More solar panels and some jigging…

This week the solar hot water panels went up on the basecamp roof. We are using flat plate collectors, you can see them waiting to be installed here.

The green technology we are putting in is in many ways one of the most exciting parts of this project. In the past our carbon footprint at Swan Barn Farm has not been anything to be proud of, but that is all changing this year, this is the latest step in that process.

The panels are fitted to bars which attach to brackets that reach through the tiles on the basecamp roof and attach to the rafters. Martyn the local bat worker has been present for the instalation of both these and the pv panels, we owe him a big thankyou for helping us with the work and ensuring that any disturbance to the roof didn’t cause any problems for the local bat population.

Flat plate collectors look a bit like massive iphones when they are strapped onto the roof, I guess there are a few arguments out there about the asthetics of this, but they are hidden on the back of the basecamp roof and I think they are a realy usefull piece of green technology.

They work by collecting the suns energy and focusing it on a pipe run which has an anti freeze solution within it. This solution passes along a pipe and into the bascamp plant room where the heat is exchanged inside a cylinder to heat the domestic hot water supply. On days when the sun is not providing enough heat the bring the water up to temperature the system will be boosted by a feed from the biomass boiler which we will be installing later in the year.

With the basecamp sleeping up to 19 people and 3 people in the new building you can imagine that there is quite a demand for hot water, especially after a hard days work in the woods. Our solar and biomass systems have been scaled to cope with this demand, and it will be a proud moment when they are switched on and we go over to using entirely sustainable sources of heat and hot water.

Meanwhile we have also had another working holiday helping with the project over the past week. The main job has been shingle making, and they have done a great job for us, making over 800 of them. Its not long untill we start the job of putting them on the roof, so its been crucial to get enough of them in stock to ensure first half of the roof can be completed in one go. Thanks guys, great work.
Before they go on the roof they all need to have a hole predrilled in them to ensure the nail that holds them in place doesn’t split the shingle in half. The holes need to be positioned accurately to ensure the shingles sit in nice level rows, this is where the jig comes in.

We made a jig (it makes sure each hole is exactly the same distance from the bottom of the shingle) and attached it to the pillar drill. Then it is a question of putting each of the 7500 or so shingles we need for the first part of the roof onto the jig and drilling the hole.

The volunteers made an excellent start on this, getting several wheelbarrow loads done. There is still a long way to go though, just another job to add to the list of stuff to do.

Pegs and wedges

The sweet chestnut frame of our building is being held together using oak pegs and wedges. The oak for them came from the coppicing work we do at Swan Barn Farm, if you get chance over the next couple of weeks I would really recomend taking a walk through the woods on the farm, the bluebells are at their peak, and if you get chance to visit early in the early morning the dawn chorus is an an avian assault on the ears. The coppicng creates ideal conditions for wildlife, and at this time of year you can realy see the response.

Wooden pegs are the traditional method of holding timber joints together, but a roundwood frame requires a slightly different technique to traditional draw pegs. The oak for the pegs was sawn on our mill back in february on a very rainy day.

It seems a long time ago now all that mud has turned to dust. We used a tree that had been felled two years previously and have been seasoning them further for the past few months. The idea being that the green wood of the frame will shrink onto the seasoned pegs over time and lock them in tight.

The pegs are cut to length and then the corners of the square blank are shaved off with a drawknife. After this a rounding plane is used to create the peg. Its a sort of giant pencil sharpener, you wind it around by hand and it shaves off the excess working its way down the wood to create the peg.

There is something quite satisfying about making something round out of something that was square. The frame requires quite a lot of pegs, another job for our hard working groups of volunteers.

The wedges are being made out of a couple of planks that have been seasoning nicely in our woodshed for the past couple of years. I spent an hour or so in the workshop making them the other day. It was done using our small circular saw.

I cut a small rectangle out of the plank and then set the saw at a slight angle. Flipping the rectangle over each time a cut was done made lots of small wedges all of (roughly!) the same angle.

After the joints have been cut in the two pieces of timber they are held together using ratchet straps. A hole is then drilled through the two timbers.

The peg is then knocked through the hole and a small saw cut is put in either end of it into which the wedge can be driven.

The wedge expands the end of the peg and holds it firmly in place. The wedge is left slightly proud in case it needs to be knocked in a little further as everything seasons and dries out.

The second frame is on the framing bed and is just about finished, we will be moving it onto its padstones tomorrow. Everything should be ready for next thursdays frame raising on time (touch wood!). I am really looking forward to seeing the first phase of everyones hard work coming together, hopefully it will be a proud day.