Pier + "Astro Shed"

[ollypenrice]

Although we have four roll off roof sheds here, we also have two full roll offs. That's to say, small sheds which roll off as one unit. This is the smallest possible option and one of the very easiest to build. Because the easy way hadn't ocurred to me I did it the hard way by welding up steel chassis myself. But the easy way is...

1) Find a small ready made sentry box size garden shed commercially available and big enough to cover your scope. Wood plastic, whatever.

2) Cut a plywood base of the same footprint with a slot allowing it to roll around the pier to half way but no further.

3) Fix wheels on the bottom which allow this base to roll up to, or away from, the pier.

4) Assemble your proprietoury shed on this base. Open the doors and it rolls over or away from your scope.

5) Finalize it with an internal drop-down table so it becomes your PC station/warm room when rolled off.

6) Fit anchor points or chains to ensure it is wind proof.

Olly

[Scott]

19 minutes ago, ollypenrice said:

Although we have four roll off roof sheds here, we also have two full roll offs. That's to say, small sheds which roll off as one unit. This is the smallest possible option and one of the very easiest to build. Because the easy way hadn't ocurred to me I did it the hard way by welding up steel chassis myself. But the easy way is...

1) Find a small ready made sentry box size garden shed commercially available and big enough to cover your scope. Wood plastic, whatever.

2) Cut a plywood base of the same footprint with a slot allowing it to roll around the pier to half way but no further.

3) Fix wheels on the bottom which allow this base to roll up to, or away from, the pier.

4) Assemble your proprietoury shed on this base. Open the doors and it rolls over or away from your scope.

5) Finalize it with an internal drop-down table so it becomes your PC station/warm room when rolled off.

6) Fit anchor points or chains to ensure it is wind proof.

Olly

this is kinda what I did. video is mid construction (I really should make a finished version ).

 

[Shibby]

It seems a certain lady named Doris has tried to help me remove one barrier to my build!

 

[Ouroboros]

Result!  It's an ill wind that blows nobody some good, as they say. 

[iapa]

On 2/23/2017 at 19:48, Shibby said:

It seems a certain lady named Doris has tried to help me remove one barrier to my build!

clouds and silver linings?

[Shibby]

I have more questions about my planned Roll-over roof observatory if anyone could help?

I've been thinking about polycarbonate sheets for a lightweight but firm roof - I could then cover this in a rubber roofing membrane. Does this seem like a good / bad idea? I've heard stories of sagging plywood that I'd like to avoid if possible. Also, it'll be quite a large + flat roof.

Damp-proof membrane: I am thinking of the following, from ground up: Hardcore, thin layer of sand, DPM, sand, mortar, paving slabs. I aim to have the slabs slightly above ground level to prevent water collecting. Is the the right place for a DPM? Do I really need one? I'm ensuring that the base is only a tiny bit larger than the shed.

Behind the shed, I'm leaving a gap of around 3ft. Shame to lose the garden space, but will make it more accessible and also prevent the water run-off rotting the fence behind. (The pent roof slopes backwards). Do I need to maybe put down weed barrier & gravel, or do something else for drainage?

Thanks for any advice

[Davey-T]

Not sure why you want to cover it in rubber, which is quite heavy by the way, you can get opaque polycarbonate in white and bronze if you don't want it see through.

I'd be inclined to weld up a pitched roof frame out of 1" square steel tube with overhang on the sides and track mounted on the outside of the shed.

You can get all the stuff needed to assemble polycarbonate roofing, profiles etc.

Dave

Something like this

[Shibby]

Oh can you? Nice. I have googled for opaque sheets before but only found tinted. Perhaps I didn't search hard enough!

I think perhaps you're right about having the runners on the outside - I keep going back and forth between this (similar to my previous idea here) and the simpler, but potentially less weather-proof, approach of placing the runners on top...

[Shibby]

The hardcore/MOT and sand arrived today. Anyone have opinions on the DPM before I lay it down?

Quote

Damp-proof membrane: I am thinking of the following, from ground up: Hardcore, thin layer of sand, DPM, sand, mortar, paving slabs. I aim to have the slabs slightly above ground level to prevent water collecting. Is the the right place for a DPM? Do I really need one? I'm ensuring that the base is only a tiny bit larger than the shed.

 

[Davey-T]

You could try to raise the base above the surrounding ground level and slope the edges away for run off.

Mine is on a similar base with no damp course but has a solid plastic floor.

Dave

 

[Carbon Brush]

I have been away from this topic for a while. I do like the idea of a polycarb panel roof. That means you just need a strong frame around the edge. I used some (low cost from Wickes) panels on a garden shed roof recently. In this case It was in the form of a clear panel leaving a reasonable amount of original wood around. They were easy to work with and very light. Should my observatory require serious roof repairs in the future, I would definitely  think polycarb. We have all seen them used for conservatory roofing.

The only potential downside of polycarb, that I can see, is security. Using low cost/low weight panels, it would be easy to break in. But there are ways around this.

HTH David. 

[Star101]

I have been looking into the ROR thing. I am looking at these for runners and rollers to help with the roof. Imagine UPSIDE DOWN!!

I was thinking this would help keep the roof on when the wind gets up!

http://www.fhbrundle.co.uk/products/41K1503__Light_Duty_Top_Track_3_Metres

And the rollers

http://www.fhbrundle.co.uk/products/41MP150__4_Wheel_Light_Duty_Hanger_K150

Expensive, but should help keep the roof on.

[Merlin66]

I used C purlins with 100mm wheels on my version of the ROR.

It was an adaptation of an existing workshed.....working well, no issues no drama.

 

[Carbon Brush]

Wow. This runner arrangement makes my construction look like something from Messrs Heath & Robinson.

I used decent size nylon fixed castors on the roof. These run in a half round PVC channel.
This is a posh term for PVC waste pipe cut in half lengthways and screwed to timber.
9 years on, still working well.

There are many ways to keep the roof from blowing away. I worked on the basis that if a gale is blowing, I'm not going to be opening the roof.
It therefore only needs to be held down when closed.

Long bolts are fixed to the 'moving away' end of the roof. These point back towards the shed, fitting into holes in the top of the shed frame.
When the roof is closed, the bolts prevent any roof lift.

At the end of the roof that moves from one side of the shed to the other, I have some L shape brackets pointing down.
When the roof is closed, holes in the brackets engage with bolts fitted through the top of the shed wall.
This course pevents roof lift. A benefit is the L brackets provide travel stops so the roof can't move too far if the motor drive loses datum.

Adding a couple of washers and wing nuts to the bolts prevents roof slide and gives security.
 

HTH David.

[carastro]

I am not sure what your budget is for this build, but are you aware that Ian King sells ROR observatories and will install as well for an extra £500.

I only mention this because you seem a bit dubious about your building abilities.  

Carole 

 

 

[iapa]

2 hours ago, carastro said:

I am not sure what your budget is for this build, but are you aware that Ian King sells ROR observatories and will install as well for an extra £500.

I only mention this because you seem a bit dubious about your building abilities.  

Carole 

 

 

The 8' x 8'@@2250 is OK

The £400 return trip plus overnight charges put that option beyond budget.

Maybe I need to move the land of the Sassenach

Or practice woodwork LOL - then again, by the time I feel comfortable I'd have spend 5x that cost with no real result  

[Shibby]

 

On 10/03/2017 at 23:22, Davey-T said:

You could try to raise the base above the surrounding ground level and slope the edges away for run off.

Mine is on a similar base with no damp course but has a solid plastic floor.

Dave

 

That's a really neat solution - thanks, I'll aim to do something similar with the mortar when I come to lay it.

On 11/03/2017 at 23:48, Merlin66 said:

I used C purlins with 100mm wheels on my version of the ROR.

It was an adaptation of an existing workshed.....working well, no issues no drama.

 

I do love the look of your fantastic obs - it's not a million miles away from what I'm trying to achieve.

15 hours ago, carastro said:

I am not sure what your budget is for this build, but are you aware that Ian King sells ROR observatories and will install as well for an extra £500.

I only mention this because you seem a bit dubious about your building abilities.  

Carole 

I can certainly see the merits of that, but I'm too far down my own path now - no turning back!!

[Shibby]

On 15/02/2017 at 13:50, Carbon Brush said:

...When running 12V power from shed to pier...

More questions (sorry)...

I've got the drainpipe etc and will purchase heavy cables. What kind of power supply will I need? Will this do the trick?

http://www.maplin.co.uk/p/moonraker-375w-switched-mode-dc-variable-voltage-compact-bench-power-supply-n87jn

Does it have enough outputs? Can I run multiple 12v devices from a single output? (would that be a bad idea to allow certain devices to potentially draw more current than they should be?) Sorry for the noobish question! Is there a limit to how long the DC cables can be?

[Davey-T]

Should be man enough, it's worth making yourself a splitter box with enough outlets for your needs connected to the screw on terminals.

DC  doesn't travel as well as AC and needs heavier cable, if you do search you can find voltage drop tables, maybe someone has a link.

Dave

[Carbon Brush]

Further to Dave's comment. Yes there is plenty of power in reserve. However, an external distribution and protection network is required.

If there is a short circuit in the wiring, or your kit, what happens?
Well the shortform data on the web page doesn't actually state the output will withstand short circuit without damage.
If it won't stand a short, it could well fail.

 

I would establish first if the power supply is short circuit proof.
I wouldn't bother asking Maplin. Their technical advisors are, in my experience, less than useless. Find out the direct way.

Stick a reasonable load on the output. Say a car brake light, or headlight. See that the supply is 12V (or whatever is set) and providing a little under 2amps for a brake light, or 5amps or so for a headlight.

Now the exciting part. Put a piece of heavy wire straight across the output terminals. Something the thyickness of cooker or shower cable.

The bulb will be off. Voltage will show near enough zero. Depending on the type of overload protection, you might see 30 amps and more on the meter, or it might shut down to zero.
If there is 30+amps, hang your nose over the case and sniff for burning. Leave it like this for a minute or two. Unless smoke issues forth!

Remove the wire short circuit and check the bulb comes back on. If not, turn the power off/on and see that the supply recovers.

If you have broken the supply, send it back for refund. If it is OK, you can proceed further.

This involves thinking about a distribution network with small value overloads/circuit breakers/fuses for each item of kit.
Why distributed?

Suppose the power supply happily provides 30amps and more into your load. That is the sort of current that can be used when welding thin sheet metal.
The thin wires on things like mount power cables become effective heaters to the point of melting plastic insulation.
If there is a fault within a mount, you could well end up with cooked components that render the drive a toasted write off, rather than repairable.
If you had protection that trips at a couple of amps for a mount, you won't get the red light of burning circuits if there is a fault!
One example is the grotty plastic DC plugs used by many mount manufacturers. Leave one of these passing 30 amps and more for a minute and it will melt, or catch fire.

A power distribution and circuit protection network is not difficult to build with only basic soldering skills.

HTH David.

[iapa]

Great advice - for someone who has done this before, or has a relevant back ground.

What is your advice for OP when the ;heavy wire' welds itself to the terminals? Run?  

Lean over a lead acid batter and sniff for burning?

This isn't new to me, but, may freak some people out?

[ollypenrice]

On roof materials my own decision from here on in is nothing, ever, under any circumstances, other than corrugated steel. It is best by a million miles. Firstly it is very long lasting and absolutely waterproof. Secondly it doesn't degrade under the effects of UV. It doesn't sag. It doesn't tear. Because it doesn't tear it can be bolted down with absolute confidence. It won't pull through the bolts. The wind won't lift it.

Of our six sheds, four had corrugated steel and are still going strong, the oldest after thirteen years. Two have synthetic corrugated roofing sheets and these have done all the bad things that I list the steel as not doing. After only a few years they all need replaceing - with steel!

You can use the smart kind like Merlin's. I've just gone for the bog standard stuff from our builders' yard.

(I went for fibre-concrete for the warm room part to keep it cooler. (Erm??)

Olly

[Shibby]

1 hour ago, ollypenrice said:

(I went for fibre-concrete for the warm room part to keep it cooler. (Erm??)

Looks bomb proof, is this where La Resistance was based?

Food for thought, thanks. How heavy is the steel - I need to keep it light if possible. I do like the way you've achieved roll-over. Does any rain get in under the seam, though? (If you get any!)

[Merlin66]

Tin roofs are OK, but sometimes in a strong storm things happen!!!!

[Shibby]

14 hours ago, Carbon Brush said:

Further to Dave's comment. Yes there is plenty of power in reserve. However, an external distribution and protection network is required

...

HTH David.

Thank you kindly for all the advice, I'm gonna take my time with this build and hope to get it right!

1 minute ago, Merlin66 said:

Tin roofs are OK, but sometimes in a strong storm things happen!!!!

Ouch, is that yours?? I guess tins are meant to be opened! Too soon?