DIYbanter - View Single Post - Bose laser-more info

Jon Elson[_3_]

wrote:

So I took apart the case of the Bose so I could clean and lube the
laser assembly. Also used some canned blow off gas to blow any dust
out of the area between the laser and the underside of the lens. After
reassembly the player worked beautifully. The one particular CD played
right off the bat. But after swapping it or another CD, which also
played, and then putting the stubborn CD back in, it refused to play.
I noticed that when blowing out the laser assembly the lens would move
down because of the pressurized gas blowing between the lens and
laser. So I pressed down on the lens and tried the CD again. Worked
great. After stopping the player and re starting the CD wouldn't play.
Pressing down the lens carrier on the left hand side of the lens
carrier and then trying to play the CD works. After stopping and then
starting the CD won't play. But then pressing down the lens carrier on
the left side makes the CD play again. Anybody have any guesses why
this is happening? It looks to me like the lens carrier is just
suspended by 4 spring wires. But maybe there is something else that
might be dragging. Anybody know how the things are really made?
The lens/laser/sensor assembly is mounted on a veritcal slide and a focusing
servo runs it up and down until it gets the signal from the disc. It sounds
like the slide mechanism is sticking, if of that design. If totally
suspended by springs, and no vertical slide mechanism, there may be dirt, or
maybe the air blast bent the springs a bit. Anyway, it definitely sounds
like the focus mechanism is sticking, so see if you can find out why that is
happening.

Jon