Hi, the nut at the base of the spindle is carefully adjusted at the factory to set up the bearings and it's locked in place with glue. This is fairly soft when the arm is new, but sets rock-hard with time.
I have several suggestions:
1 - TAKE APART.
This risks ruining it, but in this case could be worth a try.
- Prise the plastic covers off the screws that hold the antiskate cover in place (these look like part of the moulding) and unscrew them.
- Loosen (but don't undo) the locking nut a couple of turns. If you are unlucky, the nut will stay in place and the arm yoke will unscrew instead, which is a major problem. You may now be able to press out the shaft, bearing on the nut, not the shaft. The brass shaft is very easily bent and the thread damaged. If someone has already had a go at it, it might already be ruined. The shaft may be very tight. The antiskate magnet should be removable but is sometimes stuck solid, in which case you must be very careful not to break the plastic cover.
- You can now drift the bearings out of the base, clean everything up and replace them. RS (http://www.rswww.co.uk
) have the right ones. I have them if you have trouble getting some.
- Setting up the bearings needs care and practice. They should be very lightly lubricated, but not really "oiled". It's best to take the shields out, oil blow them out and drain them on kitchen towel for a couple of hours. Lock the bearing nut with "locktite"
2- Send it to John at Audio Origami.
Best option really, he's done dozens of these and is is one of the very few people who can put one of these back together again properly.
3 - I have a "service kit"
These are Genuine 2009 spec Rega RB251 bases complete with antiskate and arm yoke, ready to drop the arm tube straight on. It includes new armtube bearings, bearing stubs and caps. This is NOT a Rega-supported option!
4- Easiest option:
I do an exchange of broken arms for a new RB251! You could do this if the take-apart goes wrong.