[Delta Wave]

  There was also a plastic tripod that clamped on the spindle.  I forget what that was called.
neo

I'm pretty sure that was an Eon, then later Audio Technica 'Pod'. They always reminded me of the little white plastic things that come in cheapie pizza boxes to keep the box from sticking to the pizza.

[Gentleby]

On fleabey, weights are advertised as clamps most of the time.  It can be confusing for the uninitiated.

There are 2 basic types of clamps, ones that hold down the record and keep it from slipping on an acrylic or metal platter, and reflex clamps.  The Michell clamp can be used either way.  It comes with a felt washer that you can put under the record and use reflex action to partially flatten a warped record or create a kind of pressure coupling of the record.  I have one of these, but I never use the washer. I also have a Sota reflex clamp that is designed for the Sota platter, though it can be used on most tables. I have the Sota disassembled, I plan to use the platter/bearing for a custom table. The clamp comes in handy for my DIY record cleaning machine, where I mostly use it.

The Clearaudio Cleaver clamp just holds down the record.  I'm pretty sure it was originally the Souther Cleaver Clamp and was designed to work with the Souther linear arm which rests on top of the spindle. Clearaudio bought Souther and and now makes both.  I guess John TCG was right about inflation from the '80s till now.  The plastic disc was originally $10, and now $30.  Sorry to digress, but it seems to me it was originally worth about $5, and now maybe $15, but after all it's an audiofool product.

Most conventional mats don't require the use of a clamp, and of course opinions about that vary. Back in the day there was a little rubber clamp that looked like a chess pawn only a little bigger. It was called the Pig - maybe $5.  There was also a plastic tripod that clamped on the spindle.  I forget what that was called. Most high end tables that come with acrylic, delrin, methacrylate or metal platters require a clamp or weight.
neo

Hi,

I'm new to this forum. I discovered it while searching informations about clamps.

This is a question I often ask to myself: are those clamps used to prevent the slipping of the LP on the platter to damage the platter or does it have only sonic qualities?

If anyone knows...

Thanks

[neobop]

Hi,

I'm new to this forum. I discovered it while searching informations about clamps.

This is a question I often ask to myself: are those clamps used to prevent the slipping of the LP on the platter to damage the platter or does it have only sonic qualities?

If anyone knows...

Thanks

Hi Gentleby, welcome to the monkey house.

I don't see how either a clamp or record slipping can damage a platter, if that's what you mean.   Maybe I misunderstand the question? 

There are sonic implications of clamping which go beyond the obvious slippage.  Vibrations from the stylus travel through the record.  The application of a clamp or weight will affect the propagation and damping of those.  Applying a weight or reflexing a record is said to also affect the resilience of the vinyl and thus, the way the stylus reacts to the groove. 
This is heady stuff, but if you listen, you should hear a damping affect, possibly better focus.  Whether or not this is desirable, or how much, is a matter of taste and equipment.

If you want to try one, here's an inexpensive clamp with a rubber insert and a nifty bubble level on top:
https://www.kabusa.com/usagrip.htm

neo

[Gentleby]

Thanks for the tip, Neo. I might try a KAB clamp. And thanks for the welcoming.

Yes, that was my question: I wondered if a record slipping could damage an acrylic platter. Thus a clamp would be useful not only for sound but to prevent the slipping as well. Maybe I being too anal.

Well, anyway, I was thinking of getting a clamp for their sound qualities first.

All best

[xsb7244]

YNWaN has been working on record clamps for many many years.

http://www.audioflat.co.uk/phpBB3/viewtopic.php?f=7&t=84

[mix4fix]

Is there a clamp weight versus motor torque ratio we should abide by?

[neobop]

Is there a clamp weight versus motor torque ratio we should abide by?

Not really, trial and error or common sense?  Too many variables for a set ratio (platter weight, bearing friction, drive belt flex - tension).  Most clamps are lightweight.  Weights, on the other hand can be quite heavy.  The Michell clamp is light and you have the option of reflexing, or not.  The new one is made of Delrin.
http://www.needledoctor.com/JA-Michell-Record-Clamp

neo