Problem with some rumble

[dimkasta]

My SL1200 MK2 is a bit oldish...

The "problem" that I have is that while the record rotates, there is some minor wobbling on the speakers, repeating itsellf in a specific location in the rotation of the platter.

The resonant frequency of my arm/catridge was calculated and measured with a test record at ~11Hz

Visually there seems to not be any problems with the bearing, however I am considering that I need to replace it.

I am using thin singer oil for lubrication

My rack is 6cm plywood flexy style and is not near the woofers. By the way the wobbling occurs even on the end of the disc trail.

Any suggestions before I just quit and buy a new bearing?

[DSJR]

Every record?

Silly request, but please make sure the mat and platter top are clean, as any dirt or gunk will cause slight ripples to the stylus.

May well be the main bearing. The most cost effective 'upgrade' over a replacement stock bearing may well be the Timestep one, where oil is held captive. I dare not advise on the correct oil to use as so many different people have differing ideas..

[Stratmangler]

Every record?

Silly request, but please make sure the mat and platter top are clean, as any dirt or gunk will cause slight ripples to the stylus.

May well be the main bearing. The most cost effective 'upgrade' over a replacement stock bearing may well be the Timestep one, where oil is held captive. I dare not advise on the correct oil to use as so many different people have differing ideas..

The most cost effective upgrade for a stock bearing is to fit an O ring at the bottom of the bearing well.
With the rotational speeds of a TT there are no issues of with oil flinging off the bearing - that's nonsense made up to sell an expensive modified Technics bearing.

[chris@panteg]

The most cost effective upgrade for a stock bearing is to fit an O ring at the bottom of the bearing well.
With the rotational speeds of a TT there are no issues of with oil flinging off the bearing - that's nonsense made up to sell an expensive modified Technics bearing.

Right !!

[Andrei]

The last time I looked a new Technics bearing was about £30 on ebay. Motul 300V Le Mans 20-60 is a good oil but probably quite a few oils would be sufficient. I think KAB USA sell the original oil. It is probably a good idea to service your techie every year or so: Clean inside, use deoxit on the connections, re-oil the bearing.

[Lynster]

I understand the 'speaker wobble' you describe occurs once per platter revolution but does the platter itself appear to rise and fall at its base or edge each revolution (looking across the top deck at eye level). If the conical taper in the platter or the corresponding shaft section have any grit in them, that can cause uneven engagement and the platter itself to wobble.
Can you sense, feel or hear any noise or roughness from the platter or bearing when rotating?

[dimkasta]

It happens with every record.

I have not checked the platter for wobbling. I will later today.

About the o-ring upgrade, I have some 0.5mm teflon discs I can try

About the oil, I tried some 15W fork oil yesterday. It seems a bit thicker than the singer, but still thin. I will try to get some 20W to try today.

Thanks a lot