An issue I've never seen before, 'truncated' X  

An issue I've never seen before, 'truncated' X

Here's one from the Go Figure Department.

As part of my current project, I need a bracket that is almost as wide as the I3 build plate, or just slightly smaller than 250mm.

I swear I've done prints that use almost the entire X space before, and I've never seen anything like this.

The print centers fine and slices fine.

I did have to turn off the skirt to get it to slice without errors, but NBD, I've had to do that before.

When it printed, however, the first thing I noticed was the corners on the left (right in the photo below) side of the print looked square and not rounded.

Looking closer (you may have to expand the image to see these details) there's some visible artifact along with the truncation.

Out of curiosity, I started the print again and watched the outline of the first layer go down.  There was no evidence at all of it hitting any kind of 'hard stop' or physical barrier at the left side of the print.  It just appeared to draw the outline as expected, but with rounded corners on the right, and square corners on the left.

I then re-sliced with the model positioned catty-wumpus (for lack of a better term) on the build plate to give it a bit of breathing room.

I watched it print the (now allowed) skirt and the outline of the first layer, and it printed as expected, with round corners on the left and right side.

The print finished as expected, with round corners on all four sides, and no raggedy artifacts.

Has anyone else seen this?  I am aware that I may be pushing things, but I could swear that I've done prints coming close to the full X width before and never noticed this.

This was with RepRappers ABS, all default (generic ABS) settings.