this is copy of my reply to post by:CadMonkeyJon under ACAD2012 forum: Well,
More than nine months later and new revision (ACAD13) and it is still not fixed.
Just found the same issue with my AC2013.
A bit of difference is that the polylines do not have to be even closed. Any polyline gives me exactly the described behaviour, which is definitely not intended.
Appears still not resolved.
Does anyone know if there is any fix to this issue available by now?
Original message by CadMonkeyJon was posted under ACAD2012 forum; below is its copy:
Perpendicular Osnap not working correctly with closed polylines grips
490 Views, 7 Replies
I'm finding that when I try to drag a closed polyline to be perpendicular to a line, it wants to snap to the next vertex instead (see attached jpg which explains it better than I can!). It tends to only happen if the line I want to be perpendicular to doesn't extend to the perpendicular of the vertex I want to move.
I've only had this issue with AutoCAD 2012 and not with any previous issue. Anyone else had this issue?
I have the same issue but not all af the time. I have raised a number of support requests but always get palmed off and no solution has emerged.
The work around I have to use is having both perpendicular switched off in the osnap settings and whenever I want a perpendicular snap I have to select it with the control-right click shortcut menu.
As this is such an intermittent problem it seems to be very low on the Autodesk list to fix.
Sorry I have been of so little help but you are not alone
The work around is to hit TAB until you get the perp you are after, or use stretch command rather than grip edit.
I talked to our development team and got an answer this is as designed behavior.
Please check this help document.
Deferred Perpendicular snap mode is automatically turned on when the object you are drawing requires that you complete more than one perpendicular snap. You can use an object such as a line, arc, circle, polyline, ray, xline, multiline, or 3D solid edge as an object from which to draw a perpendicular line. You can use Deferred Perpendicular to draw perpendicular lines between such objects. When the aperture box passes over a Deferred Perpendicular snap point, an AutoSnap™ tooltip and marker are displayed.
But apparently many users including you have a hard time, so I will raised this issue to the wishlist.