Astrokev

On ‎01‎/‎01‎/‎2019 at 23:02, JamesF said:

That's certainly going to make it far more awkward to get water to flow along that channel any further.  Hopefully it will do the trick.  I may need to consider the same problem with my own build, although in my case the gap is much narrower.

James

Yes I hope so. In my case I think the problem was exacerbated by the rain running off the rolling roof directly into the channel. A back of the envelope calc suggests this was more than doubling the amount of water in the channel, with most of it being dumped exactly where I don't need it - ie, right next to the transition from the outside into the scope room. The guttering has sorted that one out. The only water that will now be in the channel is that which directly falls into it from the heavens, and it will be evenly distributed all the way along the channel. On the assumption that the channel is fairly level (or at least doesn't have an end to end slope of more than ~10mm), then any pooled water should run out of the north end of the channel before it overflows my mini-dam. 

Well, that's the theory! If I'm feeling brave, I may test it with a hosepipe or watering can. 

Should've made better use of the decent weather today, but for some reason just couldn't get into gear.

Rather than fit the guttering I bought yesterday, I thought I ought to try and work on making a small water barrier on the rail beam while it was dry, to try and stop water running along the beam under the ROR and into the scope room.

Here's a rubbish close-up of what I came up with. Having considered a few different approaches, I ended up using contact adhesive to stick a stack of EPDM layers onto the beam between the rail and the warm room roof, to form a barrier about 10mm high. I couldn't make it any higher otherwise it would foul the wheel. I then glued another piece on the outer face of the stack. This looks a bit messy in the picture, but it's formed a solid block of rubber which I think should be effective. Although the adhesive has formed a good seal, I'll also add exterior silicone sealant to make sure this is fully water tight once I've made a similar barrier on the other rail. The barrier sits just behind the cladding, which is removed in the pic to give me access, and won't be visible once the cladding is reinstated. Even without the cladding it was really fiddly to get under the beam which holds the roof wheels. I really wish I'd considered this before I built the ROR when it would have been easy to make and fit a much better arrangement! Anyway, one side nearly done and I'm pretty confident this will do the trick, in addition to the guttering above the rail.

I'm also considering adding a short section of brush on the outside of the cladding to sweep the rail and rail beam every time the ROR is opened. With the pine trees in next door's garden I get loads of needles on the roof, and this will help keep the track clear, as well as reduce wind blowing needles under the ROR.

3 hours ago, JamesF said:

 cutting the worktop for the boot room cupboards has left me with an off-cut that will be just the right size for a desk in the warm room

 

what a convenient coincidence ?

No work on the observatory today, but did buy a load more plastic ware for the south side of the ROR. Blimey, can't believe how how much it costs when you add up all the little bits ?.

All being well, I'll be back out there tomorrow ?.

Nice simple jobs today. I put up the short gutters on the ROR north edge. It's a bit tricky taking pictures of black gutters in semi shade against a dark background, but hopefully you can see the basic principle. I must try and get some better ones. Although not essential, I still need to neaten up the edge of the EPDM between the gutters.

I also slapped a coat of paint on the upper edge of the scope room walls. These had been left bare until today and, although they won't get wet from rain, I realised they will get wet from dew, so thought it best to give them some surface protection in addition to the coat of preserver.

Next job is to try and construct small water barriers on the rail beam to help stop rain pooling and flowing into the scope room. Although the gutters should reduce the amount of water falling onto this surface, I think it's still likely to be prone to pooling in heavy rain.

Where does the time go?

Bought the guttering I need for the north side of the ROR, and a few other bits. The guttering will catch water flowing off the ROR and redirect it onto the centre of the warm room roof.

By the time I was home and had lunch it was already dull outside. Anyways, I made up some brackets to attach the guttering and gave them a coat of paint, but that's all I could do before it was too dark. No pictures taken but will share some once the guttering is up. 

First post in a few days. Quite nice weather today so decided to drag myself out of my Christmas laziness to do a bit of work on the obsy.

First job was to attach the door stops to the frame. Finishes the door off quite nicely and will hopefully keep out wind and, more importantly, stop rain from seeping behind the door. The door closes with a nice solid clunk now, which is quite satisfying. Just got to paint the internal face when I "decorate" the inside of the warm room.

I then thought I'd brave it and stick down the EPDM to the east and west edges of the ROR. There was some method in my madness. I realised that I really needed to get the EPDM finished off to allow me to put up the guttering on the north corners of the ROR which will help me fix the rain-ingress problem. It was really a bit cold for this; the contact adhesive was like spreading treacle, but the finished job isn't too bad (I still need to trim off the excess EPDM), and these edges will be covered by barge boards once I've made them.

In whatever daylight was left, I checked out the north-west corner of the ROR, which is where the rain was getting in. Most of the time was spent just staring at the design, mentally trying out different ideas and possible solutions to keeping the rain out. I think I've decided what to do, so will crack-on with this tomorrow once I've bought some guttering.

Sensible approach there. I did something similar by trying to put most of the joins on the face that was most protected.

Just taken up the corner of the floor where it was wet. It's pretty much dried out since yesterday which is a good thing, but I'll leave it up now until I've finished fitting rain protection measures. My bucket had collected a fair bit of water, so it was good to have stopped this going into the ply ?.

Pleased that my design has removable floor panels, rather than them being fitted under the walls ?.

I've found another old image which shows the suspect area quite well. This is a view of the rail and rail support beam at the corner of the warm room where the drips are coming from. It clearly shows lots of pine-needle debris - either blown in, or brought in by the rain which may flow along the gully between rail and warm room roof. The flap of EPDM is where the water was dripping into the scope room (green arrow). I probably haven't noticed this before now, since this is the first significant rainfall we've had since the floor was put down. In an earlier post I mentioned one of my jobs was to tidy-up the internal EPDM - well, this is the bit I was referring to, as it's a bit of a mess at the moment! It was left as-was when I finished laying the EPDM on the warm room, with the intention of returning to tidy and neaten the EPDM so it doesn't hang into the obsy. One of the jobs I still haven't gotten round to.

It should be possible to construct a low retaining barrier out of EPDM and silicone between the edge of the roof and the rail, to go roughly where the red arrow is pointing. The problem is this can only be about 10mm high, otherwise it will fowl the wheel as it rolls along the rail. I'll have a closer look when it's dry and see what I can do. If this is possible, I'll probably put 2-3 barriers separated by a few inches to form a series, in case the outer one is breached.

Another thing that I think is contributing to the severity of the problem is that, at present, water runs off the scope room roof directly into the gully between the warm room roof and the rail. Another job on the list is to fit small sections of guttering at the edges of the scope room roof, to redirect the rain onto the warm-room roof instead of into the gully. I remember @Ginaused this approach and it's always been on my list, I just haven't got round to it yet. This should reduce the amount of water in the gully considerably.

15 minutes ago, yesyes said:

I did but never implemented it. I was worried bout the same thing but for some reason (not sure why) I don't get water in this way. (though it does blow in some fine snow when the weather is just "right").

I'm guessing my runners aren't perfectly straight and water runs off towards the outside.

I do have 2 of these huge paint brushes lying around that you would normally use to apply adhesive to wallpaper. Those fit into the opening perfectly. I'll use them if it ever becomes a problem.

thanks Chris

11 minutes ago, Yawning Angel said:

It might also run under the V, if it has access. 

D'you mean the rail?

2 hours ago, Dr_Ju_ju said:

Ouch! the uprights will be ok, but hoping that the flooring doesn't de-laminate, it shouldn't, but I've had some 'supposed' good quality go on me...

?

1 hour ago, Yawning Angel said:

In this constant drizzle, I’m seeing water tracking under the rail from the exposed side into the scope side. I’m thinking of solutions at the moment. I’m wondering if a notch under the rail at the transition might interrupt its route

Need a dry spell to investigate properly, but it’s only dripping slowly, and I’ve no floor yet. 

I think @yesyesconsidered this approach if I recall.

I certainly recognised the risk of water getting in at this part of the building when I was planning, but decided to leave thinking of the best prevention until the main building was finished. Maybe I should've thought about this earlier.

Brushes may help wind blown water, but I doubt they will stop water tracking along the beam that supports the rail, so I need to think about that one.

My EPDM goes under the rails and then overhangs the edge of the warm room roof, so that's pretty well protected. As you've found, the main problem is where the rails enter the scope room from the exposed side. I made sure the roof had a good overhang over the corners where the rails enter the scope area, so I don't think direct rain is the problem. I'm pretty sure it's water tracking along the rail beam, which acts as a gully between the edge of the warm room roof and the rail. The pic shows the affected side before the rail and roof were put on. The rail runs down the centre of the beam, creating a gully of about 10-15mm. In heavy rain, I guess there's nowhere for the water to go but into the scope room  

I've put a bucket under the corner beneath the rail and can hear dripping, so this would seem to confirm the main cause. A nice job for the new year I think. A hefty line of sealant to form a "dam" across the gully may work, or at least reduce the risk.

Bit of a shock this afternoon when I opened the observatory to store some holly - I was greeted by a large damp patch on the floor opposite the door ?.  The patch spans both warm room and scope room, with some of the beams of the wall dividing the two rooms also being damp, as is a patch of the outer wall membrane next to the dividing wall.

I've had an initial look-see to try and figure out where the water's coming in. Three main possibilities occur to me -

1) The roof rubber membrane is leaking. This seems unlikely as the roof OSB feels fairly dry.

2) Rain is blowing under the edge of the roof above the warm-room. The rubber sheet over the beam at the top of the dividing wall is quite damp, so it's possible that water blowing under the roof is dripping down the internal face of the beam. But even if this is a problem, it's difficult to believe this would let in enough water to create the quite sizeable damp patch. The edge of the roof isn't finished yet - the gaps between the rafters are still open where they rest on the cross-beam. I intend to cover these with ply which will stop wind blowing between the rafters. I also plan to put some kind of seal between the roof cross-beam and the beam at the top of the warm-room roof. This will hopefully stop rain blowing under the roof and over the top of the wall beam.

3) Rain is channelling along the beam that supports the roof rail and is dripping inside the scope room. This seems the most likely, or at least the main source of the problem, as I noticed a large drip hanging off the edge of a piece of untrimmed EPDM at the end of the dividing beam. The flat face of the beam supporting the rail was also very wet.

So, for the moment I've decided  to leave it as is. I'm pretty busy this afternoon so don't have time to fix the root cause, but I'll certainly be pondering on the best way of blocking the channel over a mince pie or two later. I recall other folks who had similar problems with their build, so would be interested in suggestions. Making some sort of shallow barrier, like a mini-dam, feels the most obvious fix.

Pleased to hear that you managed to get something done. Sounds like good progress ?

Every bit of progress is good progress, no matter how small....

Attached the door hook and eye catch this afternoon. Now I can hopefully stop worrying about leaving the door open and risking damage by a gust of wind.

I've also painted the internal door stops. Weather permitting I'll try and get these up tomorrow.

1 minute ago, JamesF said:

I think I'd have to cancel Christmas in favour of getting the observatory finished

James

Don't tempt me

The sun was shining today, so I found a bit of time to spend in the observatory.

Finally attached the baton on the door to cover the gap down the lock side and gave it a couple of coats of paint (the pic was taken before doing the second coat). Although this is mainly to keep rain out of the gap, I used stainless security screws as an extra deterrent. The door is essentially complete now, apart from painting the interior at some point.

I also took up the floor in the scope room and put a coat of exterior varnish on the underside. Probably overkill, but this may help reduce the risk of damp air rising from the ground under the building and affecting the plywood. This was touch dry by mid afternoon so screwed the whole floor finally in place. All floors are now finished. Next jobs are to paint the pier, fill the gap between the ply and the pier, then put down rubber floor tiles. I still need to fix some locks (probably turnbuckles) to the roof; maybe this should go to the top of the priority list, so I can sleep easy). With Christmas looming, and loads still to do to prepare for the big day, not sure when I'll next get out to the observatory - hopefully not too long. 

It's strange that something as innocuous as water can be so horrid sometimes!

Not much progress the last few days due to Christmas prep and weather, but I did manage to paint the door baton, which is looking very festive on my dining table!

Just need a decent day to attach it to the door now. 

I was in the observatory last night trying to image comet Wirtanen, and was reminded that I still need to put up some guttering. The rain was dripping off the roof onto my DSLR lenses. ?

23 minutes ago, Bizibilder said:

An excellent job!!  Gina beat me to say put a bit of foam in that gap (Don't ask why I know that is a wise decision  !!).  

Haha ?  

Thanks, but the build isn't there yet - lots still to do ?

1 hour ago, Gina said:

Excellent, Kev!   Well done!  ?  I think some foam strip around the pier at floor level would be a good idea to prevent small objects dropping through, unless floor tiles are going to do the same thing.

Thanks Gina. I was going to put bits of insulation fabric in the gap, and then put those rubber tiles down. More important things to do first though, like finish the door and get some locks for the ROR. now that I've got some kit in there, I suppose security should come first!

Meanwhile, back to the build ?…...

I had other plans for today (thought I'd better start doing stuff for Christmas!), but thought I'd just tidy up the building site. So, five minutes tidying turned into more than a few hours ……

Cut the remaining pieces of ply to fit around the pillar, which now looks a lot neater. I was tempted to take the floor up and varnish the underside, but knowing it would take a day to dry and there was a chance I may get the scope out later, I decided to leave it and play with the door instead. Sorry, no pictures, but I worked on the baton that will cover the gap on the lock-side of the door/frame. Unfortunately, it turned out to be more work than I thought as I had to progressively reduce the thickness of the baton since the bottom of the door sits a few mm inside the door frame. Treated the baton with preserver and will give it a coat of paint to match the door next chance I get.

The exciting news is that I set-up the scope this evening and had First Light ??. Took ages to find all the bits, which were scattered all over the house. I have to say that the space around the scope is fantastic, and I can't wait until everything is set-up properly. The sky got progressively worse as the evening wore on, but I managed to see 46P and a few of the brighter DSO's through the murk to officially christen the observatory.

Good that you spotted it before cutting precious timber. I've certainly done the same and it's really frustrating when your plan goes out the window. Good luck for tomorrow