Kash, Madhan and Sevan zigzagged their way across Ealing borough from their first task of the day near Sudbury to Wolf Fields Urban Nature Reserve in Norwood Green. They were looking forward to seeing an Anderson shelter for the first time, imagining that it would be a large, sturdy structure designed to withstand nearby explosions. What they found at Wolf Fields was a bit larger than a play house and felt a bit flimsy for its original purpose, but that didn't make the task any less interesting or rewarding.

The session started off by lifting the shelter out of the nettle patch that it'd been helpfully left in. It was surprisingly light and easy to carry with a handle on each corner. Even after 80-odd years, it was still reasonably sturdy and not in bad condition. The metal sheeting was torn and dented in places and the frame had rusted. Its state was quite impressive given that it probably lived outside for all of that time.

The site manager Andrew explained that the shelter would have been placed below ground level with only a few centimetres below the roofline visible. It was the soil around the shelter that gave the protection, so the thin steel was only really needed to keep the earth from getting in.

After seeing the shelter, we went on a hunt for suitable tools. This was the first time that any of the GoodGymers or Andrew had tried to repair a metal shelter. Hunting around the site container, they dug out some brushes to remove dirt from it, some sponges, a bucket and a few pieces of roofing felt to scrub away at the rust. We wanted to prepare it for a first coat of paint to protect it from the elements and start to make it look like a well concealed bird hide.

We started by wiping the accumulated grime off the outside of the shelter, using brushes or wet sponges for the panels. It was hard to tell which decade the spider webs and dirt inside were from. Regardless, they were swept away too. The roofing felt we'd found was used to clear the rust from the arched frame at both ends of the shelter. This needed some muscle and a lot of persistence, with Andrew eventually finding us some coarse sandpaper which did a better job. With 4 of us all sanding, the motion meant the shed was a-rocking and Kash provided some tunes to keep us all motivated.

After 90 minutes, we were covered in rust dust and had achieved as much as we could with cleaning. By no means did it look new as it still had some gashes in the panels and inside, the benches hadn't been touched and still needed to be repaired. Still, we were ready for the next step.

Another rummage in the tool container produced 2 tins of paint (green and red), 2 paint rollers and a large fence painting brush. We had a discussion about the designer's vision for the shed and how to make it look inconspicuous to the birds yet also colourful enough to promote A Rocha, LAGER Can and GoodGym. The plan changed a few times before finally landing on "mostly green, with a red frame and some newly discovered blue paint on the side with the door"

With the time we had left, we used the paint rollers to turn one end panel green, which was easy and the frame on one end red. We then tackled the more difficult corrugated body. The rollers were a bit too big for the grooves, so we had to develop a rocking motion to get good coverage on the sides. We were able to paint one more side green before we ran out of both paint and time.

We left feeling really happy with our afternoon's work and we'll definitely be back to finish the job once more paint has been sourced.