Astrokev

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  

Looking brilliant James. Makes such a difference seeing all the walls covered. Hope you can get the cladding on soon. 

3 minutes ago, Gina said:

I started with a Celestron but since have gone for SkyWatcher - same make anyway.

Yes, the MN is a great scope. I chose the C11 for high mag imaging of planets which is a little beyond the MN. Like you though, I have a fairly fast Esprit which is great for wider field stuff  

4 minutes ago, LeeRich said:

Sometimes it can just be down to asthetics Kev can't it?

 

Possibly.

It may be a biased sample, but a few top imagers seem to prefer Celestron - Damian Peach, Pete Lawrence - my guess is that it's not because the OTA looks pretty! The problem with scopes is that not many of us own (say) both a Cel' or a Meade, to be able to do a controlled comparison.  Many opinions are therefore based on a sample of one (not very scientific), but I guess you have to follow the weight of evidence (which still has risk). There is also variation between scopes from each vendor of course, which further complicates the issue.

@LeeRichI was hoping to get the mount and scope set up this afternoon, but the forecast was rubbish so didn't bother. Looks like I'll miss comet 46P at perihelion which is a shame.

Meade - never owned one I'm afraid. I guess they're good scopes (or should be), but I'm more of a Celestron man myself when it comes to SCT's. Just like I'm more of a Nikon man for DSLR's. No real reason.

@JamesFI agree.  As a scientist (or rather ex-scientist) I suppose my method is to analyse a project 28 different ways before I start, consider all the weak or risky areas and try and design those out. This obviously doesn't catch everything, but I enjoy this approach and it works for me. I'm also a trained artist and have always been able to mentally visualise complex concepts in 3D. I love design concept problem solving.

That said, there are certainly a number of bits on my obsy that, with hindsight, I would do differently if I had to do it again (no chance of the latter, once is quite enough!). Likewise, I see many bits on other builds (including Lee's) that I would have done differently. Nothing's ever perfect. This, and the fact that we're all unique individuals with our own tastes and preferences, is what makes life, and this forum, so interesting. Wouldn't it be boring if every obsy looked the same ?

Well done!  Certainly a rare event in my experience!

4 minutes ago, Gina said:

Well said, Kev.  Same applies to me.  I'm not always right either.  I just hope my ideas and project write-ups are useful and interesting and sometimes humourous.

Yes, I really enjoyed your build thread. It may even have been longer than mine!

54 minutes ago, LeeRich said:

It's a forum mentality thing Kev, you either get it or you don't. The statement wasnt directed at you or anyone else in particular, i was just pointing out to Alan that for me I don't take everyone's opinion as "the rule" desipte how "expert" it's put across. As a whole forums are a great place to learn and progress but for some professionals in this field I have dealt with this year say they can also be somewhere to avoid which when learning or needing help can bamboozle the mind lol its the nature of people i guess. ?

"overloaded with hypertheticalism". I must look that up.

Now if you'd said the above the first time, I would have understood what you meant . As intelligent people, we ask for views and opinions of others, and then (and this is the important bit), we evaluate the responses based on our best judgement and other relevant experience, and possibly follow up with further independent research, to achieve understanding. Only then do we decide the best way forward. This may be to follow the advice received, or to follow a different course. Taking anyone's opinion as gospel without engaging the grey matter is not how we learn. I would certainly hope that any opinion I may express is carefully considered and challenged, and not taken at face value as being correct (which it often isn't!).   

44 minutes ago, Gina said:

Looking good Kev

Thanks Gina