I found the instruction on how to make wine glass candle lampshades neat, but I don’t have to rely on pre-made templates any more, because I know how to construct a cone ;-))
That’s exactly what I’ve done, additionally I didn’t use no wine glass but a water glass.
Admittedly a wine glass would look better, because the tea light is hidden then.
Or I should cover the lower part of the water glass.
Or I should make the cone higher (and I can ;-)).
I made my lampshade from sandwich paper which is actually too fine and doesn’t hold the shape (in the instruction they are using vellum). To improve this I taped some clear tape against the paper from the inside.
But it didn’t help very much.
Before I cut the lampshade I embellished it with some flourishes – looks cute, doesn’t it?
This is my cone calculation (shortened version):
Desired data:
Height H = 6 cm
Upper radius Rt = 3 cm
Lower radius Rb = 5 cm
Calculation:
PQ = Rt * H / (Rb – Rt) = 9
QT = 3
PT = sqrt(81 + 9) = 9,5
PR = 15
RS = 5
PS = sqrt(225 + 25) = 15,8
That is:
Outer radius = 15,8 cm
Inner radius = 9,5 cm
a = 360 * (1 – ((2 * Pi * Rb) / (2 * Pi * PS))) = 360 * (1 – (31,4 / 94,8) ˜ 241°
Great, isn’t it? ;-)
As you can also see on the topmost photo, another advantage of self-calculation is that the upper rim of the lampshade barely protrude over the rim of the glass and therefore the danger of fire is reduced.
Anyhow: Always be careful!
;-)
Links:
Wine Glass Candle Lampshades
Here at unikatissima: Calculation of a cone on the basis of the desired height, desired upper and lower diameter