Shed modification for 16-inch Lightbridge.

[okiscopey (Mike)]

I've owned a 16-inch Lightbridge for ages, but it's had limited use in my ROR observatory due to lack of space and wall height. I'd added some castor wheels to the base, but that didn't help much in the observatory.

What to do? Hours of thinking about possible locations (well, half-an-hour) provided only one solution for protection, ease-of-use and sky view: the back of my concrete-block shed.

Too late to change my mind now ... the hole's already done!

I'd originally imagined having a door leading to a fixed 'catwalk' (dobwalk ... dobway?) but soon realised it'd be simpler for the 2.2m high and 0.9m-wide door to be hinged at the bottom and drop down to form the dobway, thus obviating an unwanted permanent obstruction in the garden.

A couple of screw-in legs (?) at the end of the dobway bearing onto a couple of pavers, or strip of concrete, should keep it level. To get a better view of the southern sky, the dobway will need a portable extension, maybe another 2 metres ... no particular problem methinks.

The ground slopes away a bit from the back of the shed, so the downside is that the eyepiece will sometimes be higher than usual, but I'm prepared to live with that.

[ZeroID (Brent)]

A cunning plan, a plan so cunning you could pin a tail on it and call it a dobwalk.
I think your biggest issue will be to make the dobwalk strong enough to not spring while in use. Why not just pour a small concrete pad there and use an ordinary door ? You could give it a wee bit of extension so it was level and resolve your height problem. I'd just box it, 2.5 meter square maybe, get some hardfill and compact it, then pour a 100mm thick slab with a bit of rebo mesh in it.
Could be a nice spot on an afternoon with a deck chair and few bevvies as well.

[alistairsam]

Exactly my thoughts as well
With the dob on the door, it's bound to bend with your weight as well and you'd be moving around it, loads at different points on the door, differing flex
A hard floor outside and the door as a standard door would be a lot more stable

[okiscopey (Mike)]

Thanks Brent and Alistairsam for your input ... greatly appreciated.

I had of course started out with the concrete pad idea, but given the 'operating area' of the Lightbridge I balked at having a permanent 2.5 or 3m square slab in that bit of the garden. (I'd need maybe 3.5m to get a good southerly view.)

I don't intend to walk on the dobway, that would be crazy, but observe from the grassed area, perhaps with the help of a small step or platform.

I haven't ruled out the addition of some strengthening battens under the 'door' if the weight of the Lightbridge needs it.

Anyway, nothing I'm doing is irreversible, so there could well be a slab there in future!

Thanks again for your comments.