See Saw

The original design for this see saw came from a book by John Thurman published in 1956. He suggested building it in a pond or stream so that the Scout on the lower end of the plank went underwater. He says It is rather obvious to remind you that for complete success the two participants need to be of reasonably similar weight. If you forget this you may find you have drowned all your older Scouts. I know there are some in favour of that but I cannot advocate it as a general policy.

Equipment


- 4 x 4m (12 ft) spars
- 2 x 2m (6 ft) spars
- 5 x 1m (3 ft) spars
- 1 x 2m (6 ft) heavy spar or log
- 1 x 4 m (12 ft) or longer plank
- 16 x 8m lashings
- 4 x 8m guy ropes
- 1 x 16m lashing

Method

Prepare two similar A frames using the 4m and 2m spars and standard length (8m) lashings.

These two A frames will be lashed together using the 1m spars. The distance they are apart depends on the size of the log which must have room to pivot freely but should not move around sideways.

With one of the A frames horizontal, lash the 1m spars so that they stand vertically one in the apex and two about a metre up from the butts of the 4m spars on either side. Using the log as a measure, lash the final two 1m spars an appropriate distance along the 4m spars. (diagram A)

Lash the second A frame to the 1m spars, taking care to ensure that they are parallel and that the log fits snugly between them.

Attach 4 guys to the apex of the A frames.

Stand the frames up and peg out the guys.

At this point double check the lashings on the spars which will support the log there will be a considerable strain on them. Place the log in position and, using the long lashing length, lash the plank in position.

We suggest that old car tyres will make an ideal stop for each end of the plank, to prevent fingers and feet being crushed between the ground and the plank and to minimise jarring as the plank hits the ground.