JamesF's observatory build

[JamesF]

I had to get some wood from the builders' merchant today to make up new doors for the polytunnel, but 4.8m lengths of 50mm square timber don't really fold up sufficiently well to fit in the Fiesta, so I ordered all the ply for lining the walls etc. at the same time, making a big enough order that they'll deliver it (some time next week now, I imagine).  Meantime I still have the door to make and the "leak" to resolve.

As I had to go past Screwfix this evening on my way to collect my son from an after-school thing, I stopped by and picked up some stainless screws for fixing the ply.  I could probably get away with normal ones as they'll be painted over, but if they did get damp and start to rust it would irritate me, so this way I just avoid any such problem.

Would be nice to make some progress on the door this weekend, but we'll have to see how things go.  The improvement in the weather means lots of other jobs are wanting attention, too

James

[JamesF]

Yesterday was spent outside in the sun dealing with other domestic chores, but the sudden drop in temperature today meant no-one else wanted to be outdoors for any longer than they absolutely had to be, so I gathered up some 4x2 with a couple of offcuts of 6x2 and 8x2 to make up a frame for the external observatory door (a frame for the door, rather than a door frame .  I used the 4x2 to make the stiles and top rail, the 8x2 for the middle rail and the 6x2 for the bottom rail.  Much as I'd have loved to join them all using dowelled mortise and tenon joints, it would have taken an age, so I just went for glued and screwed lap joints in the end.  That still took more than long enough.

Once the frame was made I decided I'd fit the hinges and hang it before I fitted any of the cladding, the door being much easier to support when I could put my arm all the way through it.  I needed a small amount of work with the electric plane to get it to fit, and that's as far as I got.  I still have to fix on some membrane, add the cladding, line the inside, fit a lock and put the door stop on the inside of the frame.  I'm sure I have several locks lying about somewhere if I can just remember what I did with them.

Tomorrow I'll try to get some membrane fixed on the front.  At least then it should mean that there's no possibility of rain getting into the scope room through the opening, and after quite a long period of dry weather it appears that rain is once again forecast for midweek.

No photos yet.  I worked right down to the wire and didn't have time before it was dark.

[JamesF]

I was just about to go out a few minutes ago and take a photo of the door when I heard the bleeping of a reversing lorry.  The ply for the internal wall lining has arrived a day early.  Now I just need to get it under cover.  And make some decisions about lighting, so I can make sure I have everything I need in place.

James

[Dr_Ju_ju]

no rest for the wicked.....

[Astrokev]

Making good progress. Look forward to the pics when you can squeeze them in!

[JamesF]

Here you go, then.  One observatory door after I fixed on some membrane this evening:

Needs some sort of handle on the outside for the moment, otherwise it's a bit awkward to get in

I was planning on fixing some diagonal bracing into the frame, but as it's going to be covered with a sheet of ply on the inside which will effectively do the same thing I decided not to bother.  The centre rail makes it pretty rigid anyhow as it happens.  I've still left the other old door over the opening because it's certainly not weathertight yet, and I don't need it blowing open in the wind and letting rain in or something like that.

Most of the rest of the remaining daylight was spent moving the ply delivered earlier today inside as the weather is supposed to be fairly miserable for the rest of this week, but I couldn't resist screwing one sheet to the wall (whilst remembering to mark the positions of the timbers behind it   There aren't many places where a sheet will go in uncut, but I'll try to do those first just to get through the bulk of material as quickly as possible.  I do also want to get one side of the warm room wall done early on so I can fit the remaining insulation and check off another job.

After discussions with Alex in his build thread I've decided to go for the same lighting setup as he is using, with a strip of LEDs in recessed aluminium channel in the walls.  I reckon I'll use most of a 10m strip going around the walls from the far side of the warm room window, along the eastern and southern walls and back along the western wall to near the edge of  the door.  Having light from so many different directions should address my concerns about shadows I think, and if it isn't bright enough I'll add some more in the roof at a later date.  Knowing that's going to be what I do means I can fix the sheets of ply in on their sides all the way around and put the aluminium channel for the lighting strip on top of that and finally put the section of ply in to cover the top section of the wall.

So, lots to do once again

James

[JamesF]

Ah, yes, note to self:

Remember when fitting the cladding to the outside of the door that there will be much gnashing and wailing of teeth if you put nails through the part of the frame that needs mortising to fit the lock.  Or even if you try to nail through the lock having put it in first.

Perhaps a truly wise man would mark this area on the door frame before starting to clad it.

James

[Stub Mandrel]

If all else fails...

[Rusted]

I use a padlock and hasp with concealed coach bolts too.
Large metal plates hidden out of sight inside the door spread the bolt loads over a huge area.
It should really spoil the day of any crowbar swinging low life who fancies a free fix.

Never leave exposed heads on hinges or hasps or any other vulnerabilities!

The cheapest hasps can be levered off with an electrical screwdriver!

The best hasps actually hide the padlock inside a little box to protect against bolt cutters.

I needed bolt cutters to trim my sturdy veranda fencing and found them as cheap as 20 quid.
Though I went for better quality in a slightly larger size to make [my] life much easier.

 

[JamesF]

This evening the observatory has started to take on the appearance, if not the temperature, of a sauna   It is in fact quite chilly out there are the moment -- not a whole lot above freezing, and we're forecast to get sleet from the small hours tomorrow.

Working with sheets of ply that are a third of the floor area of the scope room and storing all the others in the same space makes it a bit tricky to move about, but it does make work possible when it's tipping down and this evening I have completed the lower section of the western wall of the scope room and I just have one section left for the eastern wall.  That should be fairly easy to sort tomorrow, and if I can get the internal door liner in as well then I should be able to fit the lower section of ply on the scope room side of the internal wall which means I'll be up to "lights level" in the scope room, just in time for them to arrive towards the end of this week.

James

[Dr_Ju_ju]

Sounds like you're motoring along.....

[Gina]

We had lots of heavy hail showers here today.

[JamesF]

Same here, Gina.  Mainly this afternoon, I think, but it was still pretty unpleasant outside even when I was working in the observatory.  I could hear something hammering on the roof whilst I was inside.  I wasn't keen to open the door and look however :)  By the time it had finished and I decided it was safe to leave it was too dark to see much at all.

James

[JamesF]

All the parts for the scope room lighting appear to have arrived :)

The basic kit with the LED strip itself includes the PSU and an IR receiver that controls the LEDs with an IR handset.  The wifi controller also comes with a handset, which I didn't expect given that it's supposed to be controlled using wifi.  The IR receiver responds to both handsets, but not in the same way (so, the on/off button works as expected on one, but doesn't work on the other, where the "orange" button actually does on/off).  That took me a few moments to work out :)

James

[Astrokev]

Great progress James. The end’s in sight!

What LED strip did you go for in the end?

[JamesF]

3 minutes ago, Astrokev said:

Great progress James. The end’s in sight!

What LED strip did you go for in the end?

I used the same ones that Alex linked to in his thread:

https://www.amazon.co.uk/gp/product/B01N454RVY

https://www.amazon.co.uk/gp/product/B07P8YFPS3

https://www.amazon.co.uk/gp/product/B079K7QZPN

James

[Astrokev]

Great, thanks James.....and Alex!

Not sure I need the luxury of wireless control (or maybe I do but just don’t realise it ?); at present I’m thinking of going for a simple on/off wall switch. 

Will also check out surface mounted conduits. Those flush fitting ones look great. Wish I’d thought of that before fitting the wall panels ?

Edited April 3, 2019 by Astrokev

[JamesF]

With the dimmable LED strips it appears to me that a "simple" switch isn't feasible, though there are wall-mounted controllers, also with a link in Alex's thread.  Or perhaps the non-wifi IR-only solution would be sufficient for you?

I think, though I've not definitively confirmed this, that the LED brightness is controlled using some sort of PWM circuit, effectively turning the LEDs on and off faster than we can see.  The longer the LED is on compared with off, the brighter it appears.  A standard lighting switch (which was what I originally had in my head to use) won't do that, though it's probably achievable if the switch is combined with, say, an Arduino.  At this point however it starts to get sufficiently complicated that I decided I'd rather have something that I didn't have to faff about with to get working.  At least for the moment.  Given the wifi option there may well come a time when I write a driver for it so the lighting can be controlled from a PC along with all the other astro kit :)

You can get single-colour dimmable LED strips, so in theory could perhaps connect those to a PWM dimmer which is in turn fed from a "standard" light switch (even if it's only switching 12V).  Leave the dimmer set to your preferred setting and you may well be sorted.  Obviously you'd then need two strips of lights though, one red and one white.

James

[Astrokev]

Thanks James. One of the reasons for me wanting to keep it simple is that I don’t really understand electrics, as I think I’ve said in other threads. You’ve given some good options above so thanks ?

Edited April 3, 2019 by Astrokev

[JamesF]

Teensy bit more progress with the ply this evening, but I'm having to make cuts now so it's taking longer.  I did also start on the internal door lining, but that needs a few trips back and forth to the workshop.  When I was about half done the heavens absolutely opened and I really didn't fancy getting soaked, especially given how cold it's been so far this week.  It will have to wait for another day.  No complaints, regardless.  It's all progress.

James

[JamesF]

More ply fixed into place this evening.  The scope room is now all done to lighting height, the internal door lining is (mostly) in, and the side walls and half the end wall of the warm room are done.

I realised this evening that there is a bijou problemette finishing the walls once I have set up the gap for the lighting channel though: my roof is currently held in place using sash clamps fitted over the roof frame at the wheel positions and under the top rail of the walls.  That won't be possible once the rest of the lining is in place.  I'm going to have to get that done sooner than I thought.

James

[Yawning Angel]

Not having experience in building on this scale, I’ve found getting things done in the right order to be one of the biggest challenges. At least you aren’t undoing work due a planning ‘hiccup’ ??

[JamesF]

7 minutes ago, Yawning Angel said:

Not having experience in building on this scale, I’ve found getting things done in the right order to be one of the biggest challenges. At least you aren’t undoing work due a planning ‘hiccup’ ??

I absolutely agree.  On a number of occasions I've thought "This would have been a lot easier if I'd done it before that", partly because it's hard to think of every little thing you might need to worry about, and partly because of outside factors.  For instance, I'm still waiting for a reliable couple of days of sufficiently warm weather so I can glue down the EPDM, at which point there's a load of other things I need or have to do that I'd prefer to have got sorted already.

It's fine though.  It's not as though I have to get it all done by any particular date and I'll just keep pushing on as and when I have time.  The extra daylight in the evenings is really helping now.  It would be quite nice to have one pier usable, even if the electrics aren't in and the warm room isn't complete, by the first anniversary of me starting though.  So I've got eight weeks

James

[MCinAZ]

18 hours ago, Yawning Angel said:

Not having experience in building on this scale, I’ve found getting things done in the right order to be one of the biggest challenges. At least you aren’t undoing work due a planning ‘hiccup’ ??

  I've found that completing the design to the last imaginable detail in advance, along with giving consideration to the process required to complete construction, helps immensely. Of course, the second part of that is largely experienced-based -- you don't really think too much about how you're going to swing a hammer in some confined space unless you've previously created the need to do so.

  Perhaps the biggest error I've made (and consistently see others making) when it comes to a building with a movable roof is failure to fully consider the logistics associated with achieving adequate weatherproofing while still allowing for movement. It's not a trivial problem, but getting to the 90% completion point during construction then trying to find a solution is asking for trouble. The second and third roll-off builds I managed were much more successful only because, unlike the first build, I used a CAD program to determine where every piece of lumber and trim would go before the first shovel full of dirt was moved. It's so much easier to move a 2x4 or add 1/2" to the width of the roof trusses on a computer screen than at a building site.

[JamesF]

I took the day off today.  Unfortunately I ended up having to spend most of it fighting with the leaky overflow on the bath.  I couldn't tighten it and I couldn't unscrew it to reassemble everything properly, so I ended up taking a hacksaw to it and fitting a completely new one which ate into the day rather more than I'd planned.  Perhaps it was no great loss as the weather today has been pretty grim.  After I swam this afternoon however, I sneaked off to the observatory and fitted the last section of ply to the northern wall, loosely fitted the window in the internal wall so I can do the lining around it and cut and fitted all the insulation for the internal wall below "lighting height".  By the time I'd roughly cut the ply to finish off the lower half of that wall I decided it was just getting too cold and called it an evening.

Before I go any further I think I'm going to have to have a bit of a clean up.  There's sawdust and wood shavings everywhere now from all the cutting I've been doing inside.

James