Adjustable Torque Screwdriver for cartridge screws

[VPN]

Hello,

I have read that the precise amount of torque that is applied to the screws that fix the cartridge is very important, and that minute changes, as small as 0.01Nm, can make a diffence in the sound. One Linn dealer described his use of a Sturtevant Richmont CAL 36/4 adjustable torque wrench to precisely set the screws and find the best setting by ear.

http://forums.linn.co.uk/bb/showthread.php?tid=8068

Anybody here with experience in calibrating the torque of cartridge screws? What would be the best setting for a Lyra Atlas on a Schroder LT?

If this is indeed the case, maybe we could make a table listing the best torque for certain cartridge/tonearm combinations. I suppose it will also depend on the cartridge screw used, in case it is not the standard one provided by the manufacturer.

Cheers,

VPN

 

[Mosin]

I suspect that the idea has some merit, although the screw itself can be problematic because the threads are not polished to a level that they won't grab a bit along the way. Burs so small that you can't even see them can cause a small amount unequal resistance when tightening the screw, so I believe that the ear is still best.

It brings up an interesting subject, however, and that is the difference that having evenly applied torque makes everywhere in the front end. For example, I use 10-32 rather than 10-24 screws to hold my bearing well in place because the finer thread allows more control. I also polish the threads. I use an air driven screwdriver that has a relatively precise clutch to tighten them. It adds to my costs, but I believe it is worth the extra effort. Then again, maybe we are just too OCD. Who knows?

 

[VPN]

Hello Mosin, Thanks for the input.

It seems to me that the ears will be used for measuring/finding/feeling the best audio setting in any case. Perhaps the point here is to use a good adjustable torque screwdriver in order to help make very small changes to find the optimal point, instead of using a torque estimate given by a persons tactile sensitivity using just the hand and fingers.

I think this is analogous to using an USB microscope to measuring and finding the best SRA. The best sounding position will be determined by ear, and it will probably be close to 92 degrees, but the microscope is used to help make repeatable, measurable, very small changes to find just the best spot.

So one question that comes to my mind is: How much difference do you hear from a cartridge that is screwed not so tight vs. super tight? What differences do you hear?

Perhaps important changes may be heard from 0.5Nm torque vs. 1.2Nm torque? If there is much difference, perhaps 0.92Nm is exactly the absolute best in a certain case (of cartridge/tonearm/etc), that one would only find by luck or by using a precision instrument to make very small torque increments, while listening to hear what sounds best.

 

[Johnny Vinyl]

I never over-torque anything, but hey I'm up for a little more screwing if that's what it calls for!


I couldn't resist....you left me no choice

 

[VPN]

Johnny, Considering that a cartridge has two holes, the point here is how forcefully one should screw each of the holes.

 

[jfrech]

Albert Porter over on Audiogon sells these. He says it's a difference you can hear....he has a Altas (but with SME arm)...maybe he has some thoughts on the proper amount of torque...

I may buy one and play around with it soon...

 

[VPN]

John,

Thank you! I will contact Albert. He is a great guy.
Cheers,

VPN

 

[jfrech]

John,

Thank you! I will contact Albert. He is a great guy.
Cheers,

VPN

Albert is...very great. Found a link for you

http://www.porterhouseaudio.com/index.php?option=com_content&view=article&id=59%3Ahex&Itemid=74

 

[rockitman]

Albert is...very great. Found a link for you

http://www.porterhouseaudio.com/index.php?option=com_content&view=article&id=59%3Ahex&Itemid=74

Sounds great on paper...what are the torque specs from each cart maker ? I have never seen any specs published in this regard. I suppose this tool will allow for even torque spec for each screw...that is about it.

 

[mauidan]

The Wheeler Engineering Fat Wrench could be used for this and adjusted to the specs of cartridge maker:

http://www.btibrands.com/product/fat-wrench-with-10-bit-set/

I use my mine to check the fasteners on my speaker drivers.

 

[GaryProtein]

If you REALLY think you need a precise torque limiting screwdriver, THIS is what you need.

http://www.kctoolco.com/wiha-adjustable-torque-vario-s-0-1-0-6-nm-p/28550.htm

The torque is exactly the range you need for cartridges--0.1 to 0.6 Nm

I cannot imagine needing any more torque than this for a cartridge. Dental implant reconstructions are usually tightened to only .35 Nm (35 Ncm), some at only .15 Nm (15 Ncm) and they don't get loose. The stresses on a cartridge are very low and the quality of contact in machining on the mounting surfaces on the cartridge and tonearm shell is MUCH more important than screw torque

Ordinary screws (and their retaining nut) can be "polished" by tightening them to full torque several times and loosening them before leaving them at full torque.

You might also find this information on thread classes interesting:

http://www.accuratescrew.com/TechTips/?TipNO=5

 

[Mosin]

If you REALLY think you need a precise torque limiting screwdriver, THIS is what you need.

http://www.kctoolco.com/wiha-adjustable-torque-vario-s-0-1-0-6-nm-p/28550.htm

The torque is exactly the range you need for cartridges--0.1 to 0.6 Nm

I cannot imagine needing any more torque than this for a cartridge. Dental implant reconstructions are usually tightened to only .35 Nm (35 Ncm), some at only .15 Nm (15 Ncm) and they don't get loose. The stresses on a cartridge are very low and the quality of contact in machining on the mounting surfaces on the cartridge and tonearm shell is MUCH more important than screw torque

Ordinary screws (and their retaining nut) can be "polished" by tightening them to full torque several times and loosening them before leaving them at full torque.

You might also find this information on thread classes interesting:

http://www.accuratescrew.com/TechTips/?TipNO=5

Very good post.

 

[rockitman]

The Wheeler Engineering Fat Wrench could be used for this and adjusted to the specs of cartridge maker:

http://www.btibrands.com/product/fat-wrench-with-10-bit-set/

I use my mine to check the fasteners on my speaker drivers.

Like your avatar...this masters has shaped up for an intiquing finish. Jordan should win....tiger impressive all things considered..

 

[Mike Lavigne]

I have one of these puppies for working on my bicycles. a bit of overkill but with carbon fibre frames I wanted to be precise.

but the minimum it does is 1 foot pound = 12 inch pounds = 1.355817948 Newton Meter.

it is a fine instrument and calibrated recently to + or - 0.25%.

 

[c1ferrari]

If you REALLY think you need a precise torque limiting screwdriver, THIS is what you need.

http://www.kctoolco.com/wiha-adjustable-torque-vario-s-0-1-0-6-nm-p/28550.htm

Ordinary screws (and their retaining nut) can be "polished" by tightening them to full torque several times and loosening them before leaving them at full torque.

You might also find this information on thread classes interesting:

http://www.accuratescrew.com/TechTips/?TipNO=5

Gary,

Thanks for the post. I actually have a similar product -- Wiha set with three torque handles of various range. Curiously, I compared one of the Wiha torque screwdrivers with one of a similar torque range from PB Swiss Tools...they definitely felt different Both Wiha and PB Swiss Tools arrived new with factory calibration.

 

[VPN]

Sounds great on paper...what are the torque specs from each cart maker ? I have never seen any specs published in this regard. I suppose this tool will allow for even torque spec for each screw...that is about it.

Hello Christian,

I understand that we don't currently know, from the manufacturers or among audiophiles, or share what is the best screw torque for each cartridge/tonearm combination. If we start using these adjustable torque screwdrivers, we cand begin sharing this information.

I ordered one: http://www.judgetool.com/cal364micrometeradjustabletorquescrewdriver.aspx

I am curious to know how much difference people hear and what kind of changes are heard, from using more or less torque for different cartridge/tonearm combinations, for example, for the ones you have: Koetsu Coralstone/Graham Elite, etc. If people can share this information and the best torque settings for each combination, it would be great.

Cheers,

VPN

 

[VPN]

If you REALLY think you need a precise torque limiting screwdriver, THIS is what you need.

http://www.kctoolco.com/wiha-adjustable-torque-vario-s-0-1-0-6-nm-p/28550.htm

The torque is exactly the range you need for cartridges--0.1 to 0.6 Nm

I cannot imagine needing any more torque than this for a cartridge. Dental implant reconstructions are usually tightened to only .35 Nm (35 Ncm), some at only .15 Nm (15 Ncm) and they don't get loose. The stresses on a cartridge are very low and the quality of contact in machining on the mounting surfaces on the cartridge and tonearm shell is MUCH more important than screw torque

Ordinary screws (and their retaining nut) can be "polished" by tightening them to full torque several times and loosening them before leaving them at full torque.

You might also find this information on thread classes interesting:

http://www.accuratescrew.com/TechTips/?TipNO=5

Gary,

Thank you. My understanding from reading the posts of the Linn dealer in the thread that I posted, is that he believes that for some metal cartridges it is best to use higher torque, closer to 1.0Nm, so he recommended that other adjustable torque limiting screwdriver. I don't know if he is right or wrong, but this is what I understand he said.

Have you experimented with different torque for the screws of your cartridges? What changes did you hear?

Cheers,

VPN

 

[audio.bill]

Rega makes a torque wrench for their cartridges and recommends it set to 0.4Nm, which is four clicks when using their wrench. I cannot find it listed on Rega's site but did find it shown at one of their dealers here for your reference. Of course different cartridge manufacturers and designs (i.e. plastic vs. metal mounts) would likely call for different optimal torque settings.

 

[VPN]

Rega makes a torque wrench for their cartridges and recommends it set to 0.4Nm, which is four clicks when using their wrench. I cannot find it listed on Rega's site but did find it shown at one of their dealers here for your reference. Of course different cartridge manufacturers and designs (i.e. plastic vs. metal mounts) would likely call for different optimal torque settings.

So Rega seems to be ahead in this regard. It would be great if the other manufacturers could do the same. I don't know if the best torque would change much depending on the tonearm, but if it does, the recommendation should be cartridge/tonearm combination specific. If the manufacturers don't post this, if it makes a meaninful change, audiophiles should post this at WBF.

Cheers,

VPN

 

[jfrech]

So Rega seems to be ahead in this regard. It would be great if the other manufacturers could do the same. I don't know if the best torque would change much depending on the tonearm, but if it does, the recommendation should be cartridge/tonearm combination specific. If the manufacturers don't post this, if it makes a meaninful change, audiophiles should post this at WBF.

Cheers,

VPN

+1 seemingly everything is audible in our high rez systems. Maybe this is one more parameter to get right...Also i wonder if the different metals in our headshells or tonearms effect this also...so one torque setting for one tonearm...a diff setting for a differing arm...