How to size thumbnail and arrow buttons in Scrollbar in a dbgrid


I am writting a touch screen app using Delphi 4.  When writting
the app I must make sure all buttons,etc are large enough on
the screen  for the user to touch.  I am able to lay the screens
out so that this is all possible.
My problem is that I need to increase the size of the scrollbar
in my dbgrids so that the user can touch the up and down
buttons as well as the scroll thumbnail.  How can I set the size of
the thumbnail,the up and down buttons, width, and height of the scrollbar
within the dbgrid.



When writing the application I must be sure that all buttons,etc
are big enough for a user to touch on a screen.  I have been
able to lay the screens out so that I can make the buttons,etc
large enough.