How to Make a Compass Using a Pencil and a String

Written by ehow contributor
  • Share
  • Tweet
  • Share
  • Email

You can make a simple "makeshift" compass using nothing but a piece of string, a pencil and a thumbtack.

Skill level:
Easy

Other People Are Reading

Things you need

  • Piece of string longer than the diameter of the circle you want to draw
  • Pencil
  • Thumbtack ("push pins" work very well)
  • Paper, or whatever you want to draw your circle on
  • Ruler to check the size of your circle (if it needs to be an exact size)

Show MoreHide

Instructions

  1. 1

    Determine how large you want your circle to be. Cut a piece of string that is about 8 inches longer than the diameter of your circle.

  2. 2

    Tie a slipknot on both ends of the string. Make sure the distance between the knots is half as long as the total distance across your circle. The distance between the knots will be the radius (half the diameter) of your circle.

  3. 3

    Secure the pencil in the slipknot on one end of the string.

    How to Make a Compass Using a Pencil and a String
  4. 4

    Secure the thumbtack in the slipknot on the other end of the string.

    How to Make a Compass Using a Pencil and a String
  5. 5

    Place the tack on the very center of where you want your circle. You do not need to push the tack into anything. The sharp point on the tack will keep it from slipping with just with a small amount of pressure applied.

  6. 6

    Hold the tack while pulling the pencil out to make the string tight. If the size of your circle needs to be exact, make a mark with the pencil and then use a ruler to measure the distance between the center dot and the mark you just made. Make any adjustments necessary in the length of the string.

    How to Make a Compass Using a Pencil and a String
  7. 7

    Draw the circle with the pencil, keeping the string tight at all times and the pencil straight up and down. (Tilting the pencil different ways while drawing will make the circle slightly imperfect in places.)

Tips and warnings

  • You can use this basic method to make very large circles, even 100 feet in diameter. Just use a thin rope instead of string and a thin tent stake or sharpened dowel rod instead of a thumbtack. Replace the pencil with whatever will work best on the surface you are working on. (Try chalk for pavement and sprinkled lime or spray paint for grass.)

Don't Miss

Filter:
  • All types
  • Articles
  • Slideshows
  • Videos
Sort:
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the eHow.co.uk site, you consent to the use of cookies. For more information, please see our Cookie policy.