Mart, there is a non printable margin that the printer requires for sheets that you are not taking into account.
The new APS 1.20 is limited only to rolls when using the largest 9.18 target, and that is unfortunate. And not necessary.
Your response on margins doesn't correspond to how the APS actually prints with the largest TC 9.18 target (17 5/8" by 18 5/8" in size).
With the current APS, it leaves a 3/8" margin on the edge of the paper when it prints on 24" rolls.
I based my posting on the actual margin now left by the APS -- 3/8".
My calculations demonstrate that there is more than enough room for any non printable or printable margins. There is simply lots of room left on the 22" dimension for a 17x22 sheet.
And that is true even if the margin has to be greater than 3/8".
With a 1/2" margin, if the target is 16" wide on a 17" wide paper -- the 9.18 target would be about 20 1/4" long, leaving ample room for margins on the long dimension.
That means that the margins can even be slightly larger than 1/2" and the target would still fit on a 17x22 sheet. (Again, the actual margin is 3/8" with the current version of the APS)
* Again, the new APS 1.20 is limited only to rolls when using the largest target, and that is the reason that most owners of the Z3100 would buy it. Let's just be honest in how we all describe it.
* It is a major improvement that it works with 17" rolls.
* But it is a significant limitation that it doesn't work with 17x22 sheets -- since that is a widely used sheet size for those who may not buy rolls.
And that limitation is not explained by the actual margins utilized by the current version of APS 1.0.