The Partington invisible observatory.

[Dave_D]

Ok, not really an obsy issue as:

a. it's only a rented house

b. the local scumbags would probably wreak an obsy or shed just for 'fun'

anyway, this is the area where i set my scope up and as can be seen from the pic, the flagged area is less than idea for stable tracking. the flags are literally just plonked on top of a layer of sand and move slightly when walked on.

looking for advice on the best way to stablise the flags. i'd rather not have to rip them up and concrete the area as i can't really afford it at the moment, but if anyone has any ideas?

[dmahon]

1) Don't stand on the flags that the tripod is standing on.

2) Take up the flags and relay them properly.

3) If you image, buy some long cables so you don't get anywhere near it once set up.

[Moonshane]

I agree that sorting out at least the flags you observe on would be a good idea. you could buy a few bags of ready mix concrete and get them sorted for not a lot of cash. would make general use a lot better too. I bet you could sort the lower front left nine flags for <£20.

[Bizibilder]

Lift the flags, level things as best you can then use some dry mortar (Just sharp sand and cement - no water).  Lay the flags on a bet of this dry mix then resist all temptation to stand on them for a week.  Cover with a tarpaulin or similar to keep the rain off.  The dampness in the ground will soon cause the mix to set solid.

[Gina]

Those flags look like a tripping hazard and I think you would be well advised to fix them.  Good luck

[Dave_D]

what i was thinking was to lift 4 of the flags in a square and digging out a 1 foot hole and filling it with concrete and then laying the flags back on top. as this works out at roughly 0.45m³ how does this amount of concrete compare to an obsy pillar foundation?

[Dave_D]

ok, this is how the mount is usually placed. the ground under the flags is pretty poor to be honest so it's looking like a concrete foundation is a must, how deep would i need to go?

previously, i had no choice but to faff around the scope for alignment and whatnot but now i have plate solving up and running, 

[Gina]

what i was thinking was to lift 4 of the flags in a square and digging out a 1 foot hole and filling it with concrete and then laying the flags back on top. as this works out at roughly 0.45m³ how does this amount of concrete compare to an obsy pillar foundation?

Of the same order.  I would say that was slightly more than my pier base - I think the base part of mine came to about 0.35 cubic metres.  It's solid as a rock - oh, it is a rock

[Dave_D]

Of the same order.  I would say that was slightly more than my pier base - I think the base part of mine came to about 0.35 cubic metres.  It's solid as a rock - oh, it is a rock

ahh that's good news. seems like i was being a bit overgenerous. i can probably afford that amount

[Bizibilder]

i would just go for around 4-6 inches of concrete over the whole area - on some hardcore if you have any.  Then the flags mortered on top.  it will be as solid as you need - just don't jump up and down on it whilst you are imaging.  I have my own portable pier on my patio which is around 2" - 3" of concrete with thin "fake" stone flags - only about 20mm thick - mortered on top and this is fine for Solar photography, which is what I use it for.

[bodtwo]

Would it be best to isolate the concrete?

[ollypenrice]

Those flags look like a tripping hazard and I think you would be well advised to fix them.  Good luck

The Landlord would be advised to fix them... 

Olly

[Gina]

Quite right Olly.

[Dave_D]

The Landlord would be advised to fix them... 

Olly

i wish... took 4 months and a dozen angry phone calls for this housing association to replace a broken fence panel...

on to a more thoroughly annoying situation... after having a close look at the patio and a chat with the gas people who are laying new pipes (and a look at their survey charts of this area), it's come to light that i can't really put down concrete as the main drain for the entire row (6 houses) runs right under my patio    and more annoyingly, right under the flags which provide the best view of the sky.

[StarryEyed]

Follow bizibulders advice it wont effect the drainage and can be broken into for maintenance. Generally speaking unless you jump up and down next to the scope it will be fine.

If you are going to dig it out you might as

[StarryEyed]

Well go the hole hog.

(Silly touch screen)

[StarryEyed]

And put in a pier base.