You can get square rubber pads with centre depression (just right for tripod feet) from Bunnings for around $5 - you'll want the largest size, which is about 6cm on side.
Or, you can get wooden "cups" with felt pads, again from Bunnings, for around the same cost - I suggest the "tiered" style - you'll know them when you see them.
I prefer the wooden/felt stuff indoors and the rubber pads outdoors on hard surfaces. On grass, I use wooden fence paling off-cuts to provide a stable surface.
In my experience, based on using Celestron’s original Vibration Suppression Pads, VSPs mainly reduced the dampening time rather than eliminate vibrations. I think that they used a sorbothane type material as the main dampening medium.
Correct Dennis, it was to reduce the time of the vibrations, sorbothane does ring a bell too.
My tripod sits seperately to my observatory floor. Essentially, where I walk is floating and the tripod sits on raised concrete on the ground. So my walking isn't a problem, and if I kick the tripod, thats my own fault. However, cars cause a vibration so I should only need to isolate that.
Depending on how much dampening you want, you could modify any or all Bunnings stuff - e.g glue some EVA75 foam, or even a cut-up old neoprene beer cooler, to the bottom of said rubber pad.
I have a dampener platform for my CD player that uses sorbothane feet. It seems to work, or at least I imagine it does.
Here are the results of some practical tests I did several years ago to determine the effectiveness of using a set of Celestron vibration suppression pads (VSP's) to:
better understand how they perform and;
measure their contribution in suppressing vibrations for visual observing.
Approach:
A red LED was observed to oscillate in a Vixen ED 102mm f9 refractor using an illuminated reticule, (6 concentric circles), whilst a tennis ball suspended on a fixed length of string was made to strike the focuser under controlled conditions.
The tennis ball was made to strike the focuser.
The LED was initially displaced to circle 5 in the illuminated reticule.
Two measurements were taken for each strike.
Measurement 1 - the time for the LED image to stabilise within circle 4 was taken.
Measurement 2 - the time for the LED image to become completely stationary was taken.
Conclusion:
The VSP's had no discernible effect on the amplitude of the displacement.
However, the VSP's significantly reduced the dampening times.
See the results and methodology that follow, for details.
Without VSP's:
Measurement 1 - Five separate strikes; LED image stabilized with circle 4, after 3 seconds had elapsed.
Measurement 2 - Five further strikes; LED image came to rest after 6 seconds had elapsed.
With VSP's Fitted:
Measurement 1 - Five separate strikes; LED image decayed to inside circle 4, after less than 1 second had elapsed.
Measurement 2 - Five further strikes; LED image came to rest within 1 second, i.e. the LED returned to its stationery position in one second, without oscillating within circle 4 as previously.
Results:
Based on 20 individual strikes, and within experimental error, the VSP's had no discernible effect on the amplitude of the displacement. However, the VSP's significantly reduced the dampening times. Timing measurements relied on hand/eye co-ordination to start/stop the timer.
Orion Optics (UK) pier with adjustable feet. 1.1m long. Feet are terminated with metal plates that are slightly smaller than the VSP central pad.
OTA/mount configuration:
Dec shaft was horizontal.
OTA was horizontal.
Testing Surface:
Concrete floor.
Light Source:
Red LED approx 25 metres away.
Mechanical Striker:
Lawn tennis ball suspended on a piece of string 30 inches long. The ball was pushed back with my extended arm, to a marker, and then let go to strike the focuser tube with a single hit to produce a reasonably consistent and repeatable striking force.
Timer:
A kitchen LCD timer with press to stop/start button.
Method:
The red LED was acquired in the GA-3 illuminated guider with 10mm Plossl eyepiece. The reticule has 6 concentric circles. The largest circle (6) was visible just inside the edge of the field of view. When the focuser was struck by the tennis ball, the initial LED displacement was out to circle 5.
The first measurement was taken when the LED's amplitude was wholly within circle 4.
The second (stationary) measurement was taken when the LED ceased all movement.
Thanks Dennis, I did read your experiment before posting and it is very well done, and shows that there are certainly improvements to be had.
Whilst the VPS units work, they are so short in life that I have to lift the mount and replace at $80 each time, wasting time with polar alignment all over again.
Also, I am not overly concerned with something physically touching/hitting the mount, mainly vibrations from cars/trucks on the road next to the observatory, (less than 20mtrs away).
I will replace the Meade pads with the Bunnings rubber pads and report back if they have done the trick.
The Celestron ones don't break. it is well known the Meade ones do.
However, replace the center "puck" with a harder material, like aluminum, or a different material (like wood) and they will still perform their function, but without breakage.
They are useful even on stable scopes. A similar test to Dennis' back in the '90s showed my LX200 Classic (alt-az) had a <2 second vibration period without the pads. With the pads, the oscillation was too short to measure.
They are useful on nearly any scope that weighs less than 300 lbs or so, IMO.
Afraid not Don, they still break with a harder central puck. I made some ally ones. It's the continual weight upon them that causes pressure, breaking the outer casing eventually. Mine went another couple of months after early detection of outer casing cracks & I simply attached some strong tape around their circumference.
Ah,
All the ones I'd seen break, it was the central puck that broke.
In that case, you did exactly the right thing.
I've not seen any broken Celestron ones, though they are made of plastic.....
Just my luck to buy the Meade ones They did last for several months but all they had sitting on them was a CF C11 & the EQ6 which I thought was not out of the ordinary (weight) in an average setup these days. Anyway, my low tech approach since then (tyre rubber) is working well enough for now
Oh, & a picture. The one that shattered, I ended up making a new casing & central puck but eventually the other 2 went the same way so I ended up cracking it & binning all 3.
They did last for several months but all they had sitting on them was a CF C11 & the EQ6 which I thought was not out of the ordinary (weight) in an average setup these days. Anyway, my low tech approach since then (tyre rubber) is working well enough for now
