Do I need sand in my pier?

[Peje]

I just received an Altair 8" pier and I've noticed a few comments regarding putting sand inside the tube to dampen any vibrations. Can anyone shed some info on this? Is it actually necessary? I understand on the face of it that it makes sense but I'd like to know if anyone has noticed an improvement after adding it.

It's a heavy brute, glad I had a helper to assemble

Thanks in advance,

Pete

[Starlight 1]

Well back in the days of hi-fi  I can say 100% the sound was cleaner with sand in the speaker tubes, so its a yes it will help .

[Peje]

Your reply made me scratch my head for a second,...one of those 'what did I just read moments'.

However, I will empty a couple of bags of sand in through the top once it's all mounted and forget about it

[Singlin]

Filled mine up with sand and I feel better for it.

[saac]

Peje sand won't stop the pier from vibrating but it will improve the decay time so worth doing.  I'm a long way off in my astrophotography skill from benefitting from the sand I put in mine but it makes me feel like I know what I'm doing. Kinda like an astrophotography placebo effect

Jim

[Peje]

With mine being zinc'd and powder coated Im not overly worried about rot.

I think Im at the same stage as you, spending money on equipment to compensate for my lack of skill/experience LOL

[Starlight 1]

6 minutes ago, Peje said:

With mine being zinc'd and powder coated Im not overly worried about rot.

I think Im at the same stage as you, spending money on equipment to compensate for my lack of skill/experience LOL

IF you can get the sand in plastic bags or the sand over time will pull the powder coat off , it did with my HI-FI stands in about 5 years .

[Peje]

Hmmn Im less sure about this sand. Might hang back, I can add it at any stage

[trazor]

I would be more concerned over the length of the allthread you have used, and the way the top plate is fitted.

The allthread also looks  tilted, perhaps it's not yet tightened.

 

[Peje]

3 minutes ago, trazor said:

I would be more concerned over the length of the allthread you have used, and the way the top plate is fitted.

The allthread also looks  tilted, perhaps it's not yet tightened.

 

Yeh thats just how it was delivered. Ill be getting the top plate down as tight as physically possible to the lower plate once I have all the other parts, Im a mech engineer so I get how the extra length is far from ideal.

[1parsec]

I don't believe sand will have any positive affect.

When you tap the side of an empty pier you hear it 'ring'.  The ringing is a high frequency vibration with a small amplitude.

The vibrations that astronomers are concerned about are low frequency high amplitude vibrations. 

Adding sand to a pier reduces the audible ringing but wont help with the wobbles we're interested in. 
It may even make things worse because you are adding mass at the top of the pier and this will increase the damping time of any low frequency vibrations.

The pier photo posted by the OP is a good design and a nice 8" section so plenty rigid enough for the length, with the proviso the studding on top needs to be
much shorter so as not to compromise all the good design below. 

If you must put sand in the pier, fill it half way.

 

Edited April 2, 2016 by 1parsec