image like text preferably printed first as there will be less smudging and the paper will keep its dimensions better. I then insert the printed sheets turned over (leading edge still leading edge)
but at an angle so the printer directly says I have to use the blue line for register. On that blue line I use tabs to register the leading edge against. On the left right register the sensor on the head of the Z should give the same distance it did in the first run. After one or two prints I have the skew between front and backside register in control.
The Skew Check Off mode was intended to allow paper with deckle edges. For register it is working out worse anyway, not just on the printing speed. I print deckle edge sheets on the Z3100 when needed but it happens seldom.
Met vriendelijke groet, Ernst
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