Some initial obsy and pier questions

[swag72]

Hubby has suggested that I might like an obsy of some description - Probably a rather small flip top type. Anyway, I'm not sure if where I am thinking of putting it is OK, nor what I am thinking od using for the pier.

So a couple of pics to set the scene. Excuse the pics, they are poor!!

the first two pics show where my tripod is currently located - Left up in all weathers at the moment!

I am aware that surrounded with concrete is not ideal in the hotter weather, but it's just not an option for me. I am wondering whether I can use picture 3) for a pier. We have one for our satelite dish so it would be very stable. But I would not be able to mount it on a great big slab of buried concrete, it would have to be a similar mounting to what you can see here.

The last 2 pictures are where I am comtemplating some kind of obsy build. The size measures 2 x 2 metres. As I said, I would only be able to have a concrete slab for the pier as underneath the flat roof is a kitchen area. It will not be used while I am out so there will be no vibrations. Again, I know there's concrete all around, but what can I do?

So do you have any thoughts on this? Would the pier be OK without the massive buried concrete slab that many have? Am I going to be OK with the amount of concrete around?

I'd like to keep this fairly low in height as it will stick out like a sore thumb if it's normal shed height.

[swag72]

Anyone any thoughts on what I would be using as a pier?

Would the way I would be fixing the pier be usuable?

How about where I am looking at locating the obsy? On top of the roof - Any issues with this?

Would welcome your thoughts on this guys as I don't want to get it all wrong.

[Psychobilly]

is the roof load bearing... would it take the weight of a piece of thick steel plate and additional weights in a small area?

If it is I would be inclined to fix the pier to an oversize plate (12mm thick) and then put additional weight (sand bags or planters) on it as a sustitute for the pier foundation...

You could possibly put some rubberised cork matting under the plate for a bit of vibration isolation...

We used to make rough and ready optical tables using thick steel plate on top of large polystyrene blocks..

last thing you would want is the heavy setup coming through the roof and ending up demolishing the kitchen table and anyone around at the time...

Peter...

[ncjunk]

Well its a Spanish house so I would imagine the roof is solid concrete. I dont think it would be too much of an issue to attach a pier to it if you wanted. Are you getting rid of the satellite dish then? The satellite support does look like it may be modifieable, don't forget your handy local Tornero will be able to knock up a pier or any attachment for you quite quickly...mine did an eq6 attachment for 100 euros.

Are you thinking of a little roll off shed to house it? You could use one of the plastic ones you can get over here and mount it on wheels just to protect everything when not in use.

I've forgottent the original question now...

[ncjunk]

Replace quickly with easily...nothing spanish is quick...took my Tornero 8 weeks to do the pier head for me..

The satellite support looks perfect by the way..

[swag72]

Thanks for the comments - I think that the roof is pretty solid, as everything is concrete out here! I'm not getting rid of the satelite dish, but can easily get another similar pier to that one. It would also involve less fabrication!

Yep Neil, I am thinking of a plastic type shed that I can roll on and off.

Neil, do you have a plan of what you got your local fabrication guys to make? I have one down the road, so that's an idea, but I'd really not know what to ask them to make.

[yesyes]

Well, whatever you do to have a (semi) permanent setup, it will be better than the tripod, even if it won't be as good as an obs with a concrete base pier.

That location on the roof looks very good as you seem to have good all-round views from there.

It's not so much about the vibration from the kitchen below but more about the vibrations caused by you walking around the scope. How heavy is that support under your satellite dish? maybe there is a way to put it on some sort of spikes to reduce the transmission of vibrations from the roof to the mount.

I'm guessing having it suspended on liquid Mercury is out of the question...

[swag72]

Yes, the roof views are good. They are 360 degree, although as I'm on a bit of a hill, I have to wait for stuff to rise a little in the East.

Regarding the vibration with me walking around, I set the camera to a timed delay before it takes starting pics so that allows me time to get away from the setup. Then, I don't tend to go and check again too often!!

I am thinking that I'd like to get hold of some plans of a pier and the HEQ5 mount support so that I can see if the local fabrication shop can make one - Mmmm, off to search the internet!!

[Steep]

If as you say the roof is concrete and you get a similar slab to your existing one, could you not bed the slab down in (half an inch of) concrete/cement so that it almost becomes part of the roof? at least as far as the pier is concerned that would be pretty solid.

[swag72]

I was thinking of a slab of concrete similar to the satelite pier picture. That also had bolts drilled into the floor, so it is pretty stable (needs to be when the wind gets up behind that 1.9m dish!!)

[ARudd]

Vibration Isolation, Vibration Control, Vibration Isolator, Vibration Isolation and Control Systems: Vistek Inc.

[ARudd]

Check out this company, they make customized vibration platforms and tables... this may help you out.

[Psychobilly]

Sufficient Mass and vibration isolation from the roof are how i would go about it ... used to work for our holography setups ... you can buy isolation pads or Sorbothane sheet although rubberdised cork is a cheaper but less effective alternative

Billy on the San Fran

.....

[swag72]

You'd put the anti vibration between my concrete slab and the existing roof?

[Psychobilly]

I would use thick steel plate as the "foundation" and have the AV material between that and the roof... Teh pier could be fixed to the steel plate and if you wanted or needed extra "mass" then you could create a box and fill it withe sand or gravel.. that way it can be removed if you ever need to shift it...

Peter...