I have actually started work on building my Geodesic Dome greenhouse for the allotment. I have been talking about it for years and waiting until I had enough money to buy all the materials etc but to be honest I am never going to get it built if I wait until everything is in place so I have decided to just start building it anyway.
When it is finished it will look like this

We have built the base this weekend. The base is quite complicated. There are 15 base boards made up of three different types. Each of the base boards need to have a 12º angle at each end and along its top edge. 5 of the board also have to slope to the right and 5 to the left.
A couple of days ago I bought the wood and cut all the boards to length with the right angles on the ends. Then I set about cutting the tapers with the 12º angle along the top edge. I did this on the table saw by setting the blade at a 12º angle and setting the depth so it just cut through the board. I then used another board on top of the one being cut, offset by 32mm to give me the correct taper (I hope)

All the boards cut

I cleared the ground of grass and weeds and started fitting the base boards yesterday. Using a stake in the centre of the dome as a datum point for both level and radius it was not too difficult to assemble the base although I will need to tweak it a little when I have an extra pair of hands

Now we need to start making the jigs for making the 103 triangles that make up thee dome. We will make triangles as and when we can afford the materials but I hope to have the dome made by the end of the summer.
I will keep you posted
paul