One way to look at gift wrapping is as the art of making three dimensional objects beautiful. Given a choice, I would always wrap a rectangular prism with its neat edges and hospital grade folds, but I have to admit to a soft spot for the cylinder. A cylinder is more challenging to wrap and certainly very challenging to wrap if you have to do many at speed.. but it is for me one of the most alluring basic curvilinear geometric shapes.
We all know the cylinder is a closed solid that has two parallel (usually circular) bases connected by a curved surface. Let’s look at the vital statistics:
- number of faces 2
- shapes with similar faces -the cone
- base shape – circle.
- The bases are congruent and parallel to each other
- volume π × r² × h
- surface area 2 × π × r × (r + h)
According to OpenMath, when the two bases are exactly over each other and the axis is a right angle to the base, you have a right cylinder.If one base is displaced sideways, the axis is not at right angles to the bases and the result is called an oblique cylinder. The bases, although not directly over each other, are still parallel. Did not know that and need to find a way to get that in conversation!!
|Right Cylinder||Oblique Cylinder|
A shape which has a circle as a base is the most familiar and usually what people mean when they say cylinder. But the bases can be almost any curved shape, such as an ellipse. In this case the resultant shape would then be called an ‘elliptical cylinder’.
So many possibilities…and just as well because there are so many cylinders to wrap – jams, relishes, preserved fruits, candles, cans, biscuit tins, rolls of tape, spools of ribbon, yo-yos, lipsticks, chalk, water bottles, pencil holders, presentation boxes of bone china, tyres, cups, tupperware containers, a telescope…how about a punching bag?
I like to wrap a cylinder by placing by rolling paper around the shape and then pleating the two bases. The pleat does take a little bit of practise…but once you have triumphed with one, you will never go back. The amount of paper at each base should go half way across the base. You start by folding the paper to the mid point of the base and then bring the paper in to the mid point in small increments.
One of the best videos is from Wrapology and I recommend you take a little peak. One word of warning – you can can get a lovely look wrapping the cylinder with pleated bases – but do not try either a. in a hurry or b. with your most beautiful paper first off. Grab that can of tomatoes out of the cupboard and have a little go with my friend the cylinder well in advance.