Danial Riddle forwarded me this link https://stackoverflow.com/questions/7638458/converting-a-string-to-a-number where I noticed this note.  I had forgotten the limited range for an integer.  Clng conversion worked as expected for me.

To avoid potential hard errors in case the value is not numeric, I would first evaluate if the text is numeric by using the IsNumeric function.

If IsNumeric(textfield) Then
    numericfield = CLng(textfield)
End If