Inserting scale bars (Maritime Charting)
The Insert Scale Bar tool can be used to quickly and efficiently add up to three common nautical scale bars: Meters, Yards, and Nautical Miles. At map scales less than and equal to 1:10,000, two scale bars are drawn: Yards and Meters. At map scales greater than and equal to 1:10,001, three scale bars are drawn: Yards, Meters, and Nautical Miles. You must be in layout view, with the data frame properties set (proper coordinate system, scale, and reference scale).
- Start ArcMap.
- If necessary, click View > Layout View to switch to layout view.
- 
 If necessary, add the Insert Scale Bar command by doing the following:
- On the main menu, click  Customize > Customize Mode.The Customize dialog box appears. 
- Click the Commands tab.
- Choose Nautical Cartography in the Categories list.
- Drag the Insert Scale Bar command to a toolbar.
- Click Close.
 
- On the main menu, click  Customize > Customize Mode.
- Click the Insert  Scale Bar button  . .The Yards and Meters scale bars are inserted if the map scale is less than or equal to 1:10,000. The Yards, Meters, and Nautical Miles scale bars are inserted if the map scale is greater than or equal to 1:10,001. 
- Reposition the scale bars as needed. Sugerencia: Sugerencia:You can increase or decrease scale bar division values by stretching or shrinking the scale bar element.