Tangential Arm Floating Magnets - diyAudio
Go Back   Home > Forums > Source & Line > Analogue Source

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 2nd December 2004, 07:14 PM   #1
ebijma is offline ebijma  Netherlands
diyAudio Member
 
ebijma's Avatar
 
Join Date: Mar 2004
Location: Huizen
Default Tangential Arm Floating Magnets

Hello everybody,

Just had a idea.
Would it be possible to let a Tangential Arm Float on Magnets?
Just like a mono rail.
I think this must be possible.
Need some ideas and info on this.
Is this ever tried by anyone?
__________________
Music is what i want, music is what i need
  Reply With Quote
Old 2nd December 2004, 07:41 PM   #2
AuroraB is offline AuroraB  Norway
diyAudio Member
 
AuroraB's Avatar
 
Join Date: May 2001
Location: Norway, -north of the moral circle..
Have never seen it, but have been pondering along these lines myself,,-- something like a Ladegaard with magnetic V-grooves...
Was thinking about an experiment, as I have a bunch of Nd magnets lying around.
With a strong field in the bottom permanent V and some lighter magnets floating atop...

I wonder though, if a contraption like this would affect the PU ??
  Reply With Quote
Old 2nd December 2004, 08:45 PM   #3
diyAudio Member
 
LineSource's Avatar
 
Join Date: Sep 2003
Location: SiliconValley
Default NdFeB arcs

There are very strong NdFeB magnets that are arc shaped, polarized N/S on their curved faces. They can be used to assemble two concentric cylinders with opposing fields to produce a gap - one long magnetic cylinder on the bearing shaft, and short ring on the tone arm joint - you would have a frictionless bearing. BUT you would also have very strong magnetic fields near your cartridge, and hence would likely need some "C" shaped magnetic shielding around the bearing shaft.


One could also wrap a small coil of wire on the edge of the arm joint that could run a small DC current to create a linear motor for anti skating.
Attached Images
File Type: jpg arc_1000_875_45_1000_n.jpg (22.8 KB, 615 views)
  Reply With Quote
Old 3rd December 2004, 08:15 AM   #4
ebijma is offline ebijma  Netherlands
diyAudio Member
 
ebijma's Avatar
 
Join Date: Mar 2004
Location: Huizen
Default Re: NdFeB arcs

Quote:
Originally posted by LineSource
One could also wrap a small coil of wire on the edge of the arm joint that could run a small DC current to create a linear motor for anti skating.
Antiskating?
On a Tangential Arm?
Thats not needed.
__________________
Music is what i want, music is what i need
  Reply With Quote
Old 3rd December 2004, 04:31 PM   #5
diyAudio Member
 
Bill Fitzpatrick's Avatar
 
Join Date: Jun 2001
Location: Eugene, OR
I'm sure there was a previous thread covering this topic.
  Reply With Quote
Old 4th December 2004, 02:58 PM   #6
ebijma is offline ebijma  Netherlands
diyAudio Member
 
ebijma's Avatar
 
Join Date: Mar 2004
Location: Huizen
Here's an idea i found.

http://www.stefanopasini.it/Thorens%...%20Tonearm.htm

Looks funny this turntable.
__________________
Music is what i want, music is what i need
  Reply With Quote
Old 4th December 2004, 06:28 PM   #7
diyAudio Member
 
Join Date: Jul 2003
Location: Bath, UK
Nice idea, but you can't do it as proposed. Google for Earnshaw's theorem - stable levitation with permanent magnets is impossible without some other force providing stabilisation i.e tether, guide rail etc.
  Reply With Quote
Old 4th December 2004, 07:31 PM   #8
johnnyx is offline johnnyx  United Kingdom
diyAudio Member
 
Join Date: Jan 2004
Location: manchester
I saw a demonstration of magnetic levitation on TV which used servo controlled electromagnets suspended above permanent magnets. The feedback system corrected the tendancy to stick to one side or the other. I think they used a microcontroller, but a linear system may be possible. It's possible, but getting this to work would be a project-and-a-half in itself.
  Reply With Quote
Old 6th December 2004, 06:37 PM   #9
diyAudio Member
 
Join Date: Feb 2003
Location: Connecticut
Two problems: the magnetic suspension would be inherently unstable as pointed out above, but even worse, it wouldn't be rigid enough -- the arm would be bouncy in all dimensions -- ack!
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
MG-1 AIR BEARING Tangential Arm audio-kraut Analogue Source 7 24th November 2004 07:55 PM
(+)(G)(-) rails from a floating (+)(-) PS? 2004ex Solid State 4 21st June 2004 05:14 AM
Airpumpless Ladegaard Tangential Arm sreten Analogue Source 31 23rd April 2004 10:58 AM
Floating voltages eeka chu Solid State 12 29th January 2004 03:57 PM
Turntable physics questions-velocity of tangential arm? perfusionist Analogue Source 66 28th December 2003 04:35 PM


New To Site? Need Help?

All times are GMT. The time now is 04:49 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2