Changing this code

I wanted to know if this was right,
Dim rCell As Range
For Each rCell In Range( _
Range("f1:f1"), _
Cells(Rows.Count, "e").End(xlUp))
If rCell.Value <> "" Then
rCell.FormulaR1C1 = "=(RC[-1] -INT(RC[-1]))*24"
End If
Next rCell
When I run it it takes the info and sets it to zero. I need it to take the
time in a1 and convert it to military time in b1, could someone please help
me out, Thanks Neal.