DIY sand filled turntable feet
- Thread starter JimmyNeutron
- Start date
Spalls
Making up for lost time
I love this whole topic and how it has gone.
A few posts back there was mention of using either cork or vermiculite as an alternative to sand (or any other solid, I might add). From my perspective, this would be the way to go in terms of using an isolator that is composed of a bunch 'o small particles (sand, lead shot, etc.). The solid particles have a very high density: typical silica sand has a density of around 150 to 160 pounds/cubic foot. They are solid, and definitely not compliant. Unless they are loosely packed, they will transmit vibration due to point-to-point contact when packed. Using a less dense material that has some actual compliance could make all the difference.
I think this makes sense based on my recent review of the various isolators in the Music Direct catalog. Assuming that any of these things actually work, and I suspect that some do (although I would not know as I have two kids in college and I cannot afford them. The isolators, I mean. The two kids in college are enough, thank you). There is a common thread amongst most of them: whether they are composed of some material with "give" (Sorbothane, etc.) or a mechanical combination of springs and ball bearings, neither of which is a solid of high density. A few are, but they seem to be mostly composed of carbon fiber, and carbon fiber seems to be the panacea for everything that ails society these days so I am conveniently ignoring those.
Hacky Sacks are sounding better all the time
I am satisfied so far with my bags of hydrated bentonite. :yes: They are in my price range. You can pick up a 40 lb. bag of bentonite for about $12 at most well driller or irrigation contractor supply yards.
A few posts back there was mention of using either cork or vermiculite as an alternative to sand (or any other solid, I might add). From my perspective, this would be the way to go in terms of using an isolator that is composed of a bunch 'o small particles (sand, lead shot, etc.). The solid particles have a very high density: typical silica sand has a density of around 150 to 160 pounds/cubic foot. They are solid, and definitely not compliant. Unless they are loosely packed, they will transmit vibration due to point-to-point contact when packed. Using a less dense material that has some actual compliance could make all the difference.
I think this makes sense based on my recent review of the various isolators in the Music Direct catalog. Assuming that any of these things actually work, and I suspect that some do (although I would not know as I have two kids in college and I cannot afford them. The isolators, I mean. The two kids in college are enough, thank you). There is a common thread amongst most of them: whether they are composed of some material with "give" (Sorbothane, etc.) or a mechanical combination of springs and ball bearings, neither of which is a solid of high density. A few are, but they seem to be mostly composed of carbon fiber, and carbon fiber seems to be the panacea for everything that ails society these days so I am conveniently ignoring those.
Hacky Sacks are sounding better all the time
I am satisfied so far with my bags of hydrated bentonite. :yes: They are in my price range. You can pick up a 40 lb. bag of bentonite for about $12 at most well driller or irrigation contractor supply yards.
I was able to get the 5 mm x 12 mm bolts at HD today.
All is well - assembled and on the TT now. Listening to Billie Holiday...
Not sure if this makes a difference or not but the TT sounds nice for sure!
Thanks Jimmy and all the others here for the great suggestion/help!
All is well - assembled and on the TT now. Listening to Billie Holiday...
Not sure if this makes a difference or not but the TT sounds nice for sure!
Thanks Jimmy and all the others here for the great suggestion/help!
Calvink100
Active Member
anotherhobby
Active Member
Any chance there are photos available of the following: Was there a vinyl or plastic washer somewhere?
The Iso-feet, in order, a sorbothane pad, rubber, sorbothane, sand, rubber, and felt pad
The Iso-feet, in order, a sorbothane pad, rubber, sorbothane, sand, rubber, and felt pad
Binkman
Lunatic Member
Many people are not aware that silicon gel is an excellent vibration isolating material. (do I mean using silicon from a tube sandwiched in between isolator pads to make your own? Yes unless you want to pay a pretty penny for same.)
http://www.vibrationmounts.com/Products8.htm
http://www.vibrationmounts.com/Products8.htm
I am thinking my Denon DP47 would benefit from such a mod . . . since the plumbers caps are meant to be leakproof, what about an oil/sand slurry? . . . say SAE-50 . . . the main concern would be leakage I suppose, either from the cane tip/cap joint perimeter or from the bolt hole . . . what say you, better minds? . . .
kach22i
Active Member
Nice Link!:thmbsp:
Great thread! (Yes, I know it's a bit old.) I just made a set of these for my Harman/Kardon T/60 that had no feet. The only modifications I made to the design was the use of T-nuts and rubber washers on top of the cap to hold the bolt in place, and a 1 1/2" fender washer on the inside of the cap to give the bolt something solid to hold onto. I also used some black rubber adhesive from the auto parts store to hold the top and bottom together.
I think I'm going to make another set for a T/20 I have in the basement, I'll take photos if I do.
I think I'm going to make another set for a T/20 I have in the basement, I'll take photos if I do.
Spalls
Making up for lost time
Quite right. You would need to use nitrile in place of rubber in the presence of petroleum products to avoid degradation over the long term. How long that may be...:scratch2:
tlarwa
Vinyl Lover
Great job to the OP on coming up with a good solution for new and improved feet. But if you want to see some serious sand-filled feet, check out this TT stand I built! Sand box on 4" sand-filled PVC pipe legs. About 150#. Now this thing really isolates your table! Couldn't help myself
Again, you came up with a good solution to your problem, and affordable! Good job!
Tom
Again, you came up with a good solution to your problem, and affordable! Good job!
Tom
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restorer-john
Addicted Member
I think the OP's sand filled feet are absolutely awesome. A really good option for those rotted out Pioneer PL-518 feet too.
Well done!
Well done!
Vintage Bert
Opinions my own, except those of the Mothership!
Re: varieties of damping materials and their usage...
I think the difficult but ideal theoretical damping material for the "sand-box" design would be alternating layers of differing media. It is analogous to baltic plywood vs mdf vs "wood" for dampening character.
The different media: sand, lead, cork, glass, fluid, what-have-you, all have characteristic densities and conductivities which will be reflected in frequencies they inhibit/transmit. Mix the layers/broaden the frequency inhibitions but at the same time increase cost and nuisance factor. I imagine if you happen to have a phys. eng. lab you can access you could measure frequencies across your "damper" and find an ideal... but my layman's guess it would likely be diminishing returns over plain, simple sand.
I think the difficult but ideal theoretical damping material for the "sand-box" design would be alternating layers of differing media. It is analogous to baltic plywood vs mdf vs "wood" for dampening character.
The different media: sand, lead, cork, glass, fluid, what-have-you, all have characteristic densities and conductivities which will be reflected in frequencies they inhibit/transmit. Mix the layers/broaden the frequency inhibitions but at the same time increase cost and nuisance factor. I imagine if you happen to have a phys. eng. lab you can access you could measure frequencies across your "damper" and find an ideal... but my layman's guess it would likely be diminishing returns over plain, simple sand.
When I built mine I never did get around to adding sand. Whilst doing some mods to my turntable, I have my "Jimmy Feet" under my receiver. A big 45lb beastie. I think I'll make another set with sand so I can do a quick comparison. If it makes no diff with the receiver, I still have another turntable that could benefit from a good set of feet :thmbsp:
