Thanks! I don't know Walton; could you help?
I have four photos of styli and grooves made by Stanton Inc in the fin de siècle 1970s, but they're behind glass with a fancy professional sealed backing. I should bite the bullet, do my duty, dismount and scan them. Maybe interesting, there seems to be a mixup in their titled locations, but I could easily be wrong. Don't know how they were done, but they're labelled up to "2000X" so difficult to have any depth of field optically, and these are all without noticeable bokeh, like your example.
Much thanks,
Chris
I have four photos of styli and grooves made by Stanton Inc in the fin de siècle 1970s, but they're behind glass with a fancy professional sealed backing. I should bite the bullet, do my duty, dismount and scan them. Maybe interesting, there seems to be a mixup in their titled locations, but I could easily be wrong. Don't know how they were done, but they're labelled up to "2000X" so difficult to have any depth of field optically, and these are all without noticeable bokeh, like your example.
Much thanks,
Chris
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Hi Chris,
When you are skating, do you skate on ice ?
No you are skating on water because under pressure the ice gets fluid, the so called plastic phase has been entered.
Right after having moved forward and the pressure has been taken away, the still very cold water returns immediately to its original solid state, without leaving a trace.
When ice is too cold, your weight is too low to get enough pressure to let the solid phase turn into it's plastic state and you can't skate anymore.
This is exactly what happens with vinyl, with the huge pressure/square.
Test are made with LP's made from Stainless Steel, and the result is that the needle pops out of the groove because the steel remains in it's elastic solid phase.
In the attachment this process from solid elastic to plastic phase is not only well described, but also tested in real life on the first pages.
Hans
I should note that Hans and I do not agree with each other on the melting vinyl question. Ice and PVC are very different substances so I cannot see how ice skates have any bearing on vinyl playback. One day we hope to find a concensus but for the mean time we won't fall out over it. Static deformation equations are always used, which is not the case when playing a record.
Hi Bill,
Every substance gets fluid under pressure even gas and steel.
There is no exception for Vinyl.
Diamond on steel has roughly the same low friction coefficient of 0.1 as diamond on vinyl.
But the steel LP will be unplayable.
What explanation can be found for this ?
For me, the ice is too cold to skate
Hans
Every substance gets fluid under pressure even gas and steel.
There is no exception for Vinyl.
Diamond on steel has roughly the same low friction coefficient of 0.1 as diamond on vinyl.
But the steel LP will be unplayable.
What explanation can be found for this ?
For me, the ice is too cold to skate
Hans
The assumption Walton made is that when a solid substance has gone under pressure into the plastic phase and back to its original solid state immediately after pressure relief that this event could be made visible afterwards under an electron microscope.
As far as I know there is no physical evidence for this assumption.
Could be that the molecular binding orientation has changed, but that is not visible in this simple way.
Hans
As far as I know there is no physical evidence for this assumption.
Could be that the molecular binding orientation has changed, but that is not visible in this simple way.
Hans
Walton can be found here:
https://worldradiohistory.com/Wireless_World_Magazine.htm
Download July 1961 pp.353-357
A non-demanding explanation by George Alexandrovich (of Stanton Magnetics and the AES) can be found in Glen Ballou's Handbook for Sound Engineers 1987 pp 888-889 (1st Ed). Here he gives a figure for vinyl melting point of 480F and gives counter-examples of playing metal mothers and wet play of vinyl, including a picture of wet play extreme damage after 100 plays. Metal mothers burn up diamond styli in a few hours and he gives figures of 20,000 to 30,000 psi and 2000F. It's overall a very decent book, covers everything so depth is necessarily limited.
All good fortune,
Chris
https://worldradiohistory.com/Wireless_World_Magazine.htm
Download July 1961 pp.353-357
A non-demanding explanation by George Alexandrovich (of Stanton Magnetics and the AES) can be found in Glen Ballou's Handbook for Sound Engineers 1987 pp 888-889 (1st Ed). Here he gives a figure for vinyl melting point of 480F and gives counter-examples of playing metal mothers and wet play of vinyl, including a picture of wet play extreme damage after 100 plays. Metal mothers burn up diamond styli in a few hours and he gives figures of 20,000 to 30,000 psi and 2000F. It's overall a very decent book, covers everything so depth is necessarily limited.
All good fortune,
Chris
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Maybe, better spun off into a separate thread? Seems a shame to fill this thread with this fascinating discussion.
Sorry for the paywall, it did not show up the first time.
Here another article explaining the same, ei.e. not the melting of ice is the cause of low friction.
No, I do not sink in.
That was the point I tried to make.
Here another article explaining the same, ei.e. not the melting of ice is the cause of low friction.
No, I do not sink in.
That was the point I tried to make.
Thx,
the supposed water under ice skates is replaced here by the presence of a “lubricating ice-rich slurries at discontinuous high-pressure zones (HPZs)”.
I can live with that very complex description of the lubrication layer, although it’s unclear to me where these “ice rich slurries” comes from when formed from solid ice and disappears again into solid ice after pressure relief and how it differs from water.
Anyhow, whatever terminology is used, I called it the plastic phase, but given the fact that the pressure on the vinyl exceeds the point of elasticity, a similar process while playing must be happening or else playing would be hardly possible without damaging the LP and or needle tip.
It would be interesting to prove this by playing an LP at a temp way below room temp just to imitate the impossibility to skate on ice that’s too cold.
Unfortunately I don´t have a freezing cell large enough for that test.
Hans
the supposed water under ice skates is replaced here by the presence of a “lubricating ice-rich slurries at discontinuous high-pressure zones (HPZs)”.
I can live with that very complex description of the lubrication layer, although it’s unclear to me where these “ice rich slurries” comes from when formed from solid ice and disappears again into solid ice after pressure relief and how it differs from water.
Anyhow, whatever terminology is used, I called it the plastic phase, but given the fact that the pressure on the vinyl exceeds the point of elasticity, a similar process while playing must be happening or else playing would be hardly possible without damaging the LP and or needle tip.
It would be interesting to prove this by playing an LP at a temp way below room temp just to imitate the impossibility to skate on ice that’s too cold.
Unfortunately I don´t have a freezing cell large enough for that test.
Hans
Vinyl isn't anywhere near its melting point when the pressure is applied, unlike for ice-skates, and it expands on melting, not shrinks like ice, so a very very different situation, I would expect much heating unless undergoing very heavy plastic deformation such as under a cutting head. And all the friction heat is instantly taken away by the diamond, its a fantastic conductor of heat, far better than copper, and the cantilever probably acts as an air-cooled heatsink for the stylus, given the air dragged round by the spinning disc...
I suspect the carbon-black lubrication and other plasticizers play a large role in the stylus/groove dynamics. Whether PVC is even elastic in this regime is questionable, thermoplastics have a lot of creep and recovery, involving entropy as well as elastic strain. The plasticizers may migrate to the surface and back again under pressure perhaps?
I thought clear vinyl wore a lot faster than the black sort anyway - carbon black contains a lot of buckminster fullerenes, which act as nano-scale ball bearings perhaps, avoiding direct contact between PVC and diamond?
I suspect the carbon-black lubrication and other plasticizers play a large role in the stylus/groove dynamics. Whether PVC is even elastic in this regime is questionable, thermoplastics have a lot of creep and recovery, involving entropy as well as elastic strain. The plasticizers may migrate to the surface and back again under pressure perhaps?
I thought clear vinyl wore a lot faster than the black sort anyway - carbon black contains a lot of buckminster fullerenes, which act as nano-scale ball bearings perhaps, avoiding direct contact between PVC and diamond?
