How best to eliminate LP warps

@terry9 , now try turning the record over.

@pindac , I really wish I had some of whatever it is you are smoking. I wish I had that kind of ...energy.

Tea Total is the Key, no fantastical stuff, followed by just a pure curiosity to learn a little about the what would be the best for the Vinyl Source.

For me it lead to the best environment that a Stylus can be functioning in.

In a very layman description, Vinyl Condition and Cleanliness/Purification within the Groove, Operational Energies Transferred to the Styli, Energies Transferred from the Styli.

I am fortunate to be able to have a support form very adept individuals, who are known for being able to produce methods or carry out work that reduces the effects of the above.

To receive a demonstration of a Vintage TT, with a modified bearing housing, using Modern Materials machined to be a best fit and have a lubrication that is hydrodynamic, is something when encountered is quite indelible, it is as memorable as the song 'Summertime', and has a similar impact, as once heard, one is happy to hear more. 

I have a friend who took these ideas, to a further level and had a Spindle Produced that has a Steel section within the Bearing Housing and a option to use a Variety of Materials that are in contact with the Platter, there material of choice when I was demonstrated this design was Ebony. 

My interest in the subject is no different to a savvy Modern Turntable Producer, they are looking at the similar materials and choosing these to work with their own dimensional tolerances for the materials to interface, this will then allow for their selection of lubrication that best suits those chosen materials and selected dimension tolerances.   

On the subject of a Warp, I have tried out a AT-666 Vacuum Mat and was not satisfied with the sonic trait and how it was perceived as influencing the SQ during the replay.

I do intend on owning a AT-666 and trying it with different materials under it and upon it the LP, to see if the sonic trait can be altered to one that is being perceived as more to my preference. As usual these outcomes are all subjective, and the usual undertaking of later arranged group demonstration, along with the variety of  listening sensitivities that comes with a mixed group,  could easily produce a host of mixed assessments, that are the antithesis of ones own. 

Not being Selfish, the final choice, does belong to the end user, but sometimes the comments made from others, does help with pinpointing traits that one may have been overlooking during their own evaluations. 

 

    

@mijostyn

I have done as you so rudely demanded. With the weight in place, it is perfectly flat on the other side.

I don't like obliging people with facts, only to be treated rudely. Goodbye.

Pindac, Please forgive me if I offended you in questioning the idea that TT bearings and their shafts commonly wear in the horizontal or lateral direction. I only meant what I actually wrote, that I have never seen it or heard from others that it is a common problem. As you may or may not know, I have a fairly extensive experience with vintage turntables, especially DD types, so my query was based on personal experience and past history with Technics, Denon, Victor, and Kenwood DD TTs. I also have extensive personal experience with Lenco and briefly with Garrard idler drive types. (Although there was nothing amiss with the spindle and bearing on my Lenco, because the Lenco was NOS, I did replace the entire assembly with a massive aftermarket spindle and bearing custom made in the UK.) I once commented on your subject by wondering out loud whether the lateral wear problem would possibly occur with a belt drive TT, where there is in fact a lateral force constantly in one direction on the spindle. I certainly do agree with you that vertical wear on the bearing and/or thrust pad is always an issue that should be addressed when one is putting any vintage or "pre-owned" TT into service. We have no disagreement there.

It would seem to me that if the spindle is wobbly in the bearing shaft, there is no solution at all except to replace the entire assembly with new.

@lewm On this forums analogue section there are very few posts from a small selection members, which can appear when an individual beats the drum on a subject, that it is something that is ubiquitous and all are needing to heed the concerns raised.

That is not the case, I am only offering an account of my experiences encountered and nothing else, as said I have been touching base on this subject for many years and have latched onto various information that is in keeping with it as and when discovered.

My earliest experience, where I have shown concern for a bearing condition prior to having modification carried out is when I cleaned out and decontaminated a Bearing, to allow for a Lubrication oil change on a Belt Drive TT, but I would not align that sort of activity with a Bearing Modification.  

As said, I have been interested in the condition of a bearing housing on a owned TT for more than 20 years, this interest started with a Garrard 401, that was sent to a engineer renowned at the time for their work who modified the assembly.

It was this experience that left such a good impression, that made myself be more concerned for a Bearing on a TT, than I would suggest is the common level of concern met, in recent years.

This same type of level of concern has been made toward the Tonearm, and I no longer use certain Tonearms, as I have a arm that has been overhauled, using modern materials and machining tolerances that suit these materials, once more the experience of such design when encountered is a compelling attractor and indelible, especially enough to not want to continue with the other owned Tonearms.

In relation to a TT Bearing, my interest commenced more than 20 years past and during this period, the interest was ignited on a few occasions, but especially through the forum Lenco Heaven.

Through LH, I have been both observing others work and meeting with individuals involved with the forum, who have been working with improving Bearings on the TT's, this work has been observed from many areas and methods used have been duplicated by others.

The Lenco and the Garrard TT's are now able to have Bearing assemblies supplied as Commercially Available Products as an exchange part, that are using the basic principles for the designs produced by the forum members enthusiasts.

The general ideas for the designs are to remove Metal to Metal Contact.

The use of Non Metal Modern Materials used for the role for replacing the originally used metal sacrificial parts, along with a design intent, that  is creating a interface with a accurate/consistent dimensions for the tolerances between the moving an passive parts has been a method that has become quite common in todays bearing assembly designs.

I have been invited in the past to take part in assessing the differences between a bearing assembly on a Idler Drive TT.

Three Bearing were available that are quite easy to swap out, the TT's Chassis had been specially treated to minimise Flexion occurring and effecting the Bearing Spindle.

One Bearing was original with an added lubrication only to a Bearing Housing.   Another version was a overhauled Bearing Assembly, based around the original. The other version was a Modern Material designed Exchange Bearing with a Composite Spindle and where Hydrodynamic Lubrication was claimed to have also been achieved and the flexion that can occur to a Bearing Housing was substantially reduced.

All the above demonstrations took place on the same TT > Tonearm > Cart' and Mounting Method and the attraction toward the Modern Material Exchange Bearing, with a attention to the Lubrication Method and Reduced Flexion, is a version when encountered is quite compelling, it is an indelible experience, needing to be experienced for longer than the alternative versions. 

What I can suggest without reservation, is that a change of Lubrication Only within the Bearing Housing, is a method I will am not recommending, it the TT is to be used extensively.

To fall into the mindset that a oil change only on a TT that is with a unknown history of usage and the present owner not having any knowledge of the quantity of rotations and the conditions those rotations have occurred in, is a situation that is enough to warrant the notion that a further investigation of the Bearing Assembly would be a good practice. Caution is a best practice to be used, if improveing on the condition within the Bering Housing is wanted to be pursued, a skilled individual in such practices may be best consulted with to be a reassuring support.

When I transferred over from Idler Drives to Vintage DD TT's, I acquired TT's in the usual manner, as I viewed these as projects and purchased at a project value.  To have made a purchase of TT's that have shown a excessive movement from the Spindle was not intended or even considered as the condition that would be most concerning, especially when the play detected is the worse movement I have detected from any spindle bearing I have handled.

It has been this experience that has encouraged myself to make it known that when considering a Vintage Japanese DD TT, that not only the Electronics might present an issue that is a concern.

During my broadening of the discussions on the subject of discovering an unwanted Spindle Movement on DD TT, there has been others come forward and make it known that there has also been similar finding on their owned Vintage DD TT's. On the subject of detecting a play on a Spindle within the Bearing Housing I am not alone, having a few Compadre from across the Globe reporting on a similar finding. 

Again, at no time have I suggested there is a ubiquitous issue with a Vintage Japanese DD TT. 

I happily receive comments from TT owners who are not detecting anything concerning on their owned TT's Spindle, this is the best scenario and is the one I wish for all to encounter.

I happily spend 'some of my time' learning about the overall requirements to get the best from a Vinyl Source, Mechanics, runs parallel with Geometry and Electronics, I am quite balanced across all the necessary disciplines to be understood, and choose the parameters that are the most attractive to myself.  

I share my experiences and reference the experiences of others, for the individual leaning toward the idea of purchasing a Vintage Japanese DD TT. It is for the best, if they go into it with their eyes wide open, using the knowledge that is available to them. It is no harm for a wannabe purchaser, or owner of a TT, to be aware that a Bearing Assembly might come with or have a condition that is not ideal, and is another to be  added to the usual concerns seen for the condition of the Electronics.

As always we really want the supplied product to be one with a minimum of markings on a almost pristine Aesthetic, as the only bug bear, but wants and realisation are quite different when it comes to Vintage.