Beogram 5500 tonearm travel

[Kurt Kremer]

Has anyone ever had issue with the plastic gears involved with transporting the tonearm getting worn?  The first symptom I noticed was a shudder of the whole tonearm assembly as it reached its home/stop-resting position.  Taking it apart I’d say the wear is more pronounced on the main drive gear but there is still some on the string-pulley-gear.  Not sure this is a primary or secondary cause. Otherwise, the table works well.  No other broken parts noticed but manually running it (power-disconnected) through the mechanical dance of start and stop it’s easy to notice the gear “skipping” right at the end of travel in both directions. Changing the eccentric to loosing and tighten the string varies the amount of “skipping” that occurs, but it always happens.  I sure don’t see too many sources for those gears otherwise I’d be tempted to shotgun them.  Got this table cheap from a source that knew nothing of its history so just in the guessing phase now.

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[Kurt Kremer]

After cleaning and really close inspection, it almost seems like the gears are made this way. The “wear pattern” I speak of initially is too consistent without noticeable scrape marks or shards of plastic.  See movie.  It would be great if someone out there also had one apart and saw the same thing.

 

 

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[Dillen]

The two black cables that runs to the carriage is held firmly to the chassis by a small plastic “bridge”.
Pull the two cables just 4-5mm towards the carriage.

Martin

[Kurt Kremer]

Martin thank you for your reply.  After moving the carriage assemble back and forth 2 thousand times, I finally had noticed that the cables seem to be contributing (variably) to the resistance near the end of the movement.  I had done exactly what you suggested and further noticed that the clamp would not keep the cables from walking back the other way, so I pulled them out and applied a little adhesive to keep them from moving.  Additionally, the larger cable hold-down “guide” seemed to be installed upside down when compared to a couple other pictures I found on the Internet.  Flipping it seemed to give the cables a little more breathing room. I also found I could lessen the carriage movement force by adjusting the free-length of each cable (before applying the adhesive) so that they remained separated throughout their travel and not bind up against each other.  I appreciate the message that confirms this delicate movement is very finely designed. Perhaps there is a less-stiff material that could be applied instead of the current sleave?  Anyhow it seems to be much improved.  I sure focused on the wrong things for a while.  Fun to learn – I do like the table.  I’ve got a 4002 and 4004 that I like better, but this one will be a great starter table for a friend of mine.

Kurt

[Dillen]

I also add a dab of glue to hold the cables in their new position.
Else they will work their way back.

Martin

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