Vibration isolation padding for pier - good idea?

[RugbyRene]

Hi all,

I'm in the process of installing a pier in my garden. I'm putting a concrete plinth onto sandstone.

My question is would it be worth putting a layer of vibration isolation material underneath the pier, so that it sits between the bottom of the pier and the block of concrete. I was thinking this would help absorb extraneous vibrations, passing vehicles being the most obvious.

Rene

[glend]

Unless you live next to the M2 I would not bother. Any sort of vibration damper is going to allow some flex anyway.

[RugbyRene]

That's what I figured but thought I'd ask in case it was the best idea ever! :D

[Andrew_F]

HI Rene,


I'd concur. If it's really necessary later, we used to mount vibration sensitive hardness testing equipment in industry (steel mill) next to a processing line that vibrated the whole floor noticeably, by simply sitting the machine onto a bit of plywood which floated on a 'sheet' of 8 x 6 = 48 tennis balls trapped in an appropriately sized plywood frame.

Worked perfectly and removed 99+% of serious vibration as a simple damper.


This would be a simple addition to the slab later if vibration is an issue.


The issue with the under-concrete mounting is that if there's any dirt, the swelling of wet soil might cause an issue with slab cracking or out-of-level.



(I bought that Meade LX90 off you a while ago, but new streetlight plus neighbours floodlights plus a 40kg pup have completely stopped any observations.)


Regards,

[Startrek]

If your footing is adequate for your pier and your pier diameter is adequate then it’s probably not required unless your imaging at ridiculous focal lengths , +3000mm
My rig in Sydney ( EQ6-R + 6” Newt , soon to be 8” Newt ) is sitting on pavers ( compressed river sand ) near my pool and I’ve done jump tests near the rig whilst guiding and no issues at all with Star shape ( focal length 900mm , soon to be 1050mm )

My NexDome Obs down South has an EQ8-R mount using the monster pier tripod with a 10” f5 Newt ( focal length 1280mm ) , sitting on 3 concrete piers , 300mm dia and 1200mm high ( 750mm in the ground and 450mm above ground. Piers are into a 500 x 500 x 300mm footing ( with 12mm steel reo rods and mesh ) Location site on clay.
Again I performed a knock test with a rubber mallet on the pier base footing whilst imaging , no issue with PHD2 guiding.

I’m sure that really high piers ( 1.5 to 2m + ) or narrow piers 100 to 200mm dia would be more susceptible to vibrations

My 2 cents …..

Martin