It would help if you would tell us what OS you are using (so we know what the underlying windowing system is) and what verssion of Tk you have. Also, a small program to demonstarte the problem would help: I do not have a database with the right data in it to test this program. If you could do a simple Tk program that shows the problem, it would sure help.

I have heard of problems with some graphics libraries drawing incomplete circles when told to draw 360 degrees, but I think this is a different problem.

--traveler