Bouncing ideas - Roll off roof observing shed.

[Ian Robinson]

Looking at this , sick of lumping about and polar aligning my scope , was bad enough when I was using the 10" newt on my old CG5 on a steel tripod, but the Atlux is easily 3 or 4 times heavier than the old GEM (looking at head, with no counterweights only).

So , to preserve my back and avoid straining something, and make my time at the scope more productive I'm seriously looking at a garden shed that I will have modded so roof can be rolled off so I can set up the scope on the new GEM and also my old GEM on separate "permanent" pedestals all "under one roof.

I was considering putting my roll off roof observing shed right next to my garage (with a roll off skillion style roof and the north wall of the garage forming one wall of my shed , and having my piers footing below decklevel with my piers protruding through the deck ,with a deck built around the piers and above the ground as my floor (level with the top of my garage slab) but it looks like a suitable timber deck (3mx3m in this case) will be prohibitively expective (way outside what I am prepared to spend).
I may return to this but with a concrete slab rather than a above ground deck but I will loose a big bit of the low southern sky with this arrangement while gaining some more low north and west sky .... gain some loose some .... oh for a flat horizon or being on the top of a hill somewhere....

So I have reconcidered , and am now looking at a using a concrete slab as my base despite concretes poor thermal properties.

Situation
I have a very poor northern sky (high horizon, obscurred by the neighbour's garage somewhat, and badly light polluted (that's the general direct of Charlestown Square (if you live in Newcastle you know that place is lit up permanently like a Xmas tree)), my southern and Eastern sky are not too bad (considering I am in basin surrounded by hills) , and my house obscurs much of the western sky (but blocks a street light pretty much right infront of my house).
My lard slopes downhill from w --> e ( there's a 12" drop over 6m at my garage which typifies my back yard.
So I have little choice but to orientate my shed eastwest (long axis) and I am considering a 3.8mx2.4m shed at least or maybe a 3.8mx3.3m shed (depends on concreting costs , most likely choice due to space limitations in the yard is the smaller one).

I think I'll arrange the roof to roll off to the north (will need to be modded to effect this by adding a horizontal cross rafter at each gable end (see sheds c/- h0ughty ... thanks mate for finding that ....) rather than to the east which is the other possible direction but will require more materials.

I am hoping the total cost of my shed will not go much over $1000 including slab .

Those who gone down this path already ,
a) do you think these shed sizes are adequate or too cramped for two setups (one with a wideange sky patrol type camera platform based on the old CG5, one with the 10" f4.6 newt on the Altux) ?

b) has anyone bothered arranging their roll off roof shed so the SCP is always above the southern wall of their shed (once properly polar aligned you never need to see it again , though comets low in the southern sky sometimes come along and they may be lower than the SCP) .... thoughts anyone on this ?

c) parking the scope when not in use , how far is considered a minimum desireable clearance so the roof clears the mount and tube and what ever is on the tube safely when the roof is rolled back on , or off ?
ie my OTA has an OD of 316mm, so when parked horizontal , is a clearance from the tube centreline of 200mm adequate ?

(assuming nothing on the tube will project above top of the tube in this orientation .... :shrug:....Probably a dum question but it will govern the max height of the pier the Atlux will live on assuming I keep a big part of my low southern sky below the SCP.)

All this assumes the gable roof sheds I am looking have roofs that are light and I convince the company who makes these to make roof so it can be constructed as a separate module (that is reasonably rigid structurally ) from the shed and can be simply lifted onto the rails when these are ready. (C H E A P L Y ! !)

[Merlin66]

Answers:
a) Bigger the better. I've got an 12" LX200 on a reduced height HD tripod in an 8' x 6' tine shed. Fits, but an extra couple of feet all round would be nice!
b) Doesn't matter; once you've set up; who cares!
c) The roof on mine just clears the 12" with a set of 120mm guide rings/ ED80 on top, when horizontal. Angles of dangles and limited horizons.....

[GrampianStars]

expensive ??? :whistle: about $120 all up from a timber merchant (wholesaler) in hardwood not the big green (B's)
about 4 hours work to build :thumbsup:

[Ian Robinson]

Well based on a quote my mum got to build an elevated one out the back of house (hers was 6mx3m and was to be 6 ft of the ground at the house wall (oooo .... handrails handrails needed) and was to incorporate her existing back stairs), she was told at least $10k so it wont happen.
So I presumed a 3mx3m would be maybe 3/4 this .... it's mostly labour .... but based on your response - 'I'll head to Mitre10 at Warners Bay (bugger Bunnings - I actually want someone to give some service) and I'll now make serious enquiries on that total for materials costs , then I'll chase up a local handyman (I don't have a lot of carpentry power tools , just a jigsaw and handheld circular saw) for a price to construct it ....so might go that way yet.

[rmcpb]

You only need your deck to be on low stumps which is an easy setup compared to 6' up! If you do it yourself then its relaively as cheap as chips compared to the scope setup and the rest of the observatory.

[Glenhuon]

You don't need much else to put it together Ian. Get a decent handsaw, Battery Drill and screwdriver bits, a hammer and a tape measure and your away.

Bill

[Ian Robinson]

Sounds like trip to Bunnings and Mitre10 may be in order tomorrow to talk with them about cost of materials for the off-ground deck for option A.

Still waiting on the concreter to quote the slab for option B.

Anyone have any experience with this stuff http://www.apsversiclad.com.au/pdf/brochure.pdf
Their Spacemaker 1000 insulated steel roofing looks like a great option .
Their Spacemaker modular wall panels look very interesting too (even better , they are also insulated).
==> option C ??

[Ian Robinson]

Re Option C :

Sent this email last night :

I am looking at installing a free standing shed with a roll off roof. This will permanently how two telescopes on permanent piers.
the size and arrangement is shown in the attachment.
The shed I am interested in will be 3.78m long x 2.34 wide with wall panels 2.13m high. I would prefer each wall except the "front" wall to uninterrupted (no windows), the front wall will only have a door (sliding is preferred).
The two end walls will support timber rails that the roof will roof off along.
There is no need to make provision for AC power - everything will be powered from 12V batteries .
The roof I require is a low pitch gable roof and I would like it supplied prefabricated if that is practical and it is light enough.
The materials I like are ;
walls = 38mm think metal clad PANELINK
roof = SPACEMAKER 1000 + what ever structurals is needed.

Q1 ; how heavy will a pref gable roof (400mm pitch) be ? how much to prefabricate it ?
Q2 ; how much to manufacture the 4 walls required + structurals ? How heavy will each wall be ?
Q3 ; how long from order placed to supply ?
Thanks ian Robinson

]Response : Hi Ian
]I have attached a price list and specs sheets to help you with your enquiry – we only manufacture the panels you would have to contact a builder to help you with the installation and what panels and extrusions would be required, the turnaround time from order to supply is normally around 4-5 working days for wall panels and 7 working days for roof panels. Spacemaker 1000 roof is aprox 8kg per sq meter and panelink panels are aprox 4kg per sq meter.
Hope this information helps – if you have any further queries please do not hesitate to contact us.
Regards,Rhonda Mort
APS VERSICLAD Pty Ltd


They provided attachments including a detailed price list (too big to attach ... if anyone wants it .... email me and I'll share it).

Costing estimate base on info provided to me for Option C

A prefab gable roof ??

Spacemaker 1000 roof sheets 50mm thick (uninsulated steel roof sheetiing gets hot and reradiates significant heat , these are insulated .... this will keep the telescopes and slab cooler in summer a definite plus I think , the sheets are also very strong - you can walk on them up to 4m span !!! - so if the apex is strongly joined together , minimum structural reinforcement is required ?) are $86 per linear m , they are 1 m wide.
A few calcs reveals the prefab Spacemaker 1000 (2.4m x 3.8m x 0.2m pitch) roof will weight in at 74kg if a pitch of 400mm is used and sheeting works at about $800 (making queries on cost for a prefab roof (might be another $100 say for assembly of the pref unit ??).
Using standard Panellink panels (2.4m x 1.2m) the above will produce a roof with 100mm over hang on each end (enough for the external rails ??).
At 75kg it's a 2 man (probably a 4 man job lifting a pref roof this size to the rails about 2.2m off the ground unless I get cleavour :D , I'm not a gingerbeer for nuffen !:whistle:)

Easiest end pieces are marine plywood I think both cut from one sheet.

The insulated walls the bee's knees option .

$70 / lin m (comes as blanks 1.2m x 2.4m x 36mm thick (?)) for plain (Zn coated steel on both sides (also insulated).
I figure 9 standard sheets (cut) with (provision for a 1.2m wide entry door) are needed if I go for a shed 3.6m x 2.4m makes it easier). (If 9 sheets are needed = 24 lineal m = about $1700 for walls panels (uninstalled) made from basic Panellink panels .... a tad pricey but would be very nice.
Poor mans walls option : construct walls like a panel fence or simply build a timber or steel framed wall and Hardyplank it. Food for thought (visit to Mitre 10 or Bunnings worthwhile).

Door

Maybe a slider or hinged entry door made from a varnished or painted marine plywood sheet (1" thick) will suffice.

Thoughts anyone ?

[Big Dave]

I built mine myself. Not to hard and under 1000. I even saved space by building it over the water tank.

I also have the Atlux an no northern views.

I have some pictures on the web, if you want to know more look at the 'roll off roof' group on Yahoo groups for plans or PM Me.

http://www.big-dave.com.au/Observatory.htm

- Dave

[Ian Robinson]

Dave,

.... you did a great job.

How tall did you settle on for your wall height ?

the flat slidding roof looks pretty good.

Is that roof the same stuff I'm looking at (SPACEMAKER1000) ?

I sent off my faxes to the local Bunnings and Mitre10 to ask for quotes on materials including prefab timber wall frames this avo .

[Bassnut]

Ian. The single biggest influence on my imaging was megadata, what ever you do, try to allow roof closeing in any scope orientation, so that you can fit a simple motor/rope/timer close in the future, to allow imaging long after youve gone to bed.

[Ian Robinson]

I remember your discussion of how you built your observing shed .... I must admit, I'm moving in a similar direction.
Bassnut's observatory link http://fredsastro.googlepages.com/observatory.

Your off-the-ground platform floor idea inspired my Option B (shed butted up against my garage).:D Sloping back yards are a bummer.

Good engineers aren't scared of using other people's ideas if they are good ideas.

I'm still waiting for the concreter who subs for the sheds place in Cardiff to do a quote for my slab .... he's pretty reliable (not) by the looks of it. Think I'll try someone else for a concrete slab quote. Memories of my experiences when I had the double garage built ..... concreter turned up, dug about a bit and disappeared for 4 months and was always coming back next week , wound up sacking him and getting someone else and told him he could kiss goodbye any payment from me for the work he'd done .... I never paid him.

Yet to visit the sheds place too.

Anyone in Newcastle area know of a good , cheap , reliable concreter ?

[Bassnut]

Why not do the concrete pier yourself?, its not hard. Really, rio is not required.

[Ian Robinson]

That's something I am definitely concidering , I need two .

I'm concidering using an offcut of PVC water pipe (I happen to have in the rafters) which is about 8" OD as the mould , and using quickset cement mix (if I can it with fine gravel in it) and dumping the dry cement mix into the pipe buy the bucketful , hitting the mix with water from a hose to soak it, and then repeating the process until the pipe is full of damp cement.

(Did this when I erected my back fence (dug a hole big enough to take a full bag of cement mix , stuck the RST fence poll in , leveled it , and dumped the cement mix in dry and hit it water until the cement couldn't soak up more).Did this for each fence poll.

Biggest disadvantage of a concrete fixed pier is it is there forever , not future proof. I can live with that.

[Big Dave]

Quick stats;

ROOF : 2 Sheets (Seconds), white 0.55mm Colourbond
ROOF LINER : Insulating Foam from Bunnings (Stop Condendation)

ROOF TRACK : 100m Lipped Chanel
ROOF ROLLERS : 4x Automotive bearing
ROOF FRAME : 25x25 Box tube steel

WALLS : Treated pine decking -outside, Inside AC Sheet
HEIGHT : 1.8m Floor to bottom of roof (I dont need to duck). With my electric pier I can nearly see the horizon.

FLOOR : Cement (1m cube below pier) and lino to slow dust

If you keep it simple it is not that expensive.
I have seen some sheds posted on the Yahoo group, they all seem to weak as the roof is part of its structual design. If you modify it you will need a lot of bracing to compensate. Also they are not as easy to secure.

- Dave.

[tempestwizz]

FWIW, I've built a "reflex" roll-off roof(?) I have effectively divided my available 3.5m by 8m ground space into two. One half is set up for the pier and scopes, while the other is my 'control room'. The control room has a fixed gable roof, but the viewing room has a higher sliding roof that slides back over the viewing room roof. ( I did/do not have space to have the roll off section hanging out one side when viewing.)
Also my horizon is not particularly clear, so my concrete pier is quite tall, and I've built a raised timber platform around it to walk on. Generally though imaging close to the horizon does not produce good results.
Built in stages, it was not overly expensive for me, I'm guessing about $3k all up.
A couple of pictures attached at mid-build.
I can provide more detail if interested.

BC

[Bassnut]

Rio?, nup, its hardly an industrial application. My quickset pier does the job, period. There is much angst on the merits of steel/concrete piers. Steel needs subbies=expensive, concrete=do it yourself. Steel is good for removing/low thermal mass (yawn, do you have a 32" RCOS, where its makes a difference?). A concrete pier is way strong enough. Have you heard of a collapsing pier due to no rio?

[Ian Robinson]

Saw your comment re no rio. :thumbsup:

Just wondered.

[Ian Robinson]

Steel fencing stuff on the outside of the walls is an option , damned easy to attach to timber , also considering Hardyplank.

Wife tells me the shed better not become an eyesore , she wont be happy if it does.

[Ian Robinson]

Another option for the roof : a convex curved roof.

One option I am thinking about is using factory formed convex Zincalum roofing in my shed's roof .... this is better than a sprung convex roof I suspect , wont pop and ping as it expands and contracts like sprung roofs often do - (more rigid than straight roofing sheets) , I need to check that with the supplier (as it will naturally be convex curved , makes the construction of a rigid and strong roof much simpler I expect).

ie see attachments .

Anyone had any experience with this type of roofing ?

[Ian Robinson]

Concreter from shed mob showed up (at last) , quoted slab $1200 if I go to 3.9m x 3.3m slab , gravel fill and made to building stardards .... ouch !!!
Looks like overkill to me ----it'll only have two telescopes on piers in it and maybe a desk , a lockable cabinet , and a chair inside.

The chap who came this avo is a bit expensive I think and did the hard sell on the steel garden style sheds for the company he works for.

Called another concreter who I'll ask for quote for the same size slab done REAL BASIC.

I can get 4 cum of readymix for $850 (concrete only).
Seriously considering doing my own formwork ( frame only) and just filling it with readymix , even if I pay someone to smooth out and level the top of the wet readymix when layed.

(gives me about 0.7m minimum walk around room from the business end 10" OTA when horizontal , if I go stuck with a 3.8m x 2.4m shed will have only 0.4m minimum walk around room , tha's a bit tight I think .... OTA not been reassembled yet - guessing COG will be about 1/3 way from bottom of tube .)

Pegged out the spot (it will dominate the yard !! if the roof rolls off towards towards the north boundary fence) , time to reconsider LOCATION and ROOF-OFF direction I THINK.

Now thinking along lines of placing the slab nearer my north boundary and rolling off to the either the east or west.

A timber framed 3.8m x 3.2m shed , steel low pitch gable steel roof or convex (not sprung) roof , clad with zincalume steel sheeting or Hardyplank is looking promising.
GEMs on concrete piers is looking better and better too.

Can't be that difficult to get the treated pine cut to length and assemble (nail together) the wall frames , still no quotes on prefab wall frames yet...

[Big Dave]

Concrete is easy to do yourself if you pre-mark all your levels and have some basic tools. Like any DIY, the more you do yourself the better the project pride!

Also don't forget to run any pipes under your slab out to your pier before you concrete if you dont want to trip over leads later. I used a 50m pipe so I could get cables with plugs on it threaded though and also a power point near the base of the pier is handy!!

I attached some pics of mine including the roller section if anyone is interested.

- Dave.

[Ian Robinson]

Not wrong on the pride thing .... gotta give this more thought before I start spending money .

Looking at walls 1.7m tall .... I'm a short bugger so that gives me at few inches to spare.

I really like the curved steel sheet roof idea too and am thinking of incorporating it into my design rather than a low pitch gable , skillion or even a flat roof.

I've rejected the steel garden shed (basic shell) idea, not enough structural strength in the wall structure to support the roll-off-able steel sheet roof and not secure enough..

[h0ughy]

.........and you think that your building will be secure:screwy: - if they want it they will break in no matter what:scared:. if you spend the extra for a welded single door and a handle lock you can add a hasp and padlock later. the insulation for the shed is a snap - and works out heaps cheaper - do your homework Ian, r3.75 foil bubblewrap from bunnings and some timber for basic framing and a staplegun and tape- the roof is very lightweight with a prefab shed. Mate i am surprised - you are supposed to be an engineer? Typical GB:lol: getting someone to do the concrete - priceless - especially if you have NFI;):thumbsup: you spent nearly a grand with your own quote for just mass concrete no reo, and labour is well worth it in this case. the timber framing screwed to the steel will be pretty solid. they only use a crappy piece of MDF on houses for framing integrity at the front. Save your money and get it done when you have the full amount:whistle:

[Ian Robinson]

Yep , if a villian wants in and really wants what's inside the shed, you can't stop him getting in if he is determined.

I'm not a builder or a carpentor or a metal worker (some welding skills and machining would be very handy) by any stretch of the imagination , never had the need to develop those skills , and am a novice at this DIYS building thing . can't be an expert at everything and this is a pretty project for me.

I've only done small DIYS renovation projects up to now that didn't involve building anything substantial except when I put up a fence by myself . So - I'm on a very steep learning curve with the shed design and construction and want to get value for my money.

Heck we can't all be expert handymen and DIYSers ....:shrug:

Anyway I've pretty much got what I want to do now ironed out , I've designed up and drawn up my wall frames, I've got what I think should work as for track structure , and I now looking at two options for roof
a) a concave circular segment shaped sheet roof and how to make it "structurally sound"
b) a gabel roof .

Once I've sorted my choice of roof profile and construction , it's matter of getting the slab layed with and 2 concrete piers in place , then getting all my materials quotes for the walls and external cladding (which ever looks cheapest and strongest and easiert to put on the walls) , the track structure , the roof structure , and then getting busy and erecting it around the piers.

I've not spent a penny on my shed yet , except the cost of making a few phone calls , f'ashing off a few faxes and a bit of petrol to look at shed displays.

I'll worry about insulating the walls and roof and lining these later.

Wont be running 220VAC to the shed , don't need it , everything in there will be powered by 12VDC .

How goes your project ?
got the slab down yet ?
What size shed did you settle on ?
Flat ? Skillion ? or gable roof ?

[Ian Robinson]

I'll be knicking some of your ideas from your shed ....:thumbsup:

Never too proud to use other peoples' ideas or to pick other peoples' brains.:D

Wont be any AC power in my shed , all will run from 12VDC batteries.

[Alchemy]

youve got a lot of ideas to cover, my opinions on some issues are

1. framed solid roof is HEAVY but desirable as its less prone to wind, structure needs to be solid enough to support it
2. Wall height - high enough to walk into when closed ( just)
3. scope height- this is a balance between protection from wind and horizon level ( if its too low , limited chance for low objects, if high then wind can effect, bassnuts ideas have merit for auto use. i have mine so when at its LOWEST possible, the roof can just close.
4. thermal stability- mine is all timber with exception of roofing iron.
5. 3x3 is adequate for most uses, i get scope plus table in comfortably.
6. SCP is always visible well above wall height.
7. height of floor- to clear obstacles next door why not lift it and have a chipboard floor- just paint it to stop it from rotting.

http://stormfrontobservatory.googlepages.c om/observatoryconstruction this is how i did mine, might give you an idea or two .... maybee not


good luck with your project

cheers clive.

[Ian Robinson]

Do you mean something like Spacemaker1000 (insulated roofing sheets) ?




in the case of a timber off the ground deck/platform for a floor Wouldn't structural plywood be better ?


Best orientation for roof roller wheels for good load bearing and guiding ?

[Ian Robinson]

Second quote for the same sized slab was a shocker ....

got
slab quote 1) = $1200
slab quote 2) = $2000 , same size slab as above , just moved nearer my northern boundary , pretty hard to see how such a difference can be justified (think he wants me to pay for his Xmas Holiday !!!).

An off ground timber platform is looking more attactive.

[Ian Robinson]

Steel or wooden (pine) frames and trusses ? which would you choose and why ?

[rmcpb]

Why not a raised chipboard floor with a peir coming up through it. Lots cheaper, will never get flooded and its easy to do yourself.

[Ian Robinson]

Looking at that option , for an off ground floor I like structural plywood as the floor material.

[norm]

Hi Ian,

I'm currently building a garden shed 3 x 2.4m using the following:

150X50x2400 H4 treated pine @$10.41 each
150x50x3000 H4 @$15.12

I'm going to use 4 or 5 150X50X2400 for the joists so all up for that is around: $103.11

I had some round logs 90mm with I'm using for posts. However 90x90mm H4 3m posts, will probably set you back $30 - not sure exactly.

Chipboard (yellow tongue)3600 x 900 x 15mm = $36. I was going down the plywood path @$55 per sheet, but saved a few bucks with the YT. One side appears to be painted with clear stuff, the otherside raw chipboard. Even though my flooring will be off the ground by about 250mm, I'm planning of just putting a coat of bondcrete to seal it.

I cheated and used rapid set @ $5.60 per bag.

I guess all up its about $300 much cheaper than a concrete slab, its relatively easy to do.

PS: at the time of writing this, I've got 5 stitches on my left thumb after an accident with my drop saw :shrug::screwy::mad2::doh:. As such, I'm going to now have to supervise the other 1/2 on how to continue construction :lol:.

so if you go done this path - be careful with powertools, especially the ones with blades or teeth!

When complete I;m cladding it with colorbond corrugated iron. 762mm width at anywhere between $12-15 l/m - acutal width is 820-850mm (Lysaght, Stratco etc).

Cheers, Norm

[Ian Robinson]

Similar prices to that I've got from Belmont Bunnings.

I don't own a drop saw .... but do have a circular saw and a jig saw.

[Alchemy]

Quote:
1. framed solid roof is HEAVY but desirable as its less prone to wind, structure needs to be solid enough to support it
Do you mean something like Spacemaker1000 (insulated roofing sheets) ?

i used stanard corrugated color bond with a thermal insulation under it ( the blue/silver stuff that will stop drips.) lots of timber trussess low profile.


Quote:
7. height of floor- to clear obstacles next door why not lift it and have a chipboard floor- just paint it to stop it from rotting.
in the case of a timber off the ground deck/platform for a floor Wouldn't structural plywood be better ?

you could use the heavy duty form ply , id still paint it. i used yellow tounge chipboard, it has an allowance for minor dampness, i painted mine straight away , as its not open unless weather is clear it won't get soaked in a downpour, just a bit of dew. been good so far.



Best orientation for roof roller wheels for good load bearing and guiding ?

not sure what you mean? mine run East /West as per pictures on site listed
http://stormfrontobservatory.googlepages.c om/observatoryconstruction

[I.C.D]

Dave,
Have you got any close up pic or plans on how the roof is built and the roll off section

Ian C

[AndrewJ]

Gday Ian

A mate just finished doing a very nice roll off recently
http://www.billd.net/index.php?option=com_content&view=category&layout=blog&id=40&Itemid=62

After a lot of ideas, he ended up using roller door guides and rollers as per another mate, to move a full gabled roof.
The track/wheels were a bit more exe than cheap wheels from bunnings
but it has positive locking, allows for a bit of play, is self aligning, very easy to weather seal and very easy to move.
Also has a very low profile

Just another option to confuse you with.

Andrew

[Terry B]

I put my own slab in and I'm hardlya tradesman. I bought 100mm x 40mm timber x 4 at 4m as forming timber and 1 sheet of reo mesh to make a 3.5m square slab. This was about $100 delivered 10km out of town.
I nailed the wood to make a 3.5 m box and leveled it wit ha spirit level. It sat on some old bricks that I had at home and filled it in with crusher dust and plastic sheeting (also left over at home). This gave me a 100m thick slab. The contrete cost about $350 delivered. I leveled it with a 4.5m long piece of wood as a screed.
It doesn't have to be perfect as it is just a shed.

[norm]

75mm will suffice for the slab if there is no vehicle traffic:).

[Ian Robinson]

Looking at BillyD's construction . I like the garage roller rail and roller bearings idea a lot.

Unless I hire someone , I'll be working by myself . Any reason stopping the roof from being constructed on top of the rails and rollers and some kind of timber box frame ? (So long as the roof structure can be "locked" in posstion for assembly and cladding , by a couple of strong coach bolts each side say.)

I also noted that he had 5 roof trusses for a 4m long shed , is that overkill , I would have thought not more than 3 trusses would suffice for roof that length ?

The roof sheets will add considerable structural strength when attached as well as the two bracing times which will help stiffen it up along with the timbers the sheets will be screwed to.(I think ... I cheated a bit and looked at how my garage roof is assembled, it stood up the Newcastle Cyclone in June 2007 no problem).

See my proposed roof strut & base layout attached. How's that look ?

[rmcpb]

I suppose you have to remember that the roof will be moveable so it needs to be a bit on the over-engineered side. If the roof was permanently fixed to the walls then three would be enough, just need heavier battens, but as it is going to be under some level of stress when it moves and not really attached a bit of extra weight/strength would be good.

[AndrewJ]

Gday Ian

None at all
He built his roof in situ "whilst thinking how he was going to move it":P,
then, once he decided on the method, and found the bits he wanted,
he just lifted it to sit on the longitudinals holding the rollers.
I dont see why the longitudinals couldnt be fitted first, then correctly packed whilst the roof was made.

Andrew

[Terry B]

We made our roof on the ground without the iron and lifted it up. It probably weighed about 80kg. The iron was put on after it was up there.

[AndrewJ]

Gday Terry

Ian reckons hes doing it by himself, hence building "in situ"
will be the easiest and safest method, if he chooses to go this way.
With the longitudinals carrying the wheels properly chocked,
it will make a very stable base for setting the rafters during assy.

Andrew

[Terry B]

I must admit my brother is a builder and we did it between us.;)

[Ian Robinson]

That's what I was thinking of. (pretty easy to slip some packing in the gap to take the extra load of a fatty like me on the roof while screwing steel sheets in place.:thumbsup:

[Ian Robinson]

That was lucky .... wish I had a builder in the family or my circle of acquaintances , best I can do is my brother in law who used to a carpender but he lives too far away to be much help in this , except maybe if I get stuck and give him call on the dog n bone.

[Ian Robinson]

That is something I am considering as an option too , but it would be a 4 man job lifting a roof of the size I want I think , unless it could be lifted on one end onto the two rails , then slid and lifted from the other end. which would make it a 2 or 3 man job.

The shed bloke said about $180 for his crew to assemble one of their complete sheds pnce a slab had been layed (about 3 or 4 hours he reckoned) , maybe I might assemble the roof on the ground , unclad , and then call that guy and ask him to come and lift and clad it .... that'll save my back .... and would probably be money well spent.

[AndrewJ]

Gday Ian


YOU dont ever get onto the roof, its too dangerous ( for the roof )
You fit the sheets one at a time and screw them down as you go
"standing on a ladder/table inside the shed"
Just roll the roof and fit the sheets as you go
easy peasy, and you do the ridge capping at the same time.
No need to ever get on the roof.

Andrew

[Big Dave]

Look Here 2.8Mb http://www.big-dave.com.au/Plans_Rev1.pdf

As with anything I do, they only make a start and often are varied with material availability.
- Dave

[Terry B]

This is exactly how we did it. Tipped up and 1 set of wheels put on the rail and then lifted by the 2 of us and slid along. See the pic.

[Ian Robinson]

That looks pretty good. I like the way the rollers are enclosed in the channel section.

The welding needed to make the steel frame and to attach the channel rails to the rail supports (all steel is an obstacle for me unless I can get someone to the welding ).

[I.C.D]

Thanks for the info Dave .God this is a great site you ask a question and you get a hole pile of info back Thanks again Clear sky's
Ian C
:thumbsup:

[Lee]

I did the same with mine, my father-in-law and I lifted it up (somehow) and put the iron on the next weekend - I think we both nearly popped hernias doing it.... it was bloody heavy. We over-engineered the roofing section to cope with the strains of rolling back and forth....

link to my info on IIS (http://www.iceinspace.com.au/forum/showthread.php?t=22741)
link to my webpage (http://www.betweentheclouds.com/observatory.html)

good-luck!

[Ian Robinson]

Starting ....

Got a machinist lined up to make an Atlux pier leveling adapter plate to go ontop of my concrete pier , just need to measure it up and give him some drawings .

Will do that tomorrow and hope to have a quote in next few days.

I have a spare CG5 tripod head , I'll use that for the CG5's pier and attach it to a suitable sized steel blank frange, might be some welding needed (6 bits of steel angle). It wont be pretty but I'm pretty sure it'll work a treat.

Once I've have the leveling adapter plates in hand , I'll settle on where to set up the two peirs , dig my two holes and will "pour" them (fine gravel quick set cement with some rebar maybe). After New Year I think.

Then it's either a slab or a off ground deck ???? 5m x 3.2m I think now (to give two piers and two scopes , and one fat astronomer plenty of elbow space). Not decided on that yet.

If I do a timber deck for the ROR shed , I'll do two the same size - we have always wanted a timber deck on the back of the house for entertaining , hanging out and bbqs, two BIYO decks at once at will work out cheaper than doing them at separate times (if I have to hire any tools).

If I go timber deck(s) route - for a deck about 1.7m off the ground what's the best option ?
- Treated pine poles concreted into the ground ? One of my neighbours did a similar deck , still finishing it off , a little worried about giving a easy path for termites to get to into the house if I use timber piers.
or
- piers made from galvanised steel hollow square sections of suitable size - welding needed maybe - bolted to concrete footings in the ground ? (I'll have to dig out my old Steel Designers Handbook to size the steelwork up - very rusty on those calcs).
or
- reinforced concrete support piers (formatube style) with suitable sized in ground concrete footings ?

[PeterM]

Hi Ian,
Just a thought. Don't know if anyone has mentioned these. If you are thinking of not going with the concete slab and want the floor raised then have a look at these ground screws. A friend of mine has just about completed his observatory using these with saddles. Handy if you ever move as the whole lot can come out of the ground.
http://www.krinner.com.au/
PeterM

[Ian Robinson]

Those things look brilliant as a substitute for concrete platform pier footings , my ground is hard as concrete when dry wonder how hard they are to drive into the ground (by hand) ?

Future proofing is also something I am considering - I might get that perfect job and have to move one day (not holding my breath though).

[PeterM]

Hi Ian,
These were used at our Leyburn site, the ground is hard only a few inches down. What we did first was hammer a long steel tent peg (about 10mm thick) into the ground as a guide for the ground screw, poured in a little water. We then bolted a longish piece of 3x4 in between the bracket and with one of us on each end we simply walked around rotating the screw into the ground. They do bite a bit as they get deeper but they are stong as and hold a lot of weight.
PeterM

[el_draco]

You might also look at "Mega Anchors" http://mega-anchor.com/and the "Surefoot" http://www.surefootfootings.com/ system which work on similar principles. I'm about to put up a workshop and house using these and already have the frame from my observatory ready to go on mega anchors. I am also contemplating a "surefoot" as an alternative to burying a cube of concrete.