My recently completed 5.3 metre dome went for a ride on a freak gust of wind yesterday. It soared 30 metres and from the marks on the trees and ground it looks like it flew about 20 m then rolled, tilted and landed flat on our driveway. Totalled - bent, welds broken, sheets mangled, way out of round. Miraculously the scope and all the contents were entirely untouched. The securing of the dome is very strong. It's just that I forgot to do it. There is a lesson here somewhere....... 300kg of wreck sitting 30m from its home. ah well, back to the drawing board.....
Geez...talk about bad luck!!!!. Sorry to see that happen, mate. You'll have to secure the scope and such now, from the weather. Is there anything salvageable out of the dome, at all??
Sorry to hear of your misfortune. It makes you realise just how much power wind can have - 300kg through the air for 20m. Amazing! You'd think that weight wouldn't need much securing....
Geez...talk about bad luck!!!!. Sorry to see that happen, mate. You'll have to secure the scope and such now, from the weather. Is there anything salvageable out of the dome, at all??
Hi Carl,
Thanks for the comiserations. Got the scope under a heap of tarps etc. Best I can do for now - and I only drift aligned it to its best ever position last week!!!!
Nothing worth salvaging from the dome. THe base is fine though. I'll start again. I learnt a lot from the first building experience so Dome 2.0 will be a better effort. I am looking at tough "truckies' tarp" - a kind of very tough PVC - type covering which you see on big rigs. Perhaps I will get it made in a hemispheric shape and fit it onto a much lighter but stronger frame.
Richard, why not get just a Observatory Dome like mine.
Considering your telescope fitted fine when i had it, its easier stronger, and can be controlled by computer easier.
??..
I think also, that that 22" could take a massive pounding before it gets any damage !.
OH, I know the feeling, a brilliant dome design in every respect........ except when its windy. Isnt the only problem with yours that it wasnt attached to the walls sufficiently?.
Thanks, lads.
Theo, I'd love a dome like yours - cost is a bit of a hurdle though.
Chris, thanks fo rthe info on Tautliner.
I'm going out tonight to look through the scope. Visually with no camera (!) and very al fresco with no dome. But you can't keep a good (read obsessed) amateur astronomer down for long!
I installed an anti-lift system that is permanently engaged - but allows the dome to rotate freely. In addition, I have three systems to lock the shutter down, and I don't leave the obs without doing a check that all three are done. Something to consider for MkII. I could dig up some pics if needed.
on no sorry for your loss Richard i would have been devastated. Glad the rest of your gear is OK You got a nice big scope there would be sad to see that half way down the driveway
Yes, Jen,is was a surreal moment when my wife rang me at work and said, "Sweetie, the dome is off the base." I thought the breeze had pushed it off its runner - about two inches. Then she gently explained that it was 30 metres off its runner. Say wha???? Then I got home and the thing is perched in the driveway. It was a surreal moment like when a tornado has been through and some things are annihilated and others left pristine. Gladly the scope was OK. Even the ladder I use was still standing even though it was several feet above the base - which shows how high the original lift off was when the gust got under the dome!!!
The sketch shows a cross-section of the dome's running gear. I fixed rolled sections of C-channel to the underside of the dome ring, and then attached 13 brackets (coloured purple in the sketch) such that they sat inside but cleared the C-channel. Therefore the dome can lift only about 6 mm before it's stopped. I'm not aware that it has ever lifted, even during 100 kph wind gusts.
It would have been far simpler to not use the C-channel and make brackets that came over the top of the dome ring, however that design would have been dangerous in terms of getting fingers caught.
When closed, the shutter is clipped at the top, clamped at the bottom, and also roped at the top - just to be sure.