Tonearm Movement Problem - SL-1200 Options

[Nav]

First, here's a little video I put together which should describe the issue.

Anyway, I run 2 SL-1200s for my DJ setup. One is a MK2, one is an M3D. the M3D is the one with a problem. The tonearm moves in this manner without any outsides forces acting on it, such as record force or anti skate:

At tonearm rest: movement toward center
At absolute edge of platter: no movement (as it should be)
At midway down the platter: movement towards outside of platter (as though there was a high anti skate acting on it)
At 3/4ths down the platter: no movement
At more than 3/4ths down the platter: movement inward towards the center

Anyone have any ideas what might be causing this? It does it regardless of stylus, cartridge, headshell, orientation, etc.

Thanks

[mjb2006]

You might try also posting in the forum at vinylengine.com.

[Arnold B. Kruege...]

First, here's a little video I put together which should describe the issue.

Anyway, I run 2 SL-1200s for my DJ setup. One is a MK2, one is an M3D. the M3D is the one with a problem. The tonearm moves in this manner without any outsides forces acting on it, such as record force or anti skate:

At tonearm rest: movement toward center
At absolute edge of platter: no movement (as it should be)
At midway down the platter: movement towards outside of platter (as though there was a high anti skate acting on it)
At 3/4ths down the platter: no movement
At more than 3/4ths down the platter: movement inward towards the center

Anyone have any ideas what might be causing this? It does it regardless of stylus, cartridge, headshell, orientation, etc.

If the arm has low friction, then the amount of force required to obtain these results is microscopic. One possible source might be the springiness of the cartridge lead wires. The turntable might also not be perfectly level.

Probably nothing to worry about, if you are obtaining good tracking with test records.

[Nav]

Got it fixed: the screw on the top of the tonearm just needed to be turned a little bit. I'm not entirely sure of it's function, but turning it carefully and observing the adjustments (to try and get it to sit perfectly) fixed my problem.