Measure Your Blowing Force

Here's a simple way to measure how hard you blow. You'll lift a weight by blowing into your boat's sail. Once you know how hard you can blow, you can use this setup to practice blowing to increase your capacity and power!

Materials

• 3 or 4 Large books (like phone books)
• 2 Foot of string
• Small plastic container or lid (photo film box)
• Adhesive tape
• 1 Flat bottom regatta boat or sail rig
• Small weights or a few ounces of clay or water
• 6 to 10 round pencils (like a set of color pencils) all the same size
• Weight scale

Setup

1. Cut three 3 inch pieces of string and tape them to the container evenly spaced around the rim
2. Tie the three strings together and to the longer peice of string so the container is suspended level
3. Stack the books on a table top with room in front of the books
4. Place the container in front of the books with the string laid over the books and pulled tight
5. Place the boat on the pencils so it rolls smoothly in the middle of the top book in the direction of the string
6. Tape the string to the rear bottom of the boat or sail rig and cut off the extra

Measurements

1. In front of the books, on top of the weight scale, fill the container with enough weight to make an ounce.
2. Place the container back in front of the books.
3. With string tight, blow into the boat sail trying to pick up the weight.
4. If the weight lifts up, add half an ounce to the container and try again.
5. When weight can no longer be lifted, take a little out and blow again.
6. You have found the most weight you can lift when a small amount more can not be lifted. The maximum weight you lifted is the most breath force you can muster. The weight of that small amount is an upper bound on your measurement error.

An adult may blow with a force of about 1 and a half ounces. Children vary wildly.