DIY - TNT Flexi stand in one day!

Hiten

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hmmm....
how about a rubber bush of appropriate thickness without collar and instead of collar nylon washer ???
 

magma

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^^
will work well without collar

actaully that is what ram should try
get a bushing with OD tight fit with glass and ID tight fit with od of rod ( ideallyID threaded- that would be super if possible to procure)
height of bush less that glass thickness

get washer for tightening of appropriate matl not rubber and proper thickness depending on material
i once used 2mm anticarbon
 

trittya

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Hey Magma
Firstly let me comment on the strength/warp factor of plexiglass. I agree that it hardly bends/flexes with a 60 kg load but do consider that your man is not going to stand there for long but your eqpt surely will be there for periods long enough to induce discernible flex. Also, i do not completely agree with venkatcr that a reasonably thick acrylic sheet will snap easily by tightening. For that one has to be very stupid or very strong, maybe both. They use this stuff to make dance floors in nightclubs for people to hop n jump upon.
Magma, I do agree with the factors that you have listed but then being far from any kind of GuruI daresay both my racks were done by a seasoned machinist with minimum machining tolerance gaps. Its not zero but almost as good or else the rods wont enter the holes. Ather reason for sway is the use of spikes as this drastically reduces the surface area of ground contact to a single POINT. Hence SS floorpads become mandatory. Even better if you place the four floorpads on a thick and rigid rug(not the fluffy sort), then mount your rack on that. That way, not only can you pull the rug back n forth easily on a polished/tiled floor (to reach the rear of the rack to change connections) but it protects your precious floor from stains/marks over prolonged periods. With load on your rack, the pads get embedded into the rug creating a slot for themselves forever so make sure you dont try this with the wife's favourite persian carpet. You ll see what I mean when you see the snaps of my friends setup n Guwahati. For my rack, which is about one half bigger, I am using a 3/4" plywood piece as a base(the floorpads are placed on the board) to move the rack for making/ changing connections the rear. More later
 

trittya

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Personally, I feel thick rawhide leather washers work best but i eliminated the use of washers for the shelves in both the racks(except one top shelf in my rack on which currently sits a dell 24" monitor posing as a makeshift TV, thats how i know the flex factor bit as the monitor weighs only about 6 kgs). Wait for me to commence a new thread.
 

Hiten

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Also want to add. Glass hole diameter should not be bigger or glass will be more vulnerable I think....
addition : i.e. if you are adding rubber bush.
 
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magma

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trittaya

i use a variety of things for the floor
check my website
Sound Foundations - Homepage

also understand good machinists may provide proper tolerences, they will never predict rack behaviour
that will come by experience

also a man standing on it provides more or less point load at the centre; equipment feet spread out in four corner reduces flex even more
i have some plexi holding a power amp for just over 2 yrs with no problems
 

Hiten

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I think as I don't like wires jumbling at back I would have shifted single steel rod at the back i.e. two rods at front and at the back single rod. Would make it hollow so wires can be hidden inside. Also if you move one rod at the back glass corners alongside that single rod would be less vulnerable as they would be facing the wall. Would that be good idea ???
 

madbullram

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Hiten: I tried, its very difficult given that the AMP has some 10 input connection from various source, the only option could be for power wires may be.

Even with a wire management snake cover it is difficult.
 

prem

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Hi Trittya


Instead of ss protectors under the spikes use ebony wood. Harmonic development is much better. I prefer Asian ebony to African ebony. African ebony will give you more stage depth but there will be a little suck out in the mid bass.

Metal floor protectors under the spikes will add a resonance. To avoid that use Herbies Fat Dots under the metal floor protectors
 
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Hiten

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MBR yes with so many connection it would be difficult. Hiding power supply cable would be also good, will protect signal wires from interference.
 

reju

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MBR, your DIY session with your wifey is quite amazing. Romantic couple:)
Most us may have to do it alone or with some other help.
Surely your AV experience will be double fun:)
 

venkatcr

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im a bit surprised that you believe that Resonance wise glass is similar to plexii - possibly theoretically this can be proved.Physics and mumbo jubo( i havent actually checked). All i can say is that my clients can hear a good amount of differnce between the two.

What I meant was that Acrylic also resonates as does glass. All material resonate at various frequencies. To reduce Acrylic resonance, you have make it with a polymer or Kevlar or carbon and that will be very very expensive. Even wood resonates, but it is much lower on comparison to glass and acrylic.

Cheers
 

trittya

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Another option is perforations in the shelves, which is not feasible with glass. Also, if one goes in for perforated shelves, one has to increase the thickness as perforations will decrease the structural rigidity of the shelf. The upside is that it increases ventilation from under the component(s).
 

Hiten

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For fun and experimenting resonating frequencies can be measured easily by tuning forks and some mathematical equation OR a high quality mic and a sound editing software. I think measuring with tuning fork for can be fun. :)
 
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venkatcr

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Also, i do not completely agree with venkatcr that a reasonably thick acrylic sheet will snap easily by tightening. For that one has to be very stupid or very strong, maybe both. They use this stuff to make dance floors in nightclubs for people to hop n jump upon.

I think we are talking about different kinds of acrylic. The kind used in dance floors are not the kind you generally get in the market. As I said, it all depends on the polymer and kind of compounds used.

I have seen 10-15 mm acrylic sheets used at home cracking under pressure. I have also seen such acrylics getting tarred with use and loosing their transparency. Many such sheets are popularly used in bathrooms nowadays in place of glass.

Cheers
 

trittya

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You do get them but you have to look hard. I was in Guwahati when I found a shop called Lathe' fibres, selling all kinds of acrylic. I presume Delhi and other metros would be better off but again, I reiterate that nothing beats marine grade ply, (even for speaker cabinets) plus the tooling expertise required for acrylic would push the costs up. Should you still want to go for acrylic, I suggest you try the tinted, scratch resistant variety, its available in dark as well as light tints in grey/brown. Hope this helps
 
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