ROR wheels and track

[fifeskies]

Part way through making a ROR for my observing shed in the garden.

Thanks to recommendations on this forum I used the excellent "Brundle"  wheels and semicircular galvanised track.

Easy to fit and the roof drifts across with just finger pressure , superb quality compoments

I used this range

https://www.fhbrundle.co.uk/groups/13SWR300__300_kgs_Weight

 

 

 

Yes , I know there's trees in this sky view , but its far better to the south-east , south and the west , no obstructions of any consequence.

Edited November 11, 2019 by fifeskies
note added

[fifeskies]

I have added some pins (bolts) , that engage automatically as the roof closes.

There is a main latch but I can add wingnuts to lock the roof down in stormy weather for extra safety.

 

 

[Alan White]

Nice to see the roof in action, video footage posting was a great idea.

I rather like the curved roof design you are employing,
have I missed a separate build thread?
 

[WanderingEye]

48 minutes ago, Alan White said:

Nice to see the roof in action, video footage posting was a great idea.

I rather like the curved roof design you are employing,
have I missed a separate build thread?
 

Yes me too,  very neat design, I would be interested in more info on the curved roof.... 😀😀👍

[fifeskies]

I have not done a full build thread.

The curved roof is made from curved arc ribs that are 3 layers of 12mm ply glued and screwed together

 

Correction , I used 4 layers as 3 were still too flimsy

 

You can cut a lot of these rib sections from a single sheet of ply.

I used a string and (I think) , a 5m radius to set the first arc , then used first as a template for the rest

Waterproof glue and screwed from both sides.

Main runners are 4 x 2 beams , 2 of them at 90 degrees. Bundle runners bolted direct to the beams

Will post a few pics later as out just now.

Moving roof has a closed arc at one end that was used to set it all square on the tracks

Edited November 11, 2019 by fifeskies
add note

[Gina]

We all love to see build threads on here - me included.  Love that curved roof.

[JamesF]

I like the roof, too :)  A very nice design.

James

[fifeskies]

The roof ribs are fairly stiff on their own after 4 layers are glued and screwed (and allowed to dry)

NOTE : EDIT  I used 4 layers as 3 turned out to still be too bendy and springy

 

 

Moving section is 2.4m x 2.4m   (or 8 x 8 for the traditionalists)

I used standard 8 x 4 exterior ply

One end is braced by 2 x 4 timber and a complete filled plywood arc , this stiffens the roof and discourages it from trying to flatten out.

Depth of the ribs is 75mm  (3inch) which seemed to be enough to resist flattening but not lose too much roof clearance.

 

The ribs were fitted to the moving beams using sections of " 2 x 4  "CLS between the ribs and screwed to the beams and the ribs

 

Over the ribs I covered it with 7mm wall cladding (89mm wide strips) that tongued and grooved together , these were nailed down to the ribs.

This is the internal skin , I wanted wood as metal surface would create condensation.

Over the cladding is a layer of "Protex" waterproof but breathable membrane.

 

Outer layer , not yet fitted , will be sheets of galvanised steel 1mm thick , these get screwed down onto the rib positions with rubber washers under the heads to keep water out

 

heres a photo that shows the basic design

 

Edited November 11, 2019 by fifeskies

[fifeskies]

another photo , shows the internal layer of 7mm cladding going on.

This stiffens the whole roof up before the membrane and (soon to be fitted) flat sheets of 1mm galvanised steel go on as the outer finish

[fifeskies]

Photo of the (North) end of the curved roof showing the solid infill piece and the 4 x 2 cross brace to stiffen the structure and discourage it from trying to flatten.

Both ends used 2 layers glued together . 1 fixed to the roof , the other an extension of the side wall

 

I can sit on the roof and not pop the runners off the track so its actually fairly solid.

 

Whats not clear here is there is a horizontal curved piece to ensure the end stays square to the track , I used the scrap piece left from the sheet after cutting out the ribs.  One piece (at the bottom of the sheet) provided the end cover , the other piece (at the top of the sheet) the horizontal brace.

 

 

at the open end I did add some 3 x 2 cls braces on the last rib , (shown on the cutting template) , to stiffen the open end

 

The open end closes against a curved end wall that slides exactly under the roof profile , till it hits the CLS braces.

 

[Gina]

Galvanised steel will be very heavy.  MDPE rubber would be lighter.  That's what I use on my build.

[fifeskies]

The thin galvanised sheet isn't all that bad and is a simple fix , the roof was designed to exactly fit the sheet size.

I have used it before on a garden shed roof. very hard wearing and zero maintenance

 

 

It has the advantage of reflecting away the summer heat thanks to its shiny finish

 

I did consider the MDPE but in the end decided to use the thin sheet I can get from local blacksmith just round the corner

 

 

 

Incidentally this is a renovation/upgrade of an existing shed/workshop in my garden  , all I am doing is replacing the roof on the old workshop will the roll off version.

Edited November 11, 2019 by fifeskies

[Peter Drew]

Interesting design.  What stops the rolling roof from lifting in wind whilst open or rolling?  Not obvious from the photos.    🙂

[Rusted]

Nice build!

Despite being "shiny," galvanized steel soaks up a lot of heat from the sun. As does shiny stainless steel.
I did some tests of shiny samples of metal sheet in the sun. Aluminium was by far the coolest and lightest.

I had a shed with a 4-6" thick, concrete roof which was unbearably hot in summer. Leaked in the winter.
So I laid flat sheets of thin aluminium from a scrap yard on top and fixed it down around the edges.
This tamed the heat problem immediately. Nor did it ever leak or drip with condensation again.
Rubber pond liner, which Gina mentioned, is affordable, UV stabilised and long lived.
No idea of its thermal qualities but I have used it as a flexible dome skirt.

I second Peter's concern on wind lift in "mid flight." You need hooked retainers to stop lift.

[fifeskies]

I am fitting pin locks to engage in the fully open position in case of wind gusts when open, similar to the closed position pins but at the opposite end of the travel.

 

I had not considered a "mid flight" anti lift to be needed. It only takes a few seconds to travel from one end to the other , and it would not be done when windy. I will only be using it for live observing not remote.

However I think I will look into some kind of arm to travel underneath the track support to give protection when moving as has been suggested as its better to prevent a problem than have to deal with a problem after it occurs.

 

Thanks for the advice , it shows the benefit of forums like this.

Edited November 12, 2019 by fifeskies

[fifeskies]

1 hour ago, Rusted said:

Despite being "shiny," galvanized steel soaks up a lot of heat from the sun. As does shiny stainless steel.

I did some tests of shiny samples of metal sheet in the sun. Aluminium was by far the coolest and lightest.

 

The outer thin sheet will indeed still get hot in the sun      (ask any cat 😃 )

The wood cladding under the sheet will however act as a reasonable insulator preventing too much heat getting through to the inside (hopefully).

I am using the thinnest grade of sheet so it should also cool down fast once the sun goes down.

 

Without the wood (and membrane) layer the galvanised sheet would be a condensation magnet in the cold and turn into a big radiator in the summer.

I am also making sure there is plenty through ventilation under the roof to prevent condensation in cold weather and heat build up in hot weather.

[fifeskies]

16 hours ago, Gina said:

Galvanised steel will be very heavy.  MDPE rubber would be lighter.  That's what I use on my build.

I am not overly worried about weight , the excellent "Brundle" wheels and track seem to glide without any issues despite the use of heavy timber to form the base of the roof. (I have used 6 x 2 and 4 x 2 heavy timbers).

I have used 4 x 300kg wheels , not that I am making a 1.2 tonne roof.

 

The track extends out onto a box section steel braced "pergola" type frame to the side of the existing shed , there is no risk of any sag.

This is also braced by 2inch vertical scaffold poles, all this is hidden in the giant tree rhododendron the pergola has been built over/through.

The advantage of reusing my old workshop is that there is already well established planting to be able to conceal some industrial over engineering.

Its also very handy having a blacksmith in the village who fabricated my steel parts for me.

[Rusted]

You seem to have it all nicely worked out.
Notwithstanding your thoughtful response and without wishing to push you any further in this direction:
Have you asked your blacksmith if he can source thin aluminium sheet?
It is readily available online in all sizes but delivery to a private address can be quite costly.
Metal sheeting, which is insulated from below, is likely to become even hotter.
Baking your timber structure may reduce its lifespan. Which aluminium will avoid.

[fifeskies]

21 minutes ago, Rusted said:

Have you asked your blacksmith if he can source thin aluminium sheet?
It is readily available online in all sizes but delivery to a private address can be quite costly.
Metal sheeting, which is insulated from below, is likely to become even hotter.
Baking your timber structure may reduce its lifespan. Which aluminium will avoid.

I will check on the comparison availability of aluminium

My workshop has mains power so it will be very easy to have forced air ventilation under the roof that can be sensor activated to keep the temperature down , if it gets too hot fans can kick in to blow air through the roof space.

 

I am also wondering about layering some aluminium foil bubble sheet insulation between the metal top layer and the rest of the roof.

readily available and ultra light , just nor sure I actually need it.

 

Edited November 12, 2019 by fifeskies

[Rusted]

I believe that such foil needs an air gap of at least an inch [25mm] to function correctly as a radiant reflector.
Placing it tightly against metal [or anything else] will only form a thin conductor or thin insulator depending entirely on the properties of the material.
In building work it is usually [or should be] sandwiched between well spaced battens to provide the necessary air gap.
No air gap means no reflectance. It would be like expecting our reflecting telescopes to work with the mirror cover still in place.

[fifeskies]

9 minutes ago, Rusted said:

I believe that such foil needs an air gap of at least an inch [25mm] to function correctly as a radiant reflector.
Placing it tightly against metal [or anything else] will only form a thin conductor or thin insulator depending entirely on the properties of the material.
In building work it is usually [or should be] sandwiched between well spaced battens to provide the necessary air gap.
No air gap means no reflectance. It would be like expecting our reflecting telescopes to work with the mirror cover still in place.

was more just thinking of the "bubble layer" being an insulating layer rather than using the reflectance properties

perhaps some foam layer type insulation is a better option rather than paying for the sophisticated multilayer reflectance function then not actually using it

 

 

[saac]

Just caught sight of this thread: real good to see another observatory going up in the Kingdom of Fife, we can coordinate and get a cloud watch going    You are going to notice such a change when you get the observatory operational, good luck with the rest of the build. 

Jim 

[Helen]

I so wish I had negotiated commission from Brundle 😉

You will not regret it - best decision I made, still running smoothly after many years 😁

Enjoy!

Helen