Issues printing 8.5 x 11 borderless on 17" roll paper

[Kamilla]

I am trying to print two US letter size images side by side on 17" roll paper and using Lightroom to do it as I hate the Photoshop Plugin from Canon. I am using my new Canon ImagePROGRAF IPF6400S and 17" roll Kodak satin paper.

However, when I use custom package in Lightroom and set the paper target size to 11 x 17" borderless, it leaves a margin on the top and bottom in the amount of .25." (see attached) I understand there is overspray to do borderless, but why only on the top and bottom. I tried printing it but the image was shrunk to make sure the white margin remained on the top and bottom. When I make it fill the template, the center is not exactly 8.5." I assume there's a much easier way to do this but I just haven't found it. Please help me!

Thanks.

 

[PricelineNegotiator]

Kill it with fire.

Go to 12" paper.

 

[Kamilla]

12" paper? I don't see that Kodak carries 12" rolls. I've only seen 10" rolls. I wish I could just use US letter sheets, but for some reason my printer can't do borderless on single sheets... it's dumb.