'virgin' vinyl is quite simple: new raw material and not recycled
Advantage: pure material, no unknown residuals
'better' vinyl: maybe different grade or base material - as said, e.g. the ratio of VinylChloride and VinylAcetate can be modified leading to different charcteristics. Maybe 'better' is such a modification with one parameter optimized for whatever reason
Advantage: pure material, no unknown residuals
'better' vinyl: maybe different grade or base material - as said, e.g. the ratio of VinylChloride and VinylAcetate can be modified leading to different charcteristics. Maybe 'better' is such a modification with one parameter optimized for whatever reason
Hans,
I'm not an expert in exactly these materials - I 'only' have good experience and knowledge on plasic materials in general.
Here are some quotes on the Copolymer:
'Polyvinyl chloride acetate (PVCA) is a thermoplastic copolymer of vinyl chloride and vinyl acetate. It is used in the manufacture of electrical insulation, of protective coverings (including garments), and of credit cards and "vinyl" audio recordings'
'Polyvinyl chloride acetate (PVCA) is a transparent, mostly amorphous thermoplastic copolymer of about 80-95% vinyl chloride and 5-20% vinyl acetate'
Finding friction cefficients for this material (and amorphous plasics in general) in combination with other materials (we are interested in diamonds) is quite difficult as they are not usefull for slide bearings or similar applications
I think that the friction coefficient itself will not be very special (unexpectedly low or high). As we pull the diamond tip through the groove with quite a high pressure, I believe that on a microscopic scale there will be a small wave at the rear side of the tip created in the plastic due to its structure (long spaghetti like interwoven polymer chains). Due to the high pressure, the tip sinks in and a small bulge is created when the stylus moves. This is not due to melting! The surface structure will not be destroyed as the material will flow back (with some time delay) and will restore the original shape. If the material temperature rises due to frictional forces, this will help in the relaxation process. If temperature would rise up to the glass transition point of the material, this would result in permanent damage of the fine structures as this would destroy the memory in the material. The deformation creates local stresses in the material (the chain molecules will partly shifted against each other, but not break) wich will relax over time as the molecules will find their inital positions where all build-up forces are minimal again.
Bottom line, wear will mainly come from dust particles, worn diamond tips resulting in chisel like shapes etc. This all will destroy the surface mechanically by cutting molecule chains or by pressing in hard particles.
The image in an earlier post showing a very bad worn groove after wet playing may come from chemical interactions. PVCA needs some additives as the pure material is quite brittle (the material also changed over time: early pressings are often thicker and harder while later pressings became thinner to save money, but the material also got much more flexible)
If the wetting agent disolves some of these additives will making the groove surface brittle (only a few nanometers).
I'm not an expert in exactly these materials - I 'only' have good experience and knowledge on plasic materials in general.
Here are some quotes on the Copolymer:
'Polyvinyl chloride acetate (PVCA) is a thermoplastic copolymer of vinyl chloride and vinyl acetate. It is used in the manufacture of electrical insulation, of protective coverings (including garments), and of credit cards and "vinyl" audio recordings'
'Polyvinyl chloride acetate (PVCA) is a transparent, mostly amorphous thermoplastic copolymer of about 80-95% vinyl chloride and 5-20% vinyl acetate'
Finding friction cefficients for this material (and amorphous plasics in general) in combination with other materials (we are interested in diamonds
) is quite difficult as they are not usefull for slide bearings or similar applicationsI think that the friction coefficient itself will not be very special (unexpectedly low or high). As we pull the diamond tip through the groove with quite a high pressure, I believe that on a microscopic scale there will be a small wave at the rear side of the tip created in the plastic due to its structure (long spaghetti like interwoven polymer chains). Due to the high pressure, the tip sinks in and a small bulge is created when the stylus moves. This is not due to melting! The surface structure will not be destroyed as the material will flow back (with some time delay) and will restore the original shape. If the material temperature rises due to frictional forces, this will help in the relaxation process. If temperature would rise up to the glass transition point of the material, this would result in permanent damage of the fine structures as this would destroy the memory in the material. The deformation creates local stresses in the material (the chain molecules will partly shifted against each other, but not break) wich will relax over time as the molecules will find their inital positions where all build-up forces are minimal again.
Bottom line, wear will mainly come from dust particles, worn diamond tips resulting in chisel like shapes etc. This all will destroy the surface mechanically by cutting molecule chains or by pressing in hard particles.
The image in an earlier post showing a very bad worn groove after wet playing may come from chemical interactions. PVCA needs some additives as the pure material is quite brittle (the material also changed over time: early pressings are often thicker and harder while later pressings became thinner to save money, but the material also got much more flexible)
If the wetting agent disolves some of these additives will making the groove surface brittle (only a few nanometers).
Pure PVC tubes are widely used as infusion tubes! But for these purposes, only very pure raw materials are used with special additives to make them flexibel, which are bio compatible. Standard PVC additives like Phtalates would poison you!
aboos,
Thank you for this most informative explanation. These are the things that interest me. Much the same as other subjects where a person assumes that all things are equal. One of the best examples that I can give is about lubricants. In a word, oil is not just oil. I won't derail the thread with this, as it is incredible all in its own little corner.
The product LAST was mentioned earlier however, and as a user of the product, I still don't understand how it works. Do you have any observations or explanations for it?
Thank you for this most informative explanation. These are the things that interest me. Much the same as other subjects where a person assumes that all things are equal. One of the best examples that I can give is about lubricants. In a word, oil is not just oil. I won't derail the thread with this, as it is incredible all in its own little corner.
The product LAST was mentioned earlier however, and as a user of the product, I still don't understand how it works. Do you have any observations or explanations for it?
aboos,
I had meant to be funny, but your comments do raise yet another interesting question about the time scales associated with vinyl records. At the risk of introducing Lore, which is the usual abode of geezers like me, let me introduce another observation: I've noticed, and over time scales (decades) that cannot possibly be verified, even in my own imagination, that vinyl records seem to restore themselves after many decades. Most probably human fallibility, but I can't tell from inside my own head. It seems to me that records from my teens (late 1960s) like the Toscanini that I played for my 11th grade English teacher and ground to mush now sound much less distorted.
Yeah, FUD lore, but if we weren't vulnerable to it, we wouldn't be in such a dangerous political situation, and not only in America,
Goddess bless us every one,
Chris
I had meant to be funny, but your comments do raise yet another interesting question about the time scales associated with vinyl records. At the risk of introducing Lore, which is the usual abode of geezers like me, let me introduce another observation: I've noticed, and over time scales (decades) that cannot possibly be verified, even in my own imagination, that vinyl records seem to restore themselves after many decades. Most probably human fallibility, but I can't tell from inside my own head. It seems to me that records from my teens (late 1960s) like the Toscanini that I played for my 11th grade English teacher and ground to mush now sound much less distorted.
Yeah, FUD lore, but if we weren't vulnerable to it, we wouldn't be in such a dangerous political situation, and not only in America,
Goddess bless us every one,
Chris
Chris,
I think you and I are about the same age and I share your observation. However, my hearing now is not as sensitive as it was in my teens so I hear less of the distortion harmonics and my playback equipment now is an order of magnitude better than what I had in my teens. Wouldn't be surprised if there is some time related memory bias effect at play here.
Ray K
I think you and I are about the same age and I share your observation. However, my hearing now is not as sensitive as it was in my teens so I hear less of the distortion harmonics and my playback equipment now is an order of magnitude better than what I had in my teens. Wouldn't be surprised if there is some time related memory bias effect at play here.
Ray K
Ixnay,
I have no info on what the ingredients of LAST are. In general, having a lubricant film between groove surface and tip reduces the mechanical grinding significantly - so per se not bad for reduced wear. If they managed to have found an ingredient that does not dissolve any of the additives and even closes the surface pores preventing the additives to migrate to the surface (which is/was a major issue with soft PVC in the early days), that might explain the perceived positive long term effect.
Chris,
if the surface got mechanical damage, I do not think that this can restore itself. More probably, you use a different stylus shape today riding on a different portion of the groove wall where less damage is present
I have no info on what the ingredients of LAST are. In general, having a lubricant film between groove surface and tip reduces the mechanical grinding significantly - so per se not bad for reduced wear. If they managed to have found an ingredient that does not dissolve any of the additives and even closes the surface pores preventing the additives to migrate to the surface (which is/was a major issue with soft PVC in the early days), that might explain the perceived positive long term effect.
Chris,
if the surface got mechanical damage, I do not think that this can restore itself. More probably, you use a different stylus shape today riding on a different portion of the groove wall where less damage is present
@Hans Polak,
I have to scan my archives for Alexandrovich's AES Paper, where he reported the damage after wet plays. As far as I remember he was the only one reporting such damage while the other studies (showing also microscope images of the vinyl for each condition) were stating the opposite.
Regarding the ice skating case, the most recent article seems to be this one:
Lever/Lines; Ice-rich slurries can account for the remarkably low friction of ice skates
https://www.cambridge.org/core/serv...the-remarkably-low-friction-of-ice-skates.pdf
Two earlier articles by Lever/Lines (and other authors as well) discussed the various hypothesizes and conclusions:
Lever et al, 2023; Assessing the Mechanism Thought to Govern Ice and Snow Friction and Their Interplay With Substrate Brittle Behavior
https://www.frontiersin.org/articles/10.3389/fmech.2021.690425/full
Lever et al. 2021; Revisiting mechanics of ice–skate friction: from experiments at a skating rink to a unified hypothesis
https://www.cambridge.org/core/serv...at-a-skating-rink-to-a-unified-hypothesis.pdf
I have to scan my archives for Alexandrovich's AES Paper, where he reported the damage after wet plays. As far as I remember he was the only one reporting such damage while the other studies (showing also microscope images of the vinyl for each condition) were stating the opposite.
Regarding the ice skating case, the most recent article seems to be this one:
Lever/Lines; Ice-rich slurries can account for the remarkably low friction of ice skates
https://www.cambridge.org/core/serv...the-remarkably-low-friction-of-ice-skates.pdf
Two earlier articles by Lever/Lines (and other authors as well) discussed the various hypothesizes and conclusions:
Lever et al, 2023; Assessing the Mechanism Thought to Govern Ice and Snow Friction and Their Interplay With Substrate Brittle Behavior
https://www.frontiersin.org/articles/10.3389/fmech.2021.690425/full
Lever et al. 2021; Revisiting mechanics of ice–skate friction: from experiments at a skating rink to a unified hypothesis
https://www.cambridge.org/core/serv...at-a-skating-rink-to-a-unified-hypothesis.pdf
Thx for your input.Hans,
I'm not an expert in exactly these materials - I 'only' have good experience and knowledge on plasic materials in general.
Here are some quotes on the Copolymer:
'Polyvinyl chloride acetate (PVCA) is a thermoplastic copolymer of vinyl chloride and vinyl acetate. It is used in the manufacture of electrical insulation, of protective coverings (including garments), and of credit cards and "vinyl" audio recordings'
'Polyvinyl chloride acetate (PVCA) is a transparent, mostly amorphous thermoplastic copolymer of about 80-95% vinyl chloride and 5-20% vinyl acetate'
Finding friction cefficients for this material (and amorphous plasics in general) in combination with other materials (we are interested in diamonds
I think that the friction coefficient itself will not be very special (unexpectedly low or high). As we pull the diamond tip through the groove with quite a high pressure, I believe that on a microscopic scale there will be a small wave at the rear side of the tip created in the plastic due to its structure (long spaghetti like interwoven polymer chains). Due to the high pressure, the tip sinks in and a small bulge is created when the stylus moves. This is not due to melting! The surface structure will not be destroyed as the material will flow back (with some time delay) and will restore the original shape. If the material temperature rises due to frictional forces, this will help in the relaxation process. If temperature would rise up to the glass transition point of the material, this would result in permanent damage of the fine structures as this would destroy the memory in the material. The deformation creates local stresses in the material (the chain molecules will partly shifted against each other, but not break) wich will relax over time as the molecules will find their inital positions where all build-up forces are minimal again.
Bottom line, wear will mainly come from dust particles, worn diamond tips resulting in chisel like shapes etc. This all will destroy the surface mechanically by cutting molecule chains or by pressing in hard particles.
The image in an earlier post showing a very bad worn groove after wet playing may come from chemical interactions. PVCA needs some additives as the pure material is quite brittle (the material also changed over time: early pressings are often thicker and harder while later pressings became thinner to save money, but the material also got much more flexible)
If the wetting agent disolves some of these additives will making the groove surface brittle (only a few nanometers).
I suppose you haven’t had the opportunity to look at the Bastiaans AES paper.
You are right that the tip pressure causes a temporary indentation in the vinyl, but depending on the shape of the tip with relation to its contact area, some tips will exeed the yield point and press a small part of the vinyl into the plastic state resulting in permanent deformation, so it really melts.
This is the case with round tips. Line contact tips with their much larger contact area won’t exeed the yield point.
As mentioned earlier in this thread, Bastiaans made a mathematic prediction but also measured the real life indentation for verification. From 2 gram and higher, theory and practice matched completely.
Below 2 grams indentation followed a more relaxed line, but however, he proved that with a 18.6u and 11u tip plastic state causing deformation occurred.
Temp rise because of friction will only be a few degrees at the most, so glass temp will never be met.
Damage by dust particles is the area where Last is active. They seem to have developped a fluid that makes it more difficult for the dust to attach to the groove wall.
Read their email in #76.
If you want to receive the full Bastiaans paper in case you are no AES member, send me a PM with your email address.
Hans
Chris,
Could it be your gear is way more sophisticated as so many years ago
Hans
Hi Jacob,
Thx for your contribution.
The problem however is that the slurrie theory available before the Yield point is reached, only applies to crystalline structures, where vinyl has an amorph structure with possibly only a small amount of crystalline content.
I’m afraid it does probably not apply to vinyl.
Hans
I used LAST for cartridges before. But after several applications, some residuals accumulated on the tip of the cartridges. It degraded the sound. I had to use liquid stylus cleaner to get rid of these residuals. In addition, I couldn't hear any difference anyhow.
Personally, I will NEVER apply anything on the surface of vinyl, especially for some of the valuable ones.
Personally, I will NEVER apply anything on the surface of vinyl, especially for some of the valuable ones.
"I have found that very fine titanium dioxide, when used as a record compound filler, imparts an extremely low surface noise to the finished record and also produces a record with exceptionally longwearing to been made of polymerized vinyl halides, such as vinyl chloride. "
https://patents.google.com/patent/US2217170A/en
"According to Gunnar Heuschkel from R.A.N.D. MUZIK, in the past some colorants such as titanium oxide in white PVC used to significantly increase background noise levels. "
https://www.rpmrecords.dk/blog/sound-quality-and-color-vinyl-records/
https://patents.google.com/patent/US2217170A/en
"According to Gunnar Heuschkel from R.A.N.D. MUZIK, in the past some colorants such as titanium oxide in white PVC used to significantly increase background noise levels. "
https://www.rpmrecords.dk/blog/sound-quality-and-color-vinyl-records/
The mentioned patent is from 1940 !
The then available fidelity standard was definitely way lower than it is today and the quality of plastic resins at that time was orders of magnitudes lower. PVC and its composites became the standard material for records when industry switched from 78 rpm shellac disk to 33.3 rpm LP and 45 rpm formats by the end of the 40s / beginning of the 50s
The then available fidelity standard was definitely way lower than it is today and the quality of plastic resins at that time was orders of magnitudes lower. PVC and its composites became the standard material for records when industry switched from 78 rpm shellac disk to 33.3 rpm LP and 45 rpm formats by the end of the 40s / beginning of the 50s
Plastic deformation is really not melting, trust me! If you bend a piece of wire, plastic rod, whatever, permanently then it has yielded and deformed plastically, but it never melted in your hands! There is no "plastic state" involved, plastic deformation just means it deformed irreversibly without fracturing - nothing more, nothing less - this can happen really fast or so slow that the temperature rise of the material is vanishingly small - plastic deformation happens in solids in their normal state when the forces are high enough and there is a mechanism to allow it (if not, the material behaves elastically until fracturing).
To melt a material all the molecules in it gain enough energy to become free to move on their own thereafter without further mechanical energy input. This is random thermal energy. Its a very simple process conceptually.
For mechanical energy to melt a solid typically a high energy shock-wave is required, such as from an explosion-front or hypersonic impact. Or you can apply sufficient friction to impart enough thermal energy to the bulk material.
Plastic deformation involves mechanisms that mainly act over an layers/areas, i.e. only some of the molecules, typically layers that get to slide over each other, allowing the overall shape to change with only a fraction of the material involved directly - the majority is still in the elastic state.
Take a sheet of plastic and cut it with scissors or a knife - this is plastic deformation - but the cut edges show no evidence of melting.
After plastic deformation the material is still in a state of high internal stress, and when the external force is removed creep can lead to some recovery of the deformation, especially in polymers - melting simply removes mechanical stresses.
Most materials capable of plastic deformation will eventually fail on repeated deformation to show a characteristically grainy rough failure surface, indicative of the network of isolated grains within a network of sliding layers, clearly not indicative of liquid state!
Thanks for the excellent description of the classical explanation. Perhaps we could all agree that the question revolves around whether or not the above condition applies to playing vinyl records. Could the test revolve around how much and how fast stresses are relieved?
All good fortune,
Chris
ps: Makes me think about the development of armor piercing projectiles for penetrating tanks and APCs and such. The modern approach is somewhat counter-intuitive.