Covering a 2v dome
Plan view of the full cover
The pentagons are shown complete to aid understanding of the component parts. As a flat pattern there would be a triangular gap between the edges of two of the triangles. Once joined together the pentagons would have their 3-dimensional form.
'Short' and 'Long' above represent the full point-to-point lengths, not the stick lengths that you have cut for your dome.
Just two triangles
The dome is made up of 30 x isosceles triangles and 10 x equilateral triangles.
30 x isosceles
10 x equilateral
Find out the triangle dimensions and total area for your diameter
Visit our dome calculator here, input your diameter at the top and then open the 'Covers' section below. This will show you the triangle dimensions for your diameter, and the total area.
The triangle sizes our calculator gives you are based on the skeleton of the dome (the line that runs through the middle of the sticks). So in practice the triangles may need to be a little bigger to accommodate the slight increase in diameter created by your sticks.
Consider any seam allowance you may require, which you'd need to add on to your triangle dimensions.
It's a good idea to take a template for the two triangles from your dome once it's built, to check sizes and to adjust as required based on how you're intending to attach the cover to the dome frame (eg. if making a greenhouse).
This is also a good way to find out the size of any additional triangles created as a result of an adaptation.
In time we hope to have a downloadable base pattern which you can work from.
For now here is a partial pattern that we used to make the inset partial cover shown below. This will give a bit of an idea how you can take the basic forms shown above and combine them to create bigger repeatable shapes to simplify construction.
There are also some DIY cover resources here.
The colour dots indicate points to be aligned. The stars indicate Long lengths. Remember when calculating covers to use the point-to-point distances, not the lengths that our calculator gives which relate to the lengths to cut your sticks to.
Cord is passed through loops at the points of the cover. These are tied into hanging eyelets on the reverse of the hubs. You can also use cable-ties which is quite a quick and secure way attach the cover.