[tinyallotment]

Hi All

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

[clydesdaleclopper]

wow that looks fab 

[Rosemary]

I'm impressed 

[tinyallotment]

Thanks Guys

I am trying to do a little bit towards this each day or at least several times a week and as it is nice weather I thought I would make a start of the templates for the triangles.

There a two types of triangle that need to be made. One type makes pentagons and the other type makes hexagons. I need to make 30 pentagon triangles and 69 hexagon triangles so an accurate jig is essential.

You start by cutting one of each of the triangles from plywood. Then you clamp a piece of 2 by 1 along each edge basically making a finished triangle as it will go in the dome. Once you are happy with your shape you hen fix anther triangle of 2 by 1 inside your first triangle and screw and glue this inner triangle to the plywood. this is your jig.

I have cut the plywood but I am getting the first bundle of wood tomorrow so will try and get the jigs done then



paul

[stufe35]

I built one of these almost 30 years ago...I'll see if I can get some pics and post them.  Mine was from a ready made kit....and it was a nightmare !

[tinyallotment]

I would love to see pictures of it if you can find them.

Paul

[stufe35]

It was for a neighbour where I lived  as a child,  my sister still lives  there  ill see if she can get some pics as Im sure its still there !  I was 18 or so when I built it, my first summer back from university, I was paid £3 hour which was damn good money for a student in 1986/7 !

[tinyallotment]

Things are moving on now and it all seem a little less daunting.

I was expecting it to take about 10 minutes to make a triangle but I can do them a lot quicker than that and that was the first ones I have built and I haven't really got a system going yet.

It took me about 30 minutes to build 6 triangles and then assemble them into a hexagon panel.

This is fantastic as I was thinking it was going to take weeks to build a dome but if there is the two of us and we have a system I reckon we could do a dome from start to finish in a few days and a day installing.

Anyway. I am pleased with the potential speed at which I could build a dome if I had all the materials at hand. I have run out of screws now so have to knock it on the head but I am keeping a note of everything I need so when I am building future domes I will know I have all the materials and supplies on hand before we start.

I am getting excited now



paul

[Treud na Mara]

Soooo impressive 

[tinyallotment]

Why thank you.

Paul

[Caroline1]

Will definitely not look like anyone else's greenhouse. Looking forward to seeing final pictures

[tinyallotment]

As you have seen in the previous post I have completed the first of the Hexagon panels so the next step was to complete a Pentagon panel so I could be sure they would go together before forging on and making the rest of the triangles.
There are only 6 Pentagon panels to make and now I know they work and everything fits together and my two chop saws are set to the Pentagon angles I will press on over the next week or so and make all of the pent triangles.
Here is a picture of the two jigs needed for building this dome. The tall one is for Hex triangles, the other is for Pent triangles.



Making the triangles is simple once you have the templates built and checked for accuracy. You start by cutting the correct angles on one end of each of the struts. then you clamp the struts to the template and screw the struts to each other and saw the projecting ends off.
I will add a photo of this later.
As I am finishing each triangle and before I take it off the template I mark the apex of the triangle as this makes it fool proof when assembling the panels.
Here is a picture of the finished Hex and Pent panels before putting them together to test their fit.



You wouldn’t normally make the panels up like this before covering in plastic but as this is the first dome I have built I wanted to make sure everything lined up and the two panels fitted together.
Here is a picture of the Hex and Pent panels fitted together.



To give you an idea of the hight of the finished dome there is another Hex panel to go below the Hex panel in the above picture. The picture above does illustrate the curvature nicely.
So now I have to get stuck in to making all the rest of the triangles and covering them with plastic.
Ultimately there will be a detailed step by step article on the Geodesic Dome Page of this Blog
More soon
paul

[Rosemary]

Cannae wait to see it finished. No pressure, though 

[tinyallotment]

Thanks Rosemary

We have an open day at the allotment in about a months time and I aim to get it finished in time for that but it all depends on time, money and the weather.

paul

[Caroline1]

You should let gardeners world know, they were asking people to contact them with unusual things in their allotment so they could film and show later in the year