Ray H
01-07-2005, 01:49 PM
Rega TTs are justly legendary for their reliability as well as their performance. Still, I thought re-lubing mine after 8 1/2 years' use might be good preventive maintenance. I recently "yanked" the spindle/sub-platter out of the bearing well for a looksee. Don't do this unless you're committed to following through - it's a mess with about 1/2 the factory lube getting sucked up with the subplatter axle. It's THICK, but does DRIP! The factory lube's pungent aroma led me believe it was hypoid gear oil - or something mighty close. I flushed the brass bearing well with several applications of mineral spirits (paint thinner), using a 99 Cent Store turkey baster to extract the flushes. The I dobbed the well with a lint-free cloth to soak up the residual thinner. The sub-platter axle was treated to the same procedure with a clean rag, a few paint thinner soaked rag wipes, and a final drying. I then carefully filled the bearing well with some 80W-90 hypoid gear oil* bought from my local Pep Boys years ago. I filled just past the top of the hardened steel ball thrust bearing in the bottom of the well. I then put the subplatter back in the well and waited. And waited... And waited some more... The sub-platter axle is fit to extremely close clearances to the bearing well so an airlock resulted. I had an elevated turntable on an air-bearing for the better part of an hour before gravity and the glass platter finally forced the subplatter to its resting position! Shining a light beneath the subplatter showed no overflow of oil to the surface. Not good - it meant that once the subplatter was at its rest position, there was still insufficient gear oil to rise all the way to the top of the bearing well. Off came the sub-platter to fill a bit more gear oil. Several more such additional fillings and hours later finally resulted in gear oil oozing out at the top of the bearing well with the sub-platter installed and at rest position. Success! I had prepared for this eventuality with several folded paper towels place against the sub-platter shaft where it exited the bearing well to sop up overflow when it finally materialized.
All my efforts would've been for naught if the oil I substituted for the factory lube was incompatible with this application. Enter the internet. I emailed Rega in Jolly Old, and received a reply this A.M. Their advice was that they use conventional "schedule 80" gear oil. So, it seems my best guess was spot on.
*The gear oil I used is conventional, but, nevertheless, current GL-5 spec. A quart ran about $2.69. All told, I probably used less than an ounce. For the truly obsessed audiophile, synthetic gear oil in that viscosity range could be substituted - mainly for its "feel-good" factor IMHO. Synthetics are great, but may be serious overkill in this application. They have a naturally higher viscosity index - which means they hold their designated viscosity ("gooiness" for lack of a better term) over a broader range of temperatures - important for heavy commercial vehicles that have to be mobile in sub-freezing temperatures yet still have protection against searing southwestern heat. Since TTs are usually operated within the confines of an air conditioned office or domicile, temperature extremes shouldn't likely be encountered. While synthetics are superior lubes, the Rega's robust, over-engineered bearing design allows even "lowly" conventional lubes to function perfectly well - and probably indefintely at that, too. (At no point did I find even the hint of metallic particulates glinting in strong light during the fluid exchange.) Still, synthetic gear oil would do no harm. Figure a quart of Mobil 1 synthetic gear oil would run about $8.00 at discount - more or less.
All my efforts would've been for naught if the oil I substituted for the factory lube was incompatible with this application. Enter the internet. I emailed Rega in Jolly Old, and received a reply this A.M. Their advice was that they use conventional "schedule 80" gear oil. So, it seems my best guess was spot on.
*The gear oil I used is conventional, but, nevertheless, current GL-5 spec. A quart ran about $2.69. All told, I probably used less than an ounce. For the truly obsessed audiophile, synthetic gear oil in that viscosity range could be substituted - mainly for its "feel-good" factor IMHO. Synthetics are great, but may be serious overkill in this application. They have a naturally higher viscosity index - which means they hold their designated viscosity ("gooiness" for lack of a better term) over a broader range of temperatures - important for heavy commercial vehicles that have to be mobile in sub-freezing temperatures yet still have protection against searing southwestern heat. Since TTs are usually operated within the confines of an air conditioned office or domicile, temperature extremes shouldn't likely be encountered. While synthetics are superior lubes, the Rega's robust, over-engineered bearing design allows even "lowly" conventional lubes to function perfectly well - and probably indefintely at that, too. (At no point did I find even the hint of metallic particulates glinting in strong light during the fluid exchange.) Still, synthetic gear oil would do no harm. Figure a quart of Mobil 1 synthetic gear oil would run about $8.00 at discount - more or less.