Non-Gardener builds an Observatory, Garden Railway and even Dabbles with Plants!

12th May 2022

The spoil heap from all the digging and clearing was 23 feet long, 2 to 3 feet high and about 5 feet wide! This would go to levelling the ground, further down the garden.

With the concrete dry in the bottom of both holes, I began laying blockwork. It was hard work laying the blocks so deep in the hole and I had to climb into the hole for the first layer, being careful not to stab myself on the rebars. Layer two was easier, but still quite a reach to lower the blocks in place without following them into the hole!



It took about 90 minutes to get the first twelve blocks in place. The first 180Kg of the foundation. Even though I laid the second pier foundation the evening before, it was firm by late morning today. I hadn't expected it to have cured, but it gave me the opportunity to get the blockwork in for the second pier.



Another 90 minutes passed and the second one was done. The blockwork needed to fully dry before I could pour the concrete inside and out, but I also needed to wait for some more rebar coming in the post. Local stores were all out of stock, so I had to go online.

The new rebars would be set into the top of the foundation block, then extend up into the pier. The existing bars would extend six to eight inches into the bottom of the pier. The foundation concrete would need to set enough to support the upper rebars and also be firm enough to support the weight of the concrete when the pier was poured.

 

13th May 2022

On Friday morning, the eight extra rebars I ordered, turned up in the post. I wasn't expecting them until Monday. Unlike the bars from B&Q which were varnished, these weren't and were covered in light surface rust. I didn't want to stick them in my concrete going rusty, so cleaned them all up with a rotary wire brush in the pillar drill and then painted them in Hammerite.

Since I was almost in a position to pour the piers, I made these wooden supports to hold the rebars straight in the hole while the concrete was poured. The lower cross holds the bars in the base of the pier while the second cross supports the bottom of the rebars that extend up into the pier.



The cross also fits the top of the pier tube, so when I come to pour that, I can also keep the bars straight. I only need one cross in the top of the tube as there's only four bars that extend up to the top.

 

14th May 2022

On Saturday, the floor joists were carried out once again to check on the height between floor level and the top of the pier foundations. I needed about 12 inches. The deep sky pier was pretty much spot on, with about 10 inches to the top of the joist, plus another 2 inches of the shed floor.



The solar system pier was a bit low by around a couple of inches. The easiest way to solve this was to add a layer of block paving bricks. So off to B&Q for eight bricks and a bag of sand and then back home to get them laid. This would allow the foundation concrete to be filled flush with the top, so the pier tube would start at the correct height.



My daughter gave me a hand out with one of the observatory end panels to check the pier heights against the rolling roof height. The piers were standing about an inch high, due to sitting on planks over the foundation holes. Allowing for the height of the pier adapter and mount, it should bring the telescopes into the roof cavity space, right where I wanted them.

 

17th May 2022

Rain delayed things a couple of days, but I was back out on the 17th. I added 80Kg of concrete around the outside of the blockwork on the first pier and then filled the inside level with the top of the bricks. The upper four rebars were added and left to set. Another 80Kg of concrete was added to the outside of the blockwork on the second pier.



18th May 2022

The following day, the concrete had set enough to work with. The wooden formers were removed first, leaving the eight rebars free to accept the pier tube.

 

The pier tube added next and the bottom edge was sealed with clay. Then concrete mixing began. A wooden cross clamped the top of the tube and was secured with guy ropes and stakes in the ground. This kept the tube stable while I tipped in and packed down the concrete.



I put the wooden rebar former inside the top of the tube while filling it, to keep the rebars in the correct position. Once around three quarters full, they weren't going to move, so it was removed to allow the tube to be filled to the top.

It was a little awkward tipping the concrete in around the crosses, as was smoothing off the top, but it seemed an easy way of make sure there were no accidents.

 

After lunch, the foundation of the second pier was filled with concrete and the upper rebars supported to allow it to cure overnight.



19th May 2022

That was set on the 19th and the second pier was poured. After the second pier was poured, I used the mixer to make a slurry of clay and soil, which was then used to back fill the remaining space around the pier foundations.

 

Amazing work @ArmyAirForce !
Your workshop looks great - we ended up extending our garage for my late husband to have a workshop for his model aircraft (jets).
I don't know if his posts are still accessible but a late forum admin @ARMANDII had a wonderful observatory with some serious telescopes.

 

Yes, I saw that thread.

 

21st May 2022

I began to attach the remaining legs, drilling the fixing plates to the concrete pads, but these were removed again for the next step. I also cut the tree stumps flush with the ground and removed the remaining plant life from under the observatory area.



The legs were removed in order to fit the weed membrane. That was spread out so it could be measured for the pier holes to be cut. There was lots of measuring before I committed to holes!

 

Once lowered down over the piers, the holes were sealed against the piers with several layers of duct tape. Then I started poking holes through the membrane so I could bolt the legs down.



When the legs were all in place, it was time to screw together the floor joists for the last time.



The two intermediate joists were cut next and screwed in place at the one third and two thirds positions along the floor. The bottom edges had already been painted in bitumen. I used a bar of soap on the 6 inch long screw threads to lubricate them, to help them screw all the way in with less effort. Once in place, the rest of the joist was painted. Two rubble sacks were placed over the piers to keep rain off until I had a roof to protect them.

 

22nd May 2022

The concrete hardstanding had been laid almost a month, so we felt that it was now cured enough to take the weight of my trailer. However, the shed was in the way of where I wanted my trailer. Time to move the shed!

This was no easy job and it took ages just to empty the shed of a whole range of garden and non-garden stuff. Even empty, the shed was heavy, but I had a plan.

Across the garden was the substantial stump of one of the conifers we chopped down. I had a large nylon rope that I looped around the stump and trailed back towards the shed. Onto that, I attached a steel wire ratchet winch. I then had three, two inch nylon ratchet straps, hooked together and wrapped around the shed. They were hooked onto the steel cable ratchet.

Then I started cranking the ratchet handle and the shed started to move. It took a while, having to re-rig the winch once the cable was all wound onto the drum, but eventually the shed was dragged to its new location at the front corner of the concrete.

The shed was quite scruffy, the wood dry and covered in algae, particularly on the side facing the garage and hawthorn hedge. I decided not to put the trailer away immediately, but that the shed needed jet-washing and then painting first. We spent the rest of the day putting the contents back in the shed.



With the shed moved, it gave me a good estimation of the view of the sky for the observatory. Since objects reach their highest in the sky to the South, I was pretty pleased with the view.

 

24th & 25th May 2022

The 23rd was spent shopping for planking to box in the plinth and taking stuff to the tip. I got back to the floor on the 24th, cutting more joists to fully support the shed floor.



It took a while to measure, cut, fit and paint each piece, but by the end of the 25th, all the pieces were in place.

 

26th & 27th May 2022

It was raining on the 26th, so since everything outside was wet, I couldn't do anything else. I took the opportunity to jet-wash the shed, as I would get wet anyway doing that. What I expected to be a couple of hours work, turned out to be six and a half hours spraying to get the wood completely clean. The day after was dry, which allowed me to get a couple of coats of paint applied.



Late in the day, once I'd finished with the shed, my trailer was pushed into its new home. The space behind the shed would be home for another trailer belonging to the Girl Guides.

 

28th May 2022

I painted the plinth planks while I was painting the shed. On the 28th, I began attaching them. The area to the left of the observatory would become the base for our raised bed vegetable planters. The ground level would be raised and levelled to just below the timber.



By the end of the day, I'd got the front and most of the right end covered. The inside of the planks was painted in bitumen before attaching.

 

29th May 2022

The next day, I covered the back and shed end. The work was interrupted several times across the day due to passing showers.



30th May 2022

The right end planking was completed after a bit of earth works. In addition to the plinth, I edged the concrete next to the shed to hide the shuttering for the concrete. The builders assembled it with the screws on the concrete side, so once poured, I couldn't get to the screws to dismantle it. Covering it over gave a nice edge and it will be back filled with slates around the vegetable planter. Where the concrete ramp extends down onto the lawn, the edge was also covered in.

It was another day interrupted by rain showers. By mid afternoon, I got several of the floor panels out to mark out the pier locations so the holes could be cut. Everything was packed away fairly quickly as the storm clouds were gathering once again.