Astronomy Log

As you probably know I purchased an Astro Engineering Pro Pier and drilled the holes for the pier bolts at the time I laid the slabs for the base of the shed.

I had thought I was going to secure the bolts at the same time of laying the slabs, but I must admit got a bit scarred about doing it, and then kept putting it off. I then thought about doing it before the shed was erected, but then ended up doing it once the shed was completed inside and out, so in fact I made this the last of my jobs.

I used a bolt kit from Pulsar Optical which was around £35, it includes the four pier bolts, with washers, nuts and dome nuts. It also comes with a tube of gunk which has to be used with a mastik type gun.

I had previously hired an STS drill to drill out the holes, so I began by cleaning out the holes. To do this I attached a small tube to the end of an old vacuum cleaner to get to the bottom of the holes I had drilled.

Next I unscrewed the end of the gunk and found a metal clip around the inner plastic sleeve. I cut this metal clip off and then re-attached the nozzle and place the tube into the dispensing gun.

Now for me, on the first attempt the gunk did not set at all. I was deemed to have been very unlucky as inside the tube there are two colours which must mix together before they are squirted into the pier bolt holes.

For me, this not happen on my first attempt, it looked like one of the chemicals was restricted from leaving the tube. So I thought everything was ok ,so left it overnight and came back in the next day at lunchtime to find the bolts had not set in the groud at all. So off I went back to Pulsar Optical who were straight onto the phone to the manufacturers of the gunk and the MD of the company even phoned them back. The company offered to send a new tube of gunk and some metal cleaning brushes so that I could get the unset gunk out of the pier bolt holes. James at Pulsar Optical also provided me with another set of clean bolts, which was really good of them.

The next day I went back to pick up the cleaning brushes and the new tube of gunk. That evening at about 7.30pm I began again. Once I had cleaned out the holes I cut the metal end of the gunk off and put it in the gun holder. I then made sure this time that I could see the two chemicals mix inside the nozzle. Now it did take at least two full trigger squeezes in order to get a good mix of the chemicals.

I squirted the gunk into the holes one at a time, starting with the nozzle at the base of the holes and filled them to about 50% full. I then took my electric screwdriver and added an attachment so that I could screw the bolts into the gunk in the holes which is now very dense. This allows the gunk to get into the grooves of the bolts.

I repeated this for each of the four bolts in turn. You will find that a lot of gunk will spill over the holes, you just need to have a rag ready to clean this up.

I then lifted the pier over the bolts to make sure the bolts were in the right location. I then left the bolts overnight, and in the morning returned to find the bolts were completely rock solid in the ground.

I then cleaned the bolts up as some had some glue around them which would stop the nuts from been tightened. I just took a stanley knife and chipped away at the glue to clean them. I also removed the pier again, so that I could make sure I cleaned the bolts all the way to the floor as I did not want the glue on the bolts to stop the nuts being tightened as much as possible.

I then placed the pier back on the bolts and tightened them up. Job Done!

There are many different ways of completing this job, as I was advised not to lift the pier on and off the bolts, as the weight of the pier could dent the grooves on the bolts and render them useless, but for me this was not a problem. You could always make a wooden template and use that as a guide. I was worried that the bolts would not set in the correct position, as there is really no room for error, so placing the pier on top of the bolts seemed the most reliable method to me.

Once the roof had been put on and the opening doors re-attached, the work on the observatory was far from over.

To begin with, the next day rain was forecast, and that was the first test of the roof. I sat in the shed whilst the rain lashed down on the roof, and after a while I found I had four leaks.

The leaks came from where we had screwed in the hinges but then moved them, so the next day I was on the roof filling the holes with mastic.

I also found that I needed a lot more felt pins on the roof so hammered a load more in.

I also went to Wilkinsons and purchased a few more ironmonger bits, including some black cast handles which I have attached to the outside of the roof. I also purchased some cheap rope from the pound shop to allow me to open and close the roof.

I ended up buying some screw-in loops to tie the rope to on the inside and then push open the roof from the inside whilst keeping hold of the rope to lower the roof down onto the roof wooden stoppers which I also added to ensure the roof came down horizontally.

I then added the same rope on the outside of the roof and tide it to the black handles on the top of roof, then to close the roof, I go outside with a small lightweight aluminium ladder and push the roof closed, whilst holding onto the rope and lowering the roof back down.

I used cabin hooks and black tower bolts in order to keep the roof down. The cabin hooks attach the roof to the shed, whilst the tower bolts bolt the two roof pieces together.

I also purchased some cheap black carpet from Carpetright and put that down on top of some newspaper. I kept the carpet down by using a standard office staple gun and stapling it into the wood.

I purchased a cheap computer desk from Argos, and added a Belkin UPS so to keep everything on for a while in case the power goes off.

I have also added some shelves, very useful for keeping things neat and tidy, and I managed to purchase a wood drill bit the same size of a 1.25″ eyepiece and drill 6 holes in the shelf in order to hold my eyepieces.

I also purchased some cheap 3m USB 2.0 extension cables from eBay so that I could run these cables under the carpet from the PC to the telescope. This means that I have usb sockets ready to use around the wedge, useful for setting up webcams, DSLR and CCD imagers, plus they were only about £1.60 each.

After painting the inside of the shed all black, all the jobs had been completed except for the setting the bolts in the ground (which is another post) but first I waited a week or so for my dad to come over and help me work on the roof.

We began by taking the roof off again, and first removing the felt. I then found out I had to undo a lot of my previous work and remove some plywood sheets and polystyrene sheets in order to get to the screws that were holding the roof on.

 Next we decided on how large to make the overall hole in the roof. As the roof was tongue and groove wood, it was easier to let the jigsaw cut along where the wood joined itself.

Cutting out the roof was stressful, had I cut out enough? As this is a one time only cut.

We then removed the full piece of roof, but did not cut the roof in half until later on.

 I had purchased two lengths of 4 inch by 3 inch planed wood to go inside the open roof, so creating a lip and so also giving me about an extra 5cm in roof height.

As the main beams of the roof ran in one direction, the 4×3 inch wood could be screwed into that, but on the other direction where there was nothing to attach to,  I had to purchase a length of 2×2 treated wood to create some new beams, this also strengthened the roof some more.

Next came adding the felt back onto the roof in three strips and adding some beading wood to the outside to give the felt a tight fit, we also had to add extra wood to give the hinges something to sit on.

The hinges were from my local ironmonger in Streatham, Cambs. I actually first went for some small ones at 450mm long, costing only £8 for 2 pairs, but as soon as I looked at them overnight I knew they were too small, so I returned them the next day and upgraded them to the 600mm hinges which were a lot more money at £30 for 2 pairs, but they were definitely the correct ones.

We then cut the main roof into half, but not quite in half, because as we had now created an inner roof we did not need to full width of the roof, so took off one section of wood, which left one rof panel slightly longer than the other.

We adjusted the jigsaw blade to cut the roof in half at 45 degrees so I had a slanted section which had to open first (the telescope side of the roof).

At this point we put the roof felt onto the roof panels, and then put on the hinges, but later we found out that the roof felt was being pulled and tearing the felt. So we had to actually cut around the hinge (gate post) end to allow the roof to open up.

We also left an overhang of felt on the section roof which comes down last to keep the rain out of the roof join. I also had to put a large line of felt nails along this line to keep it in place, especially when the roof is open and the felt is upside down defying the laws of gravity.

We then decided to put the roof back on, but not before taking off the roof panels, as now the complete roof was very very with all this extra wood we had added. So we put the roof outer on first, and then re-attached the roof panels afterwards.

To get around the problem of having a gap in the felt where the hinges are, I just put a loose line of felt over the top of the join, this was really going to be a makeshift thing just to keep out the next days forecast rain, but it has worked so well, I have left it in place.

The next day we did have a lot of rain and I stayed in the shed to watch for drips, and I had 4 leaks. They all came about because we moved the hinges once and left open holes. So I went onto the roof with some mastic in a gun and just filled the holes, and I have not had any leaks since.

So now the roof was finished, but there was still lots more things to do, such as securing the two parts of the roof together, which I did with two black tower bolts, and fixing the opening roof panels to the main parts of the roof, which I did with brass cabin hooks.

I also found that the wide part of the hinge attachment had two screw holes that did not line up with the beam underneath, so I could not screw them to anything, so I purchased some small bolts and bolted them through the roof.

So now the roof was on, but I needed to work out how to open the roof. I have ended up purchasing some cheap plastic rope and two black metal handles which I put on each part of the roof section to tie the rope to.

I also purchased a small light 4 step ladder from Wilkinsons for £20 which allows me to open the roof from inside the shed and at the same time hold onto the rope which I also have on the inside of the shed and lower the roof down. Not forgetting that I had also added some roof stoppers on wood to the outside of the shed to hold up the roof panels when open.

To close the outside roof I stand up the ladder and push the roof closed and again lower it down with the outside rope.

There was still lots to do, such as setting the pier bolts and doing some more plywood work and painting as well as moving in.

Once I had installed the Plywood panels, I needed to paint the walls. I was worried to begin with whether I required a grey undercoat or if I could just paint on a black one-coat paint, or should I go for the blackboard paint which is non-reflective.

In the end I purchased two tins of black paint from Wilkinsons which were about £6 each, and they were for wood and metal, (quite handy the paint went on metal as I also painted over the screws in the walls as well).

The paint hardly soaked in at all, and one coat was enough. The paint was very good and quite cheap, plus it was water based so brushes wash out easily as well.

Once I had cut up the polystyrene sheets for insulation and slotted them into the recesses of the shed walls, I had ordered 7 sheets of 8ftx4ft – 6mm plywood to go over the top, these were also to be painted black.

Before I could install the plywood, I had discovered that the shed recesses were 40mm deep, but the polystyrene sheets are 50mm deep, so now the polystyrene is sticking out 10mm, so I could either cut down the polystyrene or pack out the frame by 10mm to bring it up level.

I decided to pack out the frame with pieces of plywood I cut up as well as free wood I managed to get from Travis Perkins.

Now I was ready to cut up the plywood and I panelled out the whole inside of the shed, including the inside of the door.

I also made some shutters for the window using some left over plywood and I then used more plywood to encase the surround of the base, where the pier will be going.

For my 8x6ft Pent Shed I could have done with 8 plywood sheets, but I did manage to complete the job with 7 sheets, but had to have one side of the shed wall made up of several cut pieces instead of using just one board.

Next comes painting the inside of the shed.

Once the pent shed was erected, I then considered the insulation and the types of products I could use.

I went for 50mm polystyrene sheets which measured 8ft x 4ft, again I ordered these from Buildbase as they were a lot cheaper than Travis Perkins, at around £7.50 each inc VAT.

I also ordered some sheets of 6mm Plywood at the same time, as I wanted to cut the polystyrene sheets into the recesses of the shed and then have the plywood over the top. The plywood was the most expensive item at around £14 for a 8ft x 4ft board.

I ended up ordering 7 sheets of both, with the polystyrene cut and fitted, I had one board left over, so I actually only needed 6 sheets for the 8x6ft pent shed.

Cutting the polystyrene sheets was quite messy, and the garden now resembled in parts a snowy type of winter wonderland scene, with all the residue of the polystyrene balls everywhere. I actually cut the sheets with a saw, and it was really easy to do.

The only problem has been that the shed recesses are 40mm deep and the polystyrene sheets only come in 25mm and 5omm depth, so I now have the polystyrene sheets sticking out by 10mm.

To get round this I could have either thinned down the sheets, but a very messy job. I did think of cutting up polystyrene strips in 10mm depths, but again probably a difficult and messy job.  So I ended up cutting strips of plywood for one inner wall. I actually used 2 pieces back to back to layer up to the correct height.

On the other three inner walls I used some rough wood which came from Travis Perkins pallets, the wood actually spaces the main wood on the pallets. It was the correct width and depth, and they nicely let me take as much as this as I wanted.

So far I have insulated the whole of the shed including the door, but excluding the ceiling, I may insulate a part of this when I work out how I am going to have my roof open up, I may also insulate the main part of the ceiling with a thinner lighter silver reflective sheet, but we’ll see.

Saturday I finished off the slab laying and painted the shed some more, to give it two coats all over. Sunday my father came to help me in the afternoon erect the pent shed, as this is definitely a two man/person job.

We began by marking out where to cut the hole in the base of the shed to leave the space for the pier. We then re-inforced the underside of the shed base with extra wood battens which I purchases separately. We did this because once we had cut a hatch in the floor, the floor lost a bit of it’s strength especially when walking near the edges of the hole.

This part actually took the longest time, as then we put the back of the shed on first, together with a side, and then the other side, and the front, all of wich went up quite quickly.

I was amazed at the actual height of the shed, I had ordered it to be 1 foot taller at the back and front, and I was worried that the Telescope won’t even see Polaris or anything else for that matter. Anyway next came sliding the roof on and then we put the felt on the roof, but perhaps next time I may put the felt on the roof before we put it on.

Then it was time to finish for day, I had left it water tight, whilst I decided and designed how I want my roof to open. Although there are still lots of jobs to do, including fixing the corner external vertical battens, putting in the windows, filling any holes, putting on the electric, touching up any bits I missed with the stain, and also get the shed lined and getting plywood put up, it’s not over yet!

Saturday morning I carried on mixing cement and laying the slabs. At about 11am I had a break and went off to my local tool hire shop where I hired the SDS Drill and 110V to 240V converter to make the holes in the concrete for the pier bolts, which cost about £19 for the weekend.

I also called into ScopesNSkies where James lent me an 18mm drill bit for the pier holes. I had previously been into ScopesNSkies during the week to purchase the Pier Fitting Kit, which consists of 4 bolts, washers and nuts, you get the tube of resin included, but you will have to remember to get a metal gun for the tube of resin.

Once I got back home, I drilled the 4 holes in the concrete. I was very worried about not making the holes in the correct place or drilling them at an angle. So I drilled one at a time then moved the pier into place and re-checked the other holes and re-marked them again.  A lot of concrete powder came out of the ground when drilling the holes, and I was advised to use my hoover to suck out the dirt left in the drill holes, as they need to be as clean as possible when putting in the bolts and resin. So I began looking for a piece of hosepipe to tape to the hoover attachment, but the hose pipe was too large to fit the drill holes, so instead I used a plastic tube which comes with those expanding foam cans.

I now needed to set the bolts in the holes with the resin in the kit, but I did not do this straightaway, I actually left it until the whole shed was put up.

It was now the weekend again, and the concrete has been left about a week to set. It was now time to lay the slabs for the base of the shed. All week during the evenings I have also been staining the shed. In the end I managed two coats on all sides of the shed, but boy I wish I had ordered the shed pre-treated, it may have cost a little more, but it would have saved me a lot of time.

I began the weekend by making a couple of small purchases late on the Friday night, firstly I purchased some Bitumen weatherproof gunk, to paint onto the concrete pier base, as I was worried about water sitting around the base of the pier. I also purchased a small tube of Ronseal Wood Filler to fill any holes in the shed where the knots had fallen out.

I had ordered 8 bags of sand (4 Sharp and 4 Soft) as well as 2 bags of cement for the 11 slabs I was laying.  I was worried I would not have enough sand, and all the builders merchants close at noon on Saturday near me, so may last chance to get more was around 11.45am (even though in the end I had 2 bags spare, so only used 6 bags). So because of this Friday night I laid 3 slabs just to work out how much sand and cement that had used, but it seemed I had ordered about enough. 

I finished off laying the slabs on Saturday (the next day). I actually purchased the cheapest slabs I could find which are Council slabs in grey, these come in two depths, but I went for the thinner ones as these are already heavy enough anyway, and the 600mm slabs are quite awkward to work with compared with the smaller 450mm slabs. I paid about £3.50 for the 600mm Council slabs from Buildbase. I ended up hand mixing the cement I needed to fix the slabs down in a wheelbarrow as then I could mix about the right amount everytime for one or two slabs.

Things are still pressing ahead around normal paid work and looking after my son. But today I had the shed delivered and the slabs, sand and cement from Buildbase. Whilst unloading the van I remembered just how heavy the 600mm concrete slabs really are and how they will break my back when I come to lay them out. I usually use the smaller 450mm which are a lot easier to handle, but their size this time just did not fit the plan.

I ordered the shed untreated, so visited Wilkinsons to buy some stain the other day, I nearly purchased the Cuprinol brand, but at £15 for 5litres, I went for the Wilkinsons own brand which looked just as good for £6.99 for 5litres. In the end it’s probably the same stuff and probably made by cuprinol for Wilkinsons anyway.

I painted a few sides of the shed tonight before it got too dark to see, but I think I will need a couple more 5litre tins of “English Oak” before I am finished, especially if I am staining inside and out and giving the bottom of the floor several coats.

I think next time I will get the shed supplier to treat the shed for me before delivery, saving me a bit of time, as they charge 10% of the cost of the shed to treat the shed, which would have been around £35-£45, a little more costly than doing it yourself, but probably worth it.