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DeanoNZL
14-10-2008, 05:36 PM
Evening all.
Firstly, sorry if this is posted in the wrong forum, please move if necessary.

Because I have no building skills,:whistle: I have half paid(a small fortune) to have an outdoor obs with dome built for me.
I have mounted the EQ6 and scopes 1 week after the recommended curing period.
If I tap lightly on the concrete pier, it sends a resonance up to the mount & scopes.:sadeyes:
My question is" Is this normal or acceptable, will it affect performance later?
I would have thought it would be very solid!
Or am I just being too picky?
I need valid advise before I part with the remainder of the money to have bargaining leverage.
Would like to hear from concrete pier owners as to how stable their pier is...
My pier is 2m from ground level to mount(pic attached)

Many thanks

Bassnut
14-10-2008, 07:44 PM
Adrian

You didnt mention what diameter yr pier was, I assume its 300mm or so.

My concrete pier is about that hieght and yes, it pings when belted, but that high frequency is unlikely to cause a problem, Ive never had one. And anyway, yr unlikely to hit the pier whilst imaging !.

Low freq disturbance such as wind will not be a problem (on the pier anyway), I wouldnt worry.

DeanoNZL
14-10-2008, 08:55 PM
Fred,
Thanks for the reply.
It is 300mm.
Puts my mind at rest:D

bluescope
15-10-2008, 08:01 PM
The only comment I would make is .....

What's that plant/tree doing near your observatory ? It may cause probs with your structure ( roots ) or eventually block your view !

Ofcourse it's nothing that a spade or a saw couldn't sort !

Only curious ;) otherwise the obs looks good ! Have fun !

:thumbsup:

DeanoNZL
16-10-2008, 01:56 PM
Steve,
Hadn't even considered that. Thanks for mentioning it.
Whoops, I spilt Roundup on it...:evil:

bluescope
16-10-2008, 04:09 PM
Ahhhhh what shame :whistle:

:thumbsup:

cfranks
17-10-2008, 10:01 PM
A much more stable pier is a steel tube bolted to a concrete base isolated from the obs floor. Fill the tube with dry sand and this will damp most of the vibrations. Not particularly good advise if you have already built the concrete pier but it increased my post count:thumbsup:

When we built the original 20" obs @ Stockport we thought about asking for donations of deceased-members ashes for the damping but never got around to it.;)

Charles