Astrokev's ROR - The Build

[RayD]

Great job, Kev.  Looks really tidy and is going to last a very long time.  Know the feeling with the injury, much blood was spilled during my build, but it is soon forgotten when the roof rolls back and you just image away.

Really enjoying sharing your build with you.

Edited June 7, 2018 by RayD

[swag72]

This is coming on really nicely Kev  Love watching the progress ??

[Astrokev]

Spent the morning checking out a beautiful second-hand scope. My will-power collapsed and I collect it next week. Happy bunny!

By the time I got home the day was largely gone, but found time this evening to make a bit more progress. OSB cut and screwed in place on the warm room roof. Hope to do battle with the EPDM tomorrow. Have to admit to feeling a bit nervous; never used it before and the bottom corners look a little tricky. Contact adhesive seems pretty unforgiving if I don't get it right first time. Watch this space...

 

Edited June 8, 2018 by Astrokev

[Alan White]

Resolve or will power with a used scope, what’s that? I don’t think it exists does it?

[Astrokev]

Well, Saturday was wiped out due to my daughter hurting her ankle and us having to spend the morning waiting in-line at the walk-in medical centre. Fortunately she's OK and will fully recover in 4-6 weeks.

So, this morning was the big day - unwrapping the EPDM and getting it stuck on the warm-room roof.

Here's a picture of the said EPDM stretched out on the lawn to check it over. Lovely you might think - and that's what I thought until I got the tape measure out, just to check. They wouldn't send me the wrong stuff, would they? Well, it seems I was wrong, and yes, they have sent me a different size to what I ordered.

I ordered a length off of the 3.53m wide standard roll. They got the length correct, so are able to use a tape measure, but sadly they seem to have cut it off of the wrong roll, sending me the standard 3.05m wide material by mistake.

How cross am I? I'll leave you to figure that one.

To add insult to injury, in a separate order they also sent me a 9" roller when I ordered a 4" mini-roller. I forgave them that as it's only a few quid and not worth the hassle of returning it, but a >£200 EPDM order is a different thing.

So, tomorrow I'll don my Mr. Angry hat and there'll be a very irate phone call to Rubber4roofs!

 

[Gina]

Ooooh!!!  That's bad!  Good job you checked before you hauled it up onto your roof!  No doubt they'll be all apologetic but a replacement will still take time to deliver.

[Astrokev]

1 minute ago, Gina said:

Ooooh!!!  That's bad!  Good job you checked before you hauled it up onto your roof!  No doubt they'll be all apologetic but a replacement will still take time to deliver.

Yeah, it's the lost time that annoys most. Even though I'm now retired and theoretically have more time (I honestly wonder how I ever found time to work before retirement), trying to align free time when the weather is decent isn't easy!

[Gina]

No, that's the problem as usual - the weather!!!

[Astrokev]

Not much action on the observatory today then after all, but I did put up a bit more of the breather membrane around the warm room. Beginning to look quite cosy in there now and starting to get a feel for what it will be like when it's fully walled-out.

The full obsy image looks a bit of a bomb site. The EPDM on the roof is a patchwork of off-cuts from last year's project of relining the pond and is just to keep dew off the roof. Taking no chances! The bent uprights in the middle pic are camera distortions - honest!

Edited June 10, 2018 by Astrokev

[JamesF]

Very frustrating about the EPDM.  Hopefully they can sort it quickly.

James

[Astrokev]

Rubber4roof update. 

The very nice man was hugely apologetic (as expected) and is to send out the corrected order today. 

I guess you can't expect more than that. 

Looking forward to cutting some rubber ?

[yesyes]

Glad to got it sorted.

Did you get to keep the wrong sized sheet? I kept all my offcuts and found them quite useful for all sorts of things. We have a small piece under the dog's food bowl to keep it from sliding, a larger piece as a protective mat on the workbench and so on. ;-)

[Gina]

Yes, I've found lots of uses for my offcuts too.

Good to see you around again Chris

Edited June 11, 2018 by Gina

[Astrokev]

46 minutes ago, yesyes said:

Glad to got it sorted.

Did you get to keep the wrong sized sheet? I kept all my offcuts and found them quite useful for all sorts of things.

Sadly not Chris. TNT collected the wrong one a short while ago. 

There will be some left overs, and I've got a fair bit left from my pond revamp last year. I'm sure these will come in useful for sealing the nooks and crannies to keep the worst of the weather out ?

[Astrokev]

I've been playing around with how to fit the EPDM around the corners of the warm room roof. I believe the traditional way is to use folds similar to when making a bed. Unfortunately, this doesn't work with my design, since I want to cover both the roof and the adjacent rail beams with a single piece of rubber. Because the roof slopes, the angles of the roof and rail are different and trying to fit a single piece snugly around all the timber just doesn't work. Despite playing origami with some EPDM off-cuts, I've concluded that it's impossible to get a good fit around the OSB without cutting into the corner, which would obviously risk water getting to the OSB. I should have considered this more fully when I designed the roof.

So, here's my solution. I hope to first fit a corner piece (2nd pic) to give good protection of the roof edges ( I say hope because once the rubber is glued-up it may all go horribly wrong when trying to fit it into the c.2mm gap between the roof and the rail). Then the main EPDM sheet will be cut and folded as shown. It's difficult to illustrate this clearly in 2D but hopefully you can see what I mean in the sketchup diagrams and the feeble photo of me trying to hold the rubber with one hand. The end result gives much better protection of the OSB - I hope.

Edited June 11, 2018 by Astrokev

[Gina]

I had funny corners on my observatory too.  Some of my rubber does some very strange contortions! ?

[JamesF]

I think your method is sensible, Kev.  I can't realistically see any moisture getting in that way.

James

[Astrokev]

Well, the replacement EPDM has just arrived.....

and now it's started to rain. The BBC weather app gives a 2% chance of rain in the next hour. Huh! My luck is doing too well at the moment ?

[Kev M]

In the process of planning a roll off roof myself and I think this is a wonderful write up.

Just thought I would say well done so far and I hope you dont mind me borrowing some of your ideas ( well most of them actually ! )

 

Kev

[Astrokev]

5 hours ago, Kev M said:

In the process of planning a roll off roof myself and I think this is a wonderful write up.

Just thought I would say well done so far and I hope you dont mind me borrowing some of your ideas ( well most of them actually !

Thanks Kev, that's kind of you to say.

Feel free to borrow as many ideas as you want - the reality is that these are not really my ideas at all, as I pinched most of them from other builds! I think that's the whole point of this forum - to share ideas and experience so we all benefit. I have certainly been inspired by many builds over the last 5 years or so and have been cherry-picking ideas from others along the way for when I eventually (and it took some time for me to start in earnest) made a start. The main build that inspired me most was @yesyes, and I recommend you dig out his build from a few years back, but others include @RayD, @Gina and @Malc-c. All excellent builds.

I'm enjoying the project and like to share as much as I can. If others enjoy following my build as much as I've enjoyed following others, then job done ?.

[Astrokev]

The weather has improved slightly so I had to roll out the EPDM to check dims. Good news is that all is well - in fact it's a little larger than I ordered so should remove risks from my measurement errors. I've cut the piece I need for the warm room but will probably leave this until tomorrow now, when I have more time. I'll mark up the roof this afternoon and finally decide which areas I'll use contact adhesive and which WBA.

A question to those who've used EPDM - it comes with a fair amount of powder covering the surface which they say is  to make handling easier. Does this impair adhesion at all, or should I try and remove it before applying adhesive?

Thanks

[yesyes]

I did not remove the powder and all was (and is) fine.

Remember you need to put the EPDM on the roof for a few hours, ideally in sunshine (yeah, I know... :-) ) and then not move it before glueing. It gets a little softer in the "heat" and takes the shape of the roof. This also smooths the areas where it was folded (mine actually came on a roll, if I remember correctly).

 

[Gina]

Mine was folded so needed plenty of settling time.  Think I left it a couple of days.  Then to glue it I lifted one end and rolled it back half way, applied glue as I gradually unrolled it, smoothing out any bubbles as I went (important).  Then, having done one side, rolled up the other etc.

[Astrokev]

My thoughts are now returning to the rolling roof. Once the EPDM on the warm room is down (hopefully tomorrow), this is the next job. This post is to ask folks views on whether the design shown below will be rigid enough across the width of the obsy. Pic 1 is a general 3D view. Pic 2 is a sectioned orthographic view looking along the apex, with the side panels removed for clarity.

Key = Parts shown in green, yellow and blue are the rolling roof. Red parts are the position of the V wheels.

I've only shown a couple of green joists for clarity. In total there will be 6 or 7 (haven't decided yet).

The pale grey timber is the fixed dividing beam separating the warm and scope rooms.

The yellow and blue beams span approx. 2.3 m unsupported apart from at their ends.  For the yellow beam, my plan is to use 2 lengths of 45x95 timber screwed together, making a beam 95 (vertical) x 90 (horizontal) in size.

For the blue beams, one is 120(V) x 45(H), the other 95(V) x 45(H)

Now that I've felt the weight of the EPDM, although the load will be spread out, I'm concerned that the beams may bow in the middle over time. The separation between the grey dividing beam and the yellow roof apex beam is about 30mm, so there's not much room for movement in the beam if it does start to bow.

What do folks think?  Do I need to consider a different design to increase rigidity and reduce risk of bowing?

Thanks

[JamesF]

My slight concern about your roof design is that "stuff" can roll off it into the obsy whenever it's open or being opened or closed.  I might be tempted to put a raised lip on the end of the slope to deflect anything that has run down the roof to the sides.

I may, of course, be worrying about nothing

James