Post by swanrail on Apr 5, 2008 22:40:48 GMT 1
In issue 58 you are asked to set up the small control post so that the ladder is 120 degrees from the downpipe.
If like me, the last time you saw a compass, protactor or any other menas of measuring angles was many moons ago (and have no access to children either!), then this is how to set up the angle:
Take the piece 217 as mentioned on picture 08.
Find the centre point. Mine measures 57mm end to end, so I used 28.5mm for the centre. Width between the parallel edges is 14mm, so the centre point lies 7mm from one edge.
Next, draw in the centre line, as per the dotted line in pic 08.
120 degrees means that A in the pic. is 30 degrees below the centre line. Sine of the angle 30 degrees is 0.5, which means that the drop from the centreline (7mm) divided by the long side from the centre point to point A equals 0.5. Therefore, with simple maths, the long side must be 14mm long.
Using a ruler, and measuring from the centre point so that the 14mm measurement on the ruler just touches the outside edge of part 217, mark point A.
Use the same technique to mark in point B.
You now have the template as shown in pic 08 of issue 58!!!
To centre the plastic part:
This also happens to be 14mm in diameter.
Mark two points 7mm either side of the centre point, and drop perpendiculars to the edges.
Place the plastic part on 217 so that it lies centred so that each pencil mark either side can just be seen as well as both edges.
If like me, the last time you saw a compass, protactor or any other menas of measuring angles was many moons ago (and have no access to children either!), then this is how to set up the angle:
Take the piece 217 as mentioned on picture 08.
Find the centre point. Mine measures 57mm end to end, so I used 28.5mm for the centre. Width between the parallel edges is 14mm, so the centre point lies 7mm from one edge.
Next, draw in the centre line, as per the dotted line in pic 08.
120 degrees means that A in the pic. is 30 degrees below the centre line. Sine of the angle 30 degrees is 0.5, which means that the drop from the centreline (7mm) divided by the long side from the centre point to point A equals 0.5. Therefore, with simple maths, the long side must be 14mm long.
Using a ruler, and measuring from the centre point so that the 14mm measurement on the ruler just touches the outside edge of part 217, mark point A.
Use the same technique to mark in point B.
You now have the template as shown in pic 08 of issue 58!!!
To centre the plastic part:
This also happens to be 14mm in diameter.
Mark two points 7mm either side of the centre point, and drop perpendiculars to the edges.
Place the plastic part on 217 so that it lies centred so that each pencil mark either side can just be seen as well as both edges.