As it has been discussed the Platter Spindle Interface is a poor finish, as the commonly seen Brass Insert used on a Platter is not present and the Platter can quite easily wobble due to the poor fitting.
The Bearing Spindle is now non metal on metal, as the Spindle is meeting Thermoplastic Bushes and a Plastic/Nylon Thrust Pad.
There might be a eccentric axis interface, where the Nipple High Point on the Thrust Pad interface, is worn of its centre, resulting a slip of the axis, which might be occurring during a rotation and able to create a energy that is detectable as a noise?
Has the condition of the Ball to Thrust Pad been investigated, as there are cases of scribing on the ball being known about at these interfaces.
Not that I am suggesting your interface has such a condition, but I would suggest a scribing on a Balls surface can be a cause of roughness to rotation and a cause for a energy produced that is detectable as a noise, but a Scribing would most likely have to be noticeably present to be the cause of a audible noise when rotating.
The Bearing Spindle is now non metal on metal, as the Spindle is meeting Thermoplastic Bushes and a Plastic/Nylon Thrust Pad.
There might be a eccentric axis interface, where the Nipple High Point on the Thrust Pad interface, is worn of its centre, resulting a slip of the axis, which might be occurring during a rotation and able to create a energy that is detectable as a noise?
Has the condition of the Ball to Thrust Pad been investigated, as there are cases of scribing on the ball being known about at these interfaces.
Not that I am suggesting your interface has such a condition, but I would suggest a scribing on a Balls surface can be a cause of roughness to rotation and a cause for a energy produced that is detectable as a noise, but a Scribing would most likely have to be noticeably present to be the cause of a audible noise when rotating.
1 thing to check on if you are taking up the slop in the bearing with oil is to make sure it doesn't leak out through the thrust pad or through the weak rubber seal. when mine had a scored ball there was no noise present during use.all i can say regarding the benifits of the torlon bearing is,i have an sp10 hear that i dont listen to because in comparison it sound weak and thin compared to the sony.
When the HiFi System is completely set up again in a place where I and IT will make Old Bones.
The intention at the present, is to have a Densified Wood Tri-Deck Plinth Produced, which will be much easier to use for the intended purpose, than my original multi deck design, which was based around producing a Plinth, made as a design, that could have a TT mounted on its own Densified Wood Board, which would be inserted into the main structural element of the Plinth, used for structure to mount Tonearms.
I have discovered a new material that I intend on investigating, it is now a material that has found a use as a structural component in Formula 1 design.
This materials is looking to be very interesting, I can see it becoming very popular, as it is of a origin that is relevant to modern thinking on the Philosophy of Circularity. Additionally it is lightweight (very attractive for shipping and ethically cutting back on energy usage for transportation, not like a Densified Wood, the new discovered material also has attractive intrinsic properties that are aligned to what a audio product benefits from as a interface material, maybe even a structural element of a product as well.
Plenty to be learned and hopefully the man who has over the years provided all the data supplied for Densified Wood Types, will discover following my supplying samples, that there is a "new kid on the block."
The Tri-Deck design has simplified the requirement to carry out comparisons and will be great for social get togethers and demonstrations to inquisitive types, who want to learn about Bearing Modification, Vintage DD Sound Signatures, Tonearm Influences on a Cart'.
The Tri-Deck design will possibly not be a Densified Wood design, which will be a decision made depending on the value of the ongoing investigation into the alternative material. D'fied Wood could be superseded or used a Hybrid Material to create the Structure?
The intention in to have another version of the SP10 MKII Bearing Assembly, that is different to the modified one I have already had supplied.
A SP10 MK II Kaneta Design is already owned and this will also have a Bearing Modification carried out to the standard of the one of the two types that proves most attractive to myself.
The TTS 8000 as a standard and well used original bearing, along with the Purpose Produced Bearing using Torlon, Redesigned Trust Interface, and Platter Tightly Fitted to Spindle will also be mounted along side the SP10 MKII designs.
A third DD TT of a Japanese Vintage, will also be included in the Trials, of which I own duplicates of a few brands, and after investigating them, am quite happy to have parts produced to change out the original sacrificial part used at the Bearing Interfaces, to be used as a Comparison to the non-modified same model TT and the other Brands of TT.
I no longer seem to have a interest in a voicing of a Part that is critical to the replaying of a Vinyl LP, most TT's encountered for 40 years or more do that very well.
Where I have developed an interest is in the sound that is being produced, has been able to create the perception that the sound is improved in purity, there is seemingly less contamination being transferred to the styli, hence lesser corruption of the energy transferral that is to become the Source of the Signal to be sent for Amplification.
My learning about this commenced in the 90's when I had my Garrard 401 Bearing completely overhauled by Martin Bastin, and the experience of the returned bearing blew me away.
I have sailed close to the wind on this subject and met with others who share a similar interest, of which some are actively working with machining of materials to create improved interfaces between sacrificial and non sacrificial parts.
I know today, a TT that has a Bearing Assembly that has a purpose produced tight tolerance between the static parts and moving parts interface, will have a axis of rotation that is much improved in accuracy to a Interface with Slop detectable.
A True Axis Rotation from my experiences is a detectable condition, as the reduction in perceived colouration can be discernable in relation to the sound that is being heard.
A much improved Axis Rotation, is not an avoidance measure in place, being a design that will not allow for one to experience Boundary Effect. A TT's Bearing Function does not create the condition that substantially reduces the risk of B'dary Effect occurring.
Most who experience Boundary Effect.
A typical TT will have a eccentric rotation, and the conditions in the Bearing Housing will always remain as a Start Up / Shut Down condition, where a Oil Wedge is not present between Non Sacrificial Moving Parts and Sacrificial Non-Moving Parts.
No Oil Wedge is creating one condition which is Boundary Effect (Metal on Metal Contact).
Eccentric Rotation and Metal on Metal Contact are both producers of energy to be transferred, of which a proportion will transfer to the Styli.
Additionally, Metal on Metal will cause a noise, most Sintered Bushes with 40 years of service being used as Non Moving Sacrificial Part, are no longer working as their new condition, resulting in a soft dry metal being encountered, this type of sintered bronze bush is exposed to the risk of being eroded, and as a result loose particulate will manifest, working as a abrasive.
There will in certain cases of conditions created through dry contact be noise produced that is audible.
The above conditions are ones that can quite easily influence Jitter in conjunction with other influences that are a cause as well.
Avoidance of Boundary Effect is not possible with a typical Journal Bearing Design, the design is a creator of the condition. Hydrodynamic Lubrication is available on a certain type of Bearing Operation, but is not available on the function of a TT's Bearing.
Hydrostatic Lubrication will be much more successful in overcoming the Boundary Effect that is present in a Hydrodynamic Lubrication design.
Avoidance on Metal on Metal contact and excessive eccentric rotation is able to to be completely removed within a Journal Bearing, one method is the Sub Topic of this Thread.
A undamaged clean faced Spindle that has a Metal on Thermoplastic with Impregnated Lubricant contact as a result of Boundary Effect will be a different interface to a dry metal on metal interface.
A Thermoplastic with Impregnated Lubricant, is designed to function in a shaft that is dry.
The noise such a contact is having is very different to other noise having been produced from former interfaces and is detectable and discernable for the perceived improvement that is discovered.
I do believe the improvements detected are with a large proportion attributed to a improved control over Jitter being generated, as well as, enabling the Styli to have encountered the LP's Groove Modulation in a much more stable environment.
It has taken many years of discussion and experiencing the works of others on my owned equipment and that owned by others to arrive at the above descriptions, I am happy to receive further convincing education on the subject.
Jamie,
I recall my first broaching on the subject on AOS, where the concept of this topic was all new to you.
I would not be so sure that the Scribed Ball on the Bearing you are referring to, was not an audible condition, in the same way it was not known the excessive eccentric rotation of the Spindle on the same TT was the cause of a very noticeable Speed Fluctuation when measured with a Standalone Strobe.
Was it not this condition that was the prompt for you to make a request to myself via the Engineer we both know and were very very trusting in, to carry out the work, for your TS 8000 to be worked on before my own.
I recollect my reply being something very similar to:
"I am not without a means to replay Vinyl and I also have plenty of CD's to enjoy. Let Jamies TT be the one that is worked on first."
I later learnt that it was my TTS 8000 that was the one used to take the dimensions and produce the Torlon Parts you had produced for you and my TT's Sump that was used to produce the upgraded Sump Plug that you had [produced for you as well.
It was also my TTS 8000 that was the model used to produce the Group Buy Torlon Bushes as a Well.
Which is now described as potentially not the best method.
It seems that the individual Spindle and Bearing Housing would be needing to be dimension checked to determine the best machining dimension, there does not seem to be a ubiquitous dimension that will work.
I have a Bearing assembly that has zero detection of movement and is a pleasure to feel rotating in comparison to the previous and aged design when operated whilst held in the hand .
Since this experience of being supplied machined parts, you appeared to have taken up engineering as a hobby and have been showing your machining work on a few forums where a selection of the works being shown are your versions of copying the work in various ways that have been encountered by you, prior to your own efforts to reproduce them, of which some are the designs and work already undertaken by the engineer we both have trusted in.
I am very very familiar with your attempts to copy designs, but mostly through the work undertaken by another and their time spent with me describing their design intent.
My wife knows my intentions for the Space I have set aside in the new home plan for the Audio System.
Wonderful Wifey with such knowledge has suggested I build a purpose produced room for the Audio System in the Garden, to be used as a Home Entertainment Space 😎😎. She is happy to have a very concealed Digital Orientated Music System in the new space, with a thought included for Bluetooth Speakers placed around the home.
I'm not sure should I disagree 🤣.
In a very recent post, I referred to the method now being made known to successfully retain Lubricant in the Sump without a leach occurring, I also showed in diagram in a earlier post that a Top Bush can be seated a little deeper, and a felt ring washer can be inserted to absorb a lubricant if a topped up lubricant fill is the wanted method.
This Topped Up fill as a methodology makes sense to keep Lubricant where it serves to be most valuable.
The idea of a Hydrodynamic Condition being created in a TT's Journal Bearing Assembly is one I believe is a fantastical statement being touted by suppliers of a Commercially Produced replacement bearing assembly, especially as most Commercially available designs being seen are simply a plagiarised version of those where the designs origins can be seen on the likes of the forum Lenco Heaven.
On Lenco Heaven there are experienced engineers who are expressing their being advocates of creating a Bearing Housing Base that does not leach lubricant, and encourage a increased fill of lubricant in the Shaft, I would suggest these guy's know there stuff and are worthy of reciprocating there ideas.
The intention at the present, is to have a Densified Wood Tri-Deck Plinth Produced, which will be much easier to use for the intended purpose, than my original multi deck design, which was based around producing a Plinth, made as a design, that could have a TT mounted on its own Densified Wood Board, which would be inserted into the main structural element of the Plinth, used for structure to mount Tonearms.
I have discovered a new material that I intend on investigating, it is now a material that has found a use as a structural component in Formula 1 design.
This materials is looking to be very interesting, I can see it becoming very popular, as it is of a origin that is relevant to modern thinking on the Philosophy of Circularity. Additionally it is lightweight (very attractive for shipping and ethically cutting back on energy usage for transportation, not like a Densified Wood, the new discovered material also has attractive intrinsic properties that are aligned to what a audio product benefits from as a interface material, maybe even a structural element of a product as well.
Plenty to be learned and hopefully the man who has over the years provided all the data supplied for Densified Wood Types, will discover following my supplying samples, that there is a "new kid on the block."
The Tri-Deck design has simplified the requirement to carry out comparisons and will be great for social get togethers and demonstrations to inquisitive types, who want to learn about Bearing Modification, Vintage DD Sound Signatures, Tonearm Influences on a Cart'.
The Tri-Deck design will possibly not be a Densified Wood design, which will be a decision made depending on the value of the ongoing investigation into the alternative material. D'fied Wood could be superseded or used a Hybrid Material to create the Structure?
The intention in to have another version of the SP10 MKII Bearing Assembly, that is different to the modified one I have already had supplied.
A SP10 MK II Kaneta Design is already owned and this will also have a Bearing Modification carried out to the standard of the one of the two types that proves most attractive to myself.
The TTS 8000 as a standard and well used original bearing, along with the Purpose Produced Bearing using Torlon, Redesigned Trust Interface, and Platter Tightly Fitted to Spindle will also be mounted along side the SP10 MKII designs.
A third DD TT of a Japanese Vintage, will also be included in the Trials, of which I own duplicates of a few brands, and after investigating them, am quite happy to have parts produced to change out the original sacrificial part used at the Bearing Interfaces, to be used as a Comparison to the non-modified same model TT and the other Brands of TT.
I no longer seem to have a interest in a voicing of a Part that is critical to the replaying of a Vinyl LP, most TT's encountered for 40 years or more do that very well.
Where I have developed an interest is in the sound that is being produced, has been able to create the perception that the sound is improved in purity, there is seemingly less contamination being transferred to the styli, hence lesser corruption of the energy transferral that is to become the Source of the Signal to be sent for Amplification.
My learning about this commenced in the 90's when I had my Garrard 401 Bearing completely overhauled by Martin Bastin, and the experience of the returned bearing blew me away.
I have sailed close to the wind on this subject and met with others who share a similar interest, of which some are actively working with machining of materials to create improved interfaces between sacrificial and non sacrificial parts.
I know today, a TT that has a Bearing Assembly that has a purpose produced tight tolerance between the static parts and moving parts interface, will have a axis of rotation that is much improved in accuracy to a Interface with Slop detectable.
A True Axis Rotation from my experiences is a detectable condition, as the reduction in perceived colouration can be discernable in relation to the sound that is being heard.
A much improved Axis Rotation, is not an avoidance measure in place, being a design that will not allow for one to experience Boundary Effect. A TT's Bearing Function does not create the condition that substantially reduces the risk of B'dary Effect occurring.
Most who experience Boundary Effect.
A typical TT will have a eccentric rotation, and the conditions in the Bearing Housing will always remain as a Start Up / Shut Down condition, where a Oil Wedge is not present between Non Sacrificial Moving Parts and Sacrificial Non-Moving Parts.
No Oil Wedge is creating one condition which is Boundary Effect (Metal on Metal Contact).
Eccentric Rotation and Metal on Metal Contact are both producers of energy to be transferred, of which a proportion will transfer to the Styli.
Additionally, Metal on Metal will cause a noise, most Sintered Bushes with 40 years of service being used as Non Moving Sacrificial Part, are no longer working as their new condition, resulting in a soft dry metal being encountered, this type of sintered bronze bush is exposed to the risk of being eroded, and as a result loose particulate will manifest, working as a abrasive.
There will in certain cases of conditions created through dry contact be noise produced that is audible.
The above conditions are ones that can quite easily influence Jitter in conjunction with other influences that are a cause as well.
Avoidance of Boundary Effect is not possible with a typical Journal Bearing Design, the design is a creator of the condition. Hydrodynamic Lubrication is available on a certain type of Bearing Operation, but is not available on the function of a TT's Bearing.
Hydrostatic Lubrication will be much more successful in overcoming the Boundary Effect that is present in a Hydrodynamic Lubrication design.
Avoidance on Metal on Metal contact and excessive eccentric rotation is able to to be completely removed within a Journal Bearing, one method is the Sub Topic of this Thread.
A undamaged clean faced Spindle that has a Metal on Thermoplastic with Impregnated Lubricant contact as a result of Boundary Effect will be a different interface to a dry metal on metal interface.
A Thermoplastic with Impregnated Lubricant, is designed to function in a shaft that is dry.
The noise such a contact is having is very different to other noise having been produced from former interfaces and is detectable and discernable for the perceived improvement that is discovered.
I do believe the improvements detected are with a large proportion attributed to a improved control over Jitter being generated, as well as, enabling the Styli to have encountered the LP's Groove Modulation in a much more stable environment.
It has taken many years of discussion and experiencing the works of others on my owned equipment and that owned by others to arrive at the above descriptions, I am happy to receive further convincing education on the subject.
Jamie,
I recall my first broaching on the subject on AOS, where the concept of this topic was all new to you.
I would not be so sure that the Scribed Ball on the Bearing you are referring to, was not an audible condition, in the same way it was not known the excessive eccentric rotation of the Spindle on the same TT was the cause of a very noticeable Speed Fluctuation when measured with a Standalone Strobe.
Was it not this condition that was the prompt for you to make a request to myself via the Engineer we both know and were very very trusting in, to carry out the work, for your TS 8000 to be worked on before my own.
I recollect my reply being something very similar to:
"I am not without a means to replay Vinyl and I also have plenty of CD's to enjoy. Let Jamies TT be the one that is worked on first."
I later learnt that it was my TTS 8000 that was the one used to take the dimensions and produce the Torlon Parts you had produced for you and my TT's Sump that was used to produce the upgraded Sump Plug that you had [produced for you as well.
It was also my TTS 8000 that was the model used to produce the Group Buy Torlon Bushes as a Well.
Which is now described as potentially not the best method.
It seems that the individual Spindle and Bearing Housing would be needing to be dimension checked to determine the best machining dimension, there does not seem to be a ubiquitous dimension that will work.
I have a Bearing assembly that has zero detection of movement and is a pleasure to feel rotating in comparison to the previous and aged design when operated whilst held in the hand .
Since this experience of being supplied machined parts, you appeared to have taken up engineering as a hobby and have been showing your machining work on a few forums where a selection of the works being shown are your versions of copying the work in various ways that have been encountered by you, prior to your own efforts to reproduce them, of which some are the designs and work already undertaken by the engineer we both have trusted in.
I am very very familiar with your attempts to copy designs, but mostly through the work undertaken by another and their time spent with me describing their design intent.
My wife knows my intentions for the Space I have set aside in the new home plan for the Audio System.
Wonderful Wifey with such knowledge has suggested I build a purpose produced room for the Audio System in the Garden, to be used as a Home Entertainment Space 😎😎. She is happy to have a very concealed Digital Orientated Music System in the new space, with a thought included for Bluetooth Speakers placed around the home.
I'm not sure should I disagree 🤣.
In a very recent post, I referred to the method now being made known to successfully retain Lubricant in the Sump without a leach occurring, I also showed in diagram in a earlier post that a Top Bush can be seated a little deeper, and a felt ring washer can be inserted to absorb a lubricant if a topped up lubricant fill is the wanted method.
This Topped Up fill as a methodology makes sense to keep Lubricant where it serves to be most valuable.
The idea of a Hydrodynamic Condition being created in a TT's Journal Bearing Assembly is one I believe is a fantastical statement being touted by suppliers of a Commercially Produced replacement bearing assembly, especially as most Commercially available designs being seen are simply a plagiarised version of those where the designs origins can be seen on the likes of the forum Lenco Heaven.
On Lenco Heaven there are experienced engineers who are expressing their being advocates of creating a Bearing Housing Base that does not leach lubricant, and encourage a increased fill of lubricant in the Shaft, I would suggest these guy's know there stuff and are worthy of reciprocating there ideas.
There used to be a very good web calculator for design of hydrodynamic journal bearings. It was developed by one of the larger engineering universities in the UK.
I can assure you that (if the app was correct) it is indeed possible to have stable hydrodynamic lubrication of a 12mm spindle running at 33.3rpm.
The app gave a variety of outputs including friction torque, bearing stiffness and eccentricity under a given load.
Unfotunately the page has disappeared but there are others available.
Very enlightening. Particularly the effect of viscosity and radial clearance on bearing stiffness - not necessarily what you might expect...
Cheers, and keep up the good work,
Mike
I can assure you that (if the app was correct) it is indeed possible to have stable hydrodynamic lubrication of a 12mm spindle running at 33.3rpm.
The app gave a variety of outputs including friction torque, bearing stiffness and eccentricity under a given load.
Unfotunately the page has disappeared but there are others available.
Very enlightening. Particularly the effect of viscosity and radial clearance on bearing stiffness - not necessarily what you might expect...
Cheers, and keep up the good work,
Mike
@mikey_audiogeek The information that you have referred to would be an interest to anybody working to improve a Bearing Housings Sacrificial Part /Permanent Part Interface.
The science required to achieve this condition is quite special, very much dependent on Machining Tolerance and Lubrication Viscosity. Hence Hydrostatic is the easy fix, but this is not really suitable for a TT as noise mechanical energy will be generated and transferred as a result.
The science required to achieve this condition is quite special, very much dependent on Machining Tolerance and Lubrication Viscosity. Hence Hydrostatic is the easy fix, but this is not really suitable for a TT as noise mechanical energy will be generated and transferred as a result.
Hi Johnny, it looks like I may have misunderstood your earlier post.
The journal bearing calculator helps design the lateral or spindle bearing.
I agree that it doesn’t help with the thrust bearing design.
I also agree that a hydrostatic bearing is impractical in a turntable.
Cheers and thanks,
Mike
The journal bearing calculator helps design the lateral or spindle bearing.
I agree that it doesn’t help with the thrust bearing design.
I also agree that a hydrostatic bearing is impractical in a turntable.
Cheers and thanks,
Mike
@mikey_audiogeek I do believe the Sintered Bronze Bush - 'Oilite' has been selected as the easy fix, but these are only a partial fix.
For the 'Oilite' to perform as per its original intended use the Lubricant that is high pressure embedded, usually about 25% of the overall volume of the 'Oilite' is only activated by a the operational environment having a High Heat.
Even the most modern 'Oilite' Designs or a equivalent can be seen as a low heat design, but this low heat in not as created within a TT's Journal Bearing.
A Sintered Bronze Bush as Interface with the Harder Metal Spindle, as a Metal on Metal contact, will eventually produce the dust / version of dust that the Sintered Bronze Bush is produced from.
This dust will seal the Sintered Bronze Bushes pores, further rendering the already inadequate lubricant, unable to leach out.
Produced Metal Particulate/Dust and the Excess of it, is also an abrasive and will impact on the non sacrificial parts, to the point that a detrimental condition is observable on inspection.
Produced Metal Particulate/Dust and the Excess of it, will fall to the sump, where if can become a abrasive interface at the Thrust Assembly, which can be a cause of Scoring to the surface of the Ball and Thrust Pad.
Abrasive will cause noise and energy transferral.
Any TT of any age, with a Bearing Interface design using parts where metal on metal is able to occur is already exposed to the above condition where the softer Metals Particulate is being produced, and leading to the time a Harder Metals Particulate is being produced of which both are abrasives causing over time detrimental conditions.
Is a Vintage TT with 2000 Hours Playtime and Different to a 5 Year Old TT, with 2000 hours+ Playtime ?
It is generally assumed because of longevity, Vintage TT's are a TT with many more rotations than a lesser aged TT, but this will not be accurate as a assumption.
I have seen TT's with a production from the 00's, with a scored ball at a Thrust Interface, as well as a abraded surface on the a Spindle Wall.
Journal Bearing are very cheap to produce, so why add cost to your product if the customer is accepting of the typically poor quality designs selected for the Journal Bearing.
Thermoplastics are much more suitable as a Bush Interface, as heat is not required to release the embedded low coefficient of friction elements and Metal on Metal is no longer a occurrence.
Adding Oil as a Shaft Fill is a simplistic way of controlling Boundary effect during the rotations, in a shaft with a interface, that has wear developed, but not yet detrimental, the Oil will offer a solution to improving eccentricity during a rotation.
For the 'Oilite' to perform as per its original intended use the Lubricant that is high pressure embedded, usually about 25% of the overall volume of the 'Oilite' is only activated by a the operational environment having a High Heat.
Even the most modern 'Oilite' Designs or a equivalent can be seen as a low heat design, but this low heat in not as created within a TT's Journal Bearing.
A Sintered Bronze Bush as Interface with the Harder Metal Spindle, as a Metal on Metal contact, will eventually produce the dust / version of dust that the Sintered Bronze Bush is produced from.
This dust will seal the Sintered Bronze Bushes pores, further rendering the already inadequate lubricant, unable to leach out.
Produced Metal Particulate/Dust and the Excess of it, is also an abrasive and will impact on the non sacrificial parts, to the point that a detrimental condition is observable on inspection.
Produced Metal Particulate/Dust and the Excess of it, will fall to the sump, where if can become a abrasive interface at the Thrust Assembly, which can be a cause of Scoring to the surface of the Ball and Thrust Pad.
Abrasive will cause noise and energy transferral.
Any TT of any age, with a Bearing Interface design using parts where metal on metal is able to occur is already exposed to the above condition where the softer Metals Particulate is being produced, and leading to the time a Harder Metals Particulate is being produced of which both are abrasives causing over time detrimental conditions.
Is a Vintage TT with 2000 Hours Playtime and Different to a 5 Year Old TT, with 2000 hours+ Playtime ?
It is generally assumed because of longevity, Vintage TT's are a TT with many more rotations than a lesser aged TT, but this will not be accurate as a assumption.
I have seen TT's with a production from the 00's, with a scored ball at a Thrust Interface, as well as a abraded surface on the a Spindle Wall.
Journal Bearing are very cheap to produce, so why add cost to your product if the customer is accepting of the typically poor quality designs selected for the Journal Bearing.
Thermoplastics are much more suitable as a Bush Interface, as heat is not required to release the embedded low coefficient of friction elements and Metal on Metal is no longer a occurrence.
Adding Oil as a Shaft Fill is a simplistic way of controlling Boundary effect during the rotations, in a shaft with a interface, that has wear developed, but not yet detrimental, the Oil will offer a solution to improving eccentricity during a rotation.
I spent a second set of TORLON bushings and these are performing even worse! Although the fit is better, the noise is more.
The better fit can be easily observed by the vacuum created if the rotor is pulled. There's absolutly no play! Nevertheless more noise is created compared to the first set of TORLON bushings. The noise is definitly created by the spindle-bushing interface. It can already be observed by fitting just the bearing shaft to the rotor spindle and giving it a spin. Some lubricant on the fully assembled unit lowers the noise. A few hours of run in doesn't improve the situation.
Having a last set of TORLON bushings at hand I'll give this a chance, as sson as I've time for it.
The better fit can be easily observed by the vacuum created if the rotor is pulled. There's absolutly no play! Nevertheless more noise is created compared to the first set of TORLON bushings. The noise is definitly created by the spindle-bushing interface. It can already be observed by fitting just the bearing shaft to the rotor spindle and giving it a spin. Some lubricant on the fully assembled unit lowers the noise. A few hours of run in doesn't improve the situation.
Having a last set of TORLON bushings at hand I'll give this a chance, as sson as I've time for it.
I have over the years experienced a lot of Bearing Modifications carried out in the Bearing Housing of TT's.
Most have been Idler Drives and more recent the DD TT's.
I only know of one account where a noise was detected on a brand new Bearing Housing using Thermoplastic Bushes, which was discovered to be a of centre Thrust Pad Interface, which was very easily corrected.
I have even been to homes where the TT owner is willing to put a Stethoscope on the TT to show the noise floor in comparison to a standard unmodified TT.
Not at any time have I been privy to a discussion about a Thermoplastic Bush being the cause of noise, the Torlon Bush is an improved Thermoplastic for role over other types of commonly used Thermoplastics such as Acetal Materials like POM and Peek.
The Torlon Bush fitted to a TTS 8000 I own, has no slop able to be detected by hand, which is very different to how it was, prior to the Bush exchange.
There is no audible sound to the ear from the Bearing on this TT, a Stethoscope used might tell a different story.
I have a few Bush Pairs left, if there is a want to try out another for the purposes of getting the performance myself and others have spoke so highly of from the use of Thermoplastic Bushes, I am happy to send on a pair free of charge.
Note: A correctly machined Bush in Metal or Thermoplastic, where tolerances are kept very tight and the correct lubricant is used, will produce a Interface that will be very very similar in the noise floor being produced.
It is the difficulties with maintaining the correct lubrication, that makes the Thermoplastic attractive, as it will not be creating a Metal on Metal condition when boundary effect occurs or is constantly present.
As for my own TTS 8000 there is now a very good design in place to substantially reduce flexion, other methods used have been interrogated and identified for their failures and where the method seen adopted have undoubtedly been a cause of other unwanted issues relating to a True Spindle Axis and Energy Transferral.
The new design is seemingly addressing 90+% of all the issues that should be a concern, if a full optimisation is desirable for the Bearings Function.
The removal of the Platter Wobble due to the tragic method selected for Spindle / Platter fitting is also a work in progress.
PM me if the additional set of Bushes are wanted to be tried ?
Most have been Idler Drives and more recent the DD TT's.
I only know of one account where a noise was detected on a brand new Bearing Housing using Thermoplastic Bushes, which was discovered to be a of centre Thrust Pad Interface, which was very easily corrected.
I have even been to homes where the TT owner is willing to put a Stethoscope on the TT to show the noise floor in comparison to a standard unmodified TT.
Not at any time have I been privy to a discussion about a Thermoplastic Bush being the cause of noise, the Torlon Bush is an improved Thermoplastic for role over other types of commonly used Thermoplastics such as Acetal Materials like POM and Peek.
The Torlon Bush fitted to a TTS 8000 I own, has no slop able to be detected by hand, which is very different to how it was, prior to the Bush exchange.
There is no audible sound to the ear from the Bearing on this TT, a Stethoscope used might tell a different story.
I have a few Bush Pairs left, if there is a want to try out another for the purposes of getting the performance myself and others have spoke so highly of from the use of Thermoplastic Bushes, I am happy to send on a pair free of charge.
Note: A correctly machined Bush in Metal or Thermoplastic, where tolerances are kept very tight and the correct lubricant is used, will produce a Interface that will be very very similar in the noise floor being produced.
It is the difficulties with maintaining the correct lubrication, that makes the Thermoplastic attractive, as it will not be creating a Metal on Metal condition when boundary effect occurs or is constantly present.
As for my own TTS 8000 there is now a very good design in place to substantially reduce flexion, other methods used have been interrogated and identified for their failures and where the method seen adopted have undoubtedly been a cause of other unwanted issues relating to a True Spindle Axis and Energy Transferral.
The new design is seemingly addressing 90+% of all the issues that should be a concern, if a full optimisation is desirable for the Bearings Function.
The removal of the Platter Wobble due to the tragic method selected for Spindle / Platter fitting is also a work in progress.
PM me if the additional set of Bushes are wanted to be tried ?
@JohnnoG: John many thanks for offering an additional pair of bushings. I'll first sacrifice the last one I've at hand of course! But I may come back to you.
@jamie123: First, both bushings are fitted to the shaft. Than a hand reamer is used. Done in one step. Means reaming all the way through, both bushings in one run, from one direction. Using some lubricant for reaming of course.
I forgot to mention that I even had to reposition the magnetic heads after fitting the second pair!!! Don't ask me why. With the second set in place I was no longer able to lower the platter on the spindle cone w/o it's outer rim touching the magnetic heads.
Best Regards,
Michael
@jamie123: First, both bushings are fitted to the shaft. Than a hand reamer is used. Done in one step. Means reaming all the way through, both bushings in one run, from one direction. Using some lubricant for reaming of course.
I forgot to mention that I even had to reposition the magnetic heads after fitting the second pair!!! Don't ask me why. With the second set in place I was no longer able to lower the platter on the spindle cone w/o it's outer rim touching the magnetic heads.
Best Regards,
Michael
At least it's not an easy task. For hand reaming it's better to use some cutting oil to prevent the reamer getting stuck in the bushings and leaving marks in the surface. I did the first set dry... Further on, for hand reaming I feel it's better to do it in one run to keep both boreholes centric.
Once again I disasembled the motor unit and I'm currently investigating about the source of the noise.
Once again I disasembled the motor unit and I'm currently investigating about the source of the noise.
I re-did the bearing with the two other sets of TORLON bushing at hand. Things are even worse. No chance to get it running w/o noise. It's definitly the spindle-bushing interface causeing the noise as I removed the thrust plate and readjusted its height.
Not sure how to proceed with this. I can reinstall the original bushings or get some new metal bushings. As the dimensions are unavailbale from the shelf, letter have to be maching from standard parts first.
Not sure how to proceed with this. I can reinstall the original bushings or get some new metal bushings. As the dimensions are unavailbale from the shelf, letter have to be maching from standard parts first.
@audiomusica It is not usual to receive feed back about the use of a Thermoplastic being used to separate Metal on Metal at a interface that is typically metal on metal when the lubrication does not create a separation.
I first adopted these methods in a slightly different area of Mechanical Interfaces, being Air Rifle Target Shooting. Prior to going for the Pneumatic System, there were numerous Bespoke Options to create a Spring Powered Air Rifle to have all Metal On Metal interfaces replaced with a Delrin/Acetal Interface. The recoil noise and recoil was substantially reduced.
TT Platter Bearings become a focus of attention for myself in the 90's when I had my first Bearing Housing redesign produced by Martin Bastin. This returned work was enough to show the merits to be had from addressing a Original Design by allowing a mechanically minded person to add their design to the part.
The interest in Bearing assemblies has evolved through owning other TT's and having works undertaken on their Bearing Assemblies, to the point some are complete redesigns.
I have even been encouraged to use a Stethoscope to compare Bearings undergone attempts to improve them vs Standard untouched Typical Bearings, where there is plenty to suggest the bearing that is successfully improved, is perceived as being much quieter than a typical bearing type.
Across a variety of forums where there is discussion and reports returned on Bearing Assemblies having been worked on, whether the Parts in a condition acceptable to be reused, exchanged to New, but close to the equivalent of the original, or in Our Case, exchanged to a New Material being a Thermoplastic.
I have no recollection of any reports claiming audible noise was a cause for a concern, some of these reports are even making known a Stethoscope has been used to detect audible differences.
All recollected reports are of the type, where it is made known, the work undertaken has been worthwhile and wanted to be maintained.
I have no recollection of any individual claiming they would prefer to revert back to the earlier used version.
It is difficult to advise on the way forward with the Thermoplastics you have access to, why the interface in this case, is able to produce noise that is audible / noticeably audible ?, is very difficult to understand. It was never foreseen that a exchange of parts could create a condition that was to be concerning in relation noise. The tightness of fit between parts was the only issue, that has been foreseen as being a concern, and a description for this occurring has already been shared.
If you are considering the return to a Metal Bush, Sintered Iron may be well worthwhile considering, as there is a increased volume of impregnated lubricant available in this design. It is also claimed ( worth checking up on) that there is improved damping properties from this material in comparison to other sintered metals. It is advised they are interfaced with a Hardened Material Face, the TT's Spindle offers this property.
https://snapklik.com/en-ca/product/09SP4P47OUY45
I first adopted these methods in a slightly different area of Mechanical Interfaces, being Air Rifle Target Shooting. Prior to going for the Pneumatic System, there were numerous Bespoke Options to create a Spring Powered Air Rifle to have all Metal On Metal interfaces replaced with a Delrin/Acetal Interface. The recoil noise and recoil was substantially reduced.
TT Platter Bearings become a focus of attention for myself in the 90's when I had my first Bearing Housing redesign produced by Martin Bastin. This returned work was enough to show the merits to be had from addressing a Original Design by allowing a mechanically minded person to add their design to the part.
The interest in Bearing assemblies has evolved through owning other TT's and having works undertaken on their Bearing Assemblies, to the point some are complete redesigns.
I have even been encouraged to use a Stethoscope to compare Bearings undergone attempts to improve them vs Standard untouched Typical Bearings, where there is plenty to suggest the bearing that is successfully improved, is perceived as being much quieter than a typical bearing type.
Across a variety of forums where there is discussion and reports returned on Bearing Assemblies having been worked on, whether the Parts in a condition acceptable to be reused, exchanged to New, but close to the equivalent of the original, or in Our Case, exchanged to a New Material being a Thermoplastic.
I have no recollection of any reports claiming audible noise was a cause for a concern, some of these reports are even making known a Stethoscope has been used to detect audible differences.
All recollected reports are of the type, where it is made known, the work undertaken has been worthwhile and wanted to be maintained.
I have no recollection of any individual claiming they would prefer to revert back to the earlier used version.
It is difficult to advise on the way forward with the Thermoplastics you have access to, why the interface in this case, is able to produce noise that is audible / noticeably audible ?, is very difficult to understand. It was never foreseen that a exchange of parts could create a condition that was to be concerning in relation noise. The tightness of fit between parts was the only issue, that has been foreseen as being a concern, and a description for this occurring has already been shared.
If you are considering the return to a Metal Bush, Sintered Iron may be well worthwhile considering, as there is a increased volume of impregnated lubricant available in this design. It is also claimed ( worth checking up on) that there is improved damping properties from this material in comparison to other sintered metals. It is advised they are interfaced with a Hardened Material Face, the TT's Spindle offers this property.
https://snapklik.com/en-ca/product/09SP4P47OUY45