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Old 5th November 2013, 09:35 AM   #1041
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Have been intrigued by this stiction principle. So in honour of it I found my worst off center lp to try this theory out, have not found a single trace of stiction/sliding of the bearing on glass tube vs rolling as represented. I am as much as anyone very interested in physics and theory but obviously would like to see solutions to a problem. IMHO there is not a problem unless one has built the arm as is and then offered solutions. My apologies if this comes across as crass, but I've been running his for atleast 4 months without even as much as cleaning the tube and it still tracks like a champ .



Colin
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Old 5th November 2013, 11:13 AM   #1042
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Last Saterday I`ve made a visit to the German AAA-Forum Show at Krefeld.

One of the participants: Clearaudio, with their TT2 tonearm.

One word: Fantastic!!

But the Colin`s sound descriptions are just what I heard at Krefeld.

Chapeau Colin.




Hans.

p.s. http://www.aaanalog.de/index.php?con...e:6378#english

p.s.2 check at the end of this week ( google ) for possible foto reports.

Last edited by tomatamot; 5th November 2013 at 11:20 AM.
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Old 5th November 2013, 12:37 PM   #1043
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Why is anyone buying *sealed* bearings??

The seals add friction and are usually used on permanently lubed bearings - the lube installed inside.

They do sell bearings with one side "shielded" if you think you needed that for some reason or another.

Silicone/synthetic oil does not gum up or thicken.

To polish the outside of the bearing I suggest making up an arbor. The arbor needs to hold the bearing between two washers. The washers should just make it to the edge of the outer race. One could use a suitable screw plus a center spacer, then you back the screw up the assembly to clamp the bearing. Now when you spin the bearing on the arbor you do not spin the bearing. One could use clear kitchen wrap (aka "Saran Wrap" in the USA) as a gasket between the washers and the bearing for a better seal.

Do not use "emery" paper, if you were going to use an abrasive you would want to use "wet or dry" Aluminium Oxide. Automotive supply houses sell it in grits down to 2400. If the bearing is pretty smooth already, 2400 grit + oil followed by cleaning (rag is enough) and then polishing compound(s) will give a mirror finish.

I like the ultrasonic cleaner idea.

Don't put your hands in Acetone.
Do not breathe it - or other solvents.
It is a carcinogen.
I know they use it as nail polish remover.
Doesn't change it.
Call back when you are old, you might regret exposure to solvents then...

Most oils will give up when hit with "degreaser spray" those are strong alkaline substances. Water based. You could follow with a water and detergent hot water rinse, and/or repeat this a few times, finally a quick solvent dip if you are concerned about any surface residuals. Hot air (hair dryer?) should pull out any left over liquids.

There are some *waterproof* greases that are really tough to remove. But why did you buy a sealed bearing with grease in it to begin with? Open bearings have a light oil generally speaking. Large industrial open bearings may come packed with some grease, mostly to keep them from rusting on the shelf.

Over speeding these bearings via compressed air with no load should have no negative effect, afaik.
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Last edited by bear; 5th November 2013 at 12:39 PM.
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Old 5th November 2013, 05:26 PM   #1044
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I bought the sealed bearings, cleaned them, used them, they work fine.
Suppose the benefit to keeping them sealed is to keep dust and dirt out.

I've bought another set, and will try them without cleaning.

I've easily over 100 albums on my arm now....its fantastic.
Am thinking of a better TT to put it on.

This is a quick video I've done of my room and equipment.
In it is the tonearm working....please, just critique the arm.


My Room - YouTube
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Old 5th November 2013, 05:38 PM   #1045
Turbon is offline Turbon  Sweden
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Serious setup!

Brgds
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Old 5th November 2013, 08:02 PM   #1046
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Hi all !

There's one thing I would like to mention here , which I believe is food for thoughts :

Altough the horizontal movement goes very smooth with the basics as Colin provided us .. the vertical movement of the wand is not as smooth as one would think . I find out about this when setting the VTF with my digital scale .
I can hardly get to a stable and steady value and the force seem to change each time I lift the armwand and let it down on the scale again .

I think HERE is where polishing the bearingedge could be benificial ! so not at all related to horizontal movement . I have seen linear trackers where this issue has been solved by using either knive bearing seats or another bearing construction .

Could someone chime in on this please ? I can imagine others have noticed this too ??

THX
Paul
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Old 5th November 2013, 08:55 PM   #1047
lexx21 is offline lexx21  United States
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Spinning Wheel... are you using a glass rod and is it completely clean? Also are you using the same sized bearings that Colin used? How much of a deviation are you seeing?
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Old 5th November 2013, 10:08 PM   #1048
kffern is offline kffern  Australia
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Quote:
Originally Posted by spinning wheel View Post

Altough the horizontal movement goes very smooth with the basics as Colin provided us .. the vertical movement of the wand is not as smooth as one would think . I find out about this when setting the VTF with my digital scale

Could someone chime in on this please ? I can imagine others have noticed this too ??

THX
Paul
I mentioned this in my first post. It is even more pronounced with my heavier wire. VTF would change by upto 0.5 gm depending on how I dressed the cable.
My plan is to chop up an old Lenco arm and V block. I have also destroyed an old Japanese arm and have the vertical bearing but it is a bit heavy. I don't think the bearing needs to be ultra smooth though.

My transfi wire is at the post office so should get it on friday. Too many other jobs around the house as well.

Bear,
I agree with open bearings so far. I bought sealed bearings and even after cleaning and spinning up they still aren't as smooth as the open set. These were expensive too, $9.0 each. Unfortunately I have to buy these online and they turned out to be pressed in metal seals that I can't remove. I have 10 sealed (rubber I hope) ordered from ebay hongkong for $3 coming sometime.

Regards,
Kffern
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Old 6th November 2013, 12:14 AM   #1049
bgruhn is offline bgruhn  United States
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Quote:
Originally Posted by spinning wheel View Post
Hi all !

There's one thing I would like to mention here , which I believe is food for thoughts :

Altough the horizontal movement goes very smooth with the basics as Colin provided us .. the vertical movement of the wand is not as smooth as one would think . I find out about this when setting the VTF with my digital scale .
I can hardly get to a stable and steady value and the force seem to change each time I lift the armwand and let it down on the scale again .

I think HERE is where polishing the bearingedge could be benificial ! so not at all related to horizontal movement . I have seen linear trackers where this issue has been solved by using either knive bearing seats or another bearing construction .

Could someone chime in on this please ? I can imagine others have noticed this too ??

THX
Paul
Hi Paul and others trying to sort out the running of these magnificent linear mechanical tone arms.

Here is what I've come up with so far. For starters, go back and reread everything Bo Hansson has written on the subject. IIRC he suggests letting ones ears tell you when the tracking force is correct. For his arms (CANTUS) he never mentions a suggested tracking force. A ball park figure is what I wanted and tried all the tricks in the book to make my LT arm work at some reasonable figure. NO luck, I couldn't measure it. there was always the arm doing what it wanted and not what I thought I was asking it to do. Better results from ignoring the scales and just listening. Then the penny dropped. Never with existing scales and balances will it be possible to measure the vertical tracking force under the dynamic condition of playing a record, especially with the mechanical bearings rolling on the glass tube or rod. But will it be possible to set the counter weight so that when dropping the cartridge from a height that just allows the stylus to graze the recorded track repeatably. I tried it and yes one can achieve this degree of balance. Now take that digital scale you almost threw out and make some little lumps of putty or plasticine that weigh what you are trying to achieve for tracking force. Place a most likely candidate right above the stylus and listen. Once you have seen and heard the results I think you will be amazed at how well your arm tracks with a much lighter weight than you were expecting.

BillG
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Old 6th November 2013, 01:00 AM   #1050
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Quote:
Originally Posted by PDRCanada View Post
This is a quick video I've done of my room and equipment.
In it is the tonearm working....please, just critique the arm.
Fantastic gear and setup you have there PDR!!! And I thought that I was the only person around here that listened to C&W....

Do you have any Zac Brown that you can put up to YouTube???

(not really - just a feeble attempt at humor....)
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