Date not cycling with addition of time

[Cummins]

Trying to figure out issue with adding date and time.
The code is listed below.
I have watched the code while running. The initial date FDateS and FDate(t) value is m/dd/yyyy (9/16/2010) and no time. FDateS has different amounts of time added to it. The issue I have encountered is that once it passes midnight, the date does not change but the time reflects the change to 00:00:00.

Public FDate(1000) As Date
Public FTime(1000) As Date


FDate(t) = CDate(Mid(FindData("sm_Sys_BatchOpenTime"), 1, 10))

For H1 = 1 To n
FDateS = FDate(H1)
For r =1 to 50
FDateS = CDate(FDateS) + CDate(FTime(r)-Ftime(r-1))
Next
Next

 

[Cummins]

Want to add some clarification...here is the output I am concerned with

9/16/2010 23:00
9/16/2010 23:30
9/16/2010 0:00
9/16/2010 0:30
9/16/2010 1:00
9/16/2010 1:30

It is as if the date is a string instead of a value.