Dressing off and improvements

This page is just for all the other little things I have done to constantly improve the observatory.

Concrete paving and garden border.

Concreting takes time and effort. You must take the time to prepare the ground and formwork first. Formwork is any supporting material that will hold the form of the concrete while it is wet and soggy, until it sets. Once set, formwork is then pulled out.

First, measure, mark and dig all the holes necessary. Dig them all a little bit deeper and wider than you need. You can always put some loose dirt back in the hole later. Make sure all the formwork is pegged or supported in such way that it will not fall over when the concrete is poured. Compact any loose soil in the bottom of the holes or areas to be concreted. If you don't, you may increase the chance of the concrete cracking later, when the soil underneath settles. If you think the volume of concrete warrants, place reinforcing material in the cavity to be filled.

Make sure you have all the tools on hand for mixing and working the concrete before you start. Also make sure you have enough sand, cement and aggregate needed to complete the task. It is always better to have some left over than to run out halfway through the job. Aggregate is the gravel or stone that is mixed in with cement, sand and water to give more bulk and strength to the mix. The size of the aggregate is measured according to the type of concreting you wish to do. I used 20mm aggregate for my mix. If you were doing any surfacing or thin work, you would use smaller stones or no stones at all.

If you don't have a cement mixer then you can mix manually in a wheelbarrow or on a large piece of plywood. My mix ratio was about 4:1:1. That is four shovels of sand, one shovel of cement and one of aggregate. Mix them all dry then add water gradually. You only want the mix to be just wet enough to work. Too much water causes the chemicals in the cement to segregate, causing weak concrete. You can use just a little bit more water for finishing off surfaces if needed.

Once mixed, pour or shovel the mix into the cavity or area to be filled. Use a tool called a float, which looks like a small flat plank with a handle on top. You can use a block of 4x2 timber off-cut, small enough to hold in one hand. (I did). Use the float to smooth the surface in a gliding and dragging motion, Don't worry, you will catch on. Practice will teach you all you need to know. If you have a large flat area to get even, use a long piece of timber. Lean over the work, pull the timber towards you while shaking it from side to side. You can bring the mix to a smoother finish by using a patting motion with the float on top of the cement. This is called, "Bringing the mud to the top.".  You can then use your float in a gliding motion to smooth it all off.

For a professional touch, paving can be given patterns either by stencil or manual means. I waited for the cement to firm a little, then used a stiff broom to give a lined texture. I then dressed off the edges by dragging the float around as a border for the textured centre.

If you have large flat areas, remember to break it up with a pressed-in join. I used the edge of some 6mm plywood. That way if the ground shifts and it cracks, it will crack where you want it to instead of an ugly, crooked crack. Look at a standard concrete footpath for example. You will notice footpaths are rarely one long, continuous, length of concrete.

Lighting.

I painted the Perspex in front of the fluro lights red, then cut and painted a neat frame to dress it off a little better. I have also made a small Perspex, hinged flap to fold up over the stair halogen light and will be secured via double sided Velcro tape.

Interior enhancements.

The dome has been painted with two coats of low sheen ceiling paint (white) and I have installed four poster boards and one photo/article board. Later, I will make some wooden pockets to fit some books and magazines in either on the walls of the observatory or inside the dome walls.

Heat is beginning to become a bit of an issue, so to tackle this, I am going to try gluing some insulation to the inside of the plywood. It looks like I may have to dress that off with something too, as it is quite ugly. The difference in temperature is apparent already!

I found some felt padding material leftovers that my workplace was kind enough to let me have. Although there wasn't enough to do the whole interior in one colour, I think the three tone patterned effect looks very nice.

Dew shield.

I purchased 2 pieces or black ripple cardboard to form a tube that will fit over the end of the telescope. I'm not sure if I will even need a dew shield with the 'scope inside the dome, but hey....it looks good! I used wood glue and black 100-mile-an-hour tape to secure it all, keeping it as neat as possible. I then printed off a couple of logo's to make it look authentic and gave it a couple of coats of lacquer to seal it.

Pier Box.

I constructed a box to tidy up around the pier and to stop people from tripping or kicking the cords. The middle has a hole cut so that it does not contact the pier in any way.

Dress rehearsal.

Time to mount the scope, check that everything goes where it should and look for more ideas to improve the whole thing.

Seating

I'm getting tired of standing up all night and if I ever have a few guests, it would be nice for them to have somewhere to sit out of the way, while they each take turns at the eyepiece.

I built very nice seats and shelving out of scrap material from an industrial bin! All finished off with a coat of paint and maybe some artwork or something later. Each seat is contoured to the walls and extends out only 400mm. This leaves plenty of room to walk around the telescope. On the underside of the seats, there is room to build shelving and sliding doors to keep everything tidy if needed.

Finished

Finally, here's the finished interior of the dome, with everything ready and operational.

Swivelling Computer Table.

There seemed to be a need for a place to operate imaging software in a convenient location around the pier. If a fixed platform is attached, then it can get in the way of telescope/user operations. This called for a table that could swivel out of the way.

The table is made from a piece of craftwood cut to size. Underneath is a frame of square steel tube, welded in the corners for rigidity. In one corner, a hole has been drilled in the tube to fit a length of mild steel round bar approximately 12mm in diameter. (1/2 inch)

The bracket is mad of a piece of mild steel flat bar with the ends drilled to a little over 12mm, then bent over at the ends. This is screwed into plastic wall plugs, pushed into holes drilled into the concrete.

The round bar on the table then just slips down through both holes of the bracket. The table is then finished off with some padding and a vinyl covering stretched over and secured underneath with staples or tacks.

Hand control bracket.

To place the hand controller in a convenient position, a bracket is needed that will allow easy-in and easy-out, when needed.

Basically, measure and cut two strips of 20 x 3mm aluminium flat bar and rivet together in a crucifix configuration. Shape the top end with a file to fit into the slot at the back of the controller. (Celestron). For other controllers with no slot at the back, just have a look at mobile phone in-car cradles for ideas.

The cross bar is then bent to fit around and cradle the bottom of the controller in a snug fit. File and sand all edges to avoid scratching the controller.

Trial fit the bracket with controller in different positions around the pier to find the best location, then screw it on to the pier. Pretty it up later with some emery paper and a slap of paint.