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Philips CD880 lube

M

Michael Nudelman

Active Member
Hi!


Some over 2 years ago I seriously refurbished a CD880 that had many a woe, including a dent in the backpanel, blown zener in the 10V power supply etc. It worked fine but the sole problem seemed to resurface soon after having been addressed: the table does not want to slide out and needs help.

At the time I used lithium grease without thorough cleaning. Also I changed the driving belt for the new one according to specs (forgot the name but there is a guy with a catalog who sells them; an Americnaq company).
It is not the belt problem as the belt does not slip: the table simply refuses to move at the very initial stage of being extended, where the tray is being raised. If helped during this stage (the motor is not moving and the belt is not slipping) it will then slide out.

This time I decided to take it apart again and clean out the traces of the old grease (lookes yellow like earwax), after which I intend to lube it. My question is to the type of lube I should use, and whether there are multiple types or just one.

I have:

- Lithium grease (Liquid Wrench)
- Lubriplate No. 130-AA Calcium Multipurpose Grease
- Kluber liquid lube (one of the recommended for cintered bronze bushing in motors or idlers in tape decks).


There are a few places that clearly used grease. There are also those where I have not seen any but added some.

So, do I need lube and what type in the following places:
Axes of the two nylon gear parts, the pulley for the belt from the motor (top pin) and the cogwheel for the rack and pinion driven with the tooth belt?

I would put images but I only have the pics on my computer. However, I created a similar thread on AudioKarma, and it has all photos.

https://audiokarma.org/forums/index.php?threads/philips-cd880-lube.1019506/
 
If your player has the CDM1 drive have a look here:

https://nanocamp.de/?revision

Check the PDF for the 204, 304 or 304MKii

If it has the CDM1MKii you probably need to loosen one of the springs which holds down the table, or remove one spring and try with only one spring on one side. Many players have only one spring fitted for that reason...
 
JPK

Thanks for replying.

Yes it is CDM1MKII. Yes there are two springs holding the hub to the CD when closed, and they are the ones that it has trouble overpowering. However at the very beginning when I lubed it in 2020, together with the belt change, it did work. As a last resort, I could loosen or take out one of the springs. I think though, removing a spring will cause the hub to exert a lateral force to the CD hub, so it should only be used after all else has failed.
I will try the lube first.

My main question is to the type of the lube used, originally or preferable nowadays.
 
Here:
Lubricants and possible plastic or rubber compatibility issues - Newgate Simms tech support
Scroll down and you'll see from the table that silicone based grease is compatible with all but silicone elastomers.
There are also plenty of references on www about white lithium grease being suitable and I've also seen Molycote EM-30L recommended.
I have an Arcam Delta 170 with the CDM1 MKII mech and have had the same problem. If you look at the back of the mech, the tray is lifted by a pair of wheels that hang over the back of the mech and I found that the grooves which the wheel axles clip into wear so the wheels drop a bit lower than they should. I also noticed on mine that there is a slight lip on the back edge of the die-cast metal plate. Always meant to try just a light application of a file to remove this lip as I'm certain that this loads the wheels and causes the wear in the clips where the wheels clip into the tray. I bought a S/H motor off someone on here, but it made no difference. Think I ended up stretching the springs (that hold the flap down on top of the CD) slightly to reduce tension, but re-lube might help. Give it a thorough inspection and see what you can find and post photos if you can.
I have no idea what my lube is TBH. Bought off eBay >10 yrs ago as 'plastic safe' or something similar...10ml syringe of semi-transparent stuff, so suspect it's silicone as it resembles (dangerous, I know to make assumptions) some silicone grease I bought as food-safe for my sink taps.
 
a.palfreyman

Thanks, this is the only direct answer I have received by now to the question I asked, on all the forums. The link, I am sure, will also help.
I think I will try the silicone lube first.

My question is two-fold: one is, the compatibility, and two is the consistency, and how would a particular lube affect the operation. While a lube is a lube is a lube, if it is too viscous, it might affect the initial movement (the initial starting friction is always a bit larger than the motion friction).

This more or less gives me an idea.

Speaking of lithium grease: yes, I am sure it is suitable, but I heard it dries up (it is, after all, a soap).

Well, this weekend I will try the silicone. Yes I will publish the photos.
 
Let us know how things go on: I am especially interested to hear if the lube alone solved your problem, or if you needed to carry out additional mechanical invasion...
 
When I worked in printer repair industry Canon recommended MOLYKOTE PG-641 and FLOIL G311S for metal to plastic & plastic to plastic contact, and FLOIL KG-107A oil for metal to plastic no drip, although that was 10 years ago and then they wasn't available for mere mortals as prices was prohibitive and they usually came in bulk volumes.
 
Well, I went through some more similar topics, including this website, Audiokarma and Steve Hoffman's, and then some, and the Molykote EM30-L, as Palfreyman noted, is the one that is recommended by most, so I ordered some from Amazon; should come this week.
 
Well, I wanted to put files with photos, but since I do not have accounts on photo sites, and the photos I have are on my computer, unfortunately (unless I am not understanding it; Audiokarma does allow the pics to be uploaded) I will have to only use words, noy images.

So. I ordered and 3 days ago received the Molykote EM30-ML, and today I went to apply it.

So, first things first, I used Kluber oil to lube the motor's mearing. Not that I think it needs it but won't hurt.

Then I applied the Molykote to:

Both axes of nylon pulley and rack-n-pinion gear cogwheel.
4x grooves in the slide which are used by the CD table to go up and down.
The nylon rollers, every one.
The inclined surfaces the Disk hub holder uses to go up and down.

Then I reassembled the player and tried the slide. No change. Same exact problem as before.

Then I lubed the pins of the Disk hub holder that are used for it to turn when going up and down.
After this I could see some improvement: the table started pulling out, but after 1/3" it would stop. I applied the lube again after extracting the holder, with the same result. Clearly this one was important as this is the only point of lube, which affected the operation at all.

At this point I removed one spring pulling it down, and the slide came out without effort.

So I ended up doing what I thought I could avoid: I stretched the outside spring a bit, and the slide started coming out after this.
Then for symmetry I did the same to the inside spring.

The CD works now after the reassembly. I could see that it is just a tad sluggish when coming out, but comes out nevertheless.

Well, it could use a lube after 30 years plus, and I think it was the right thing to do. However I should admit that the lube itself has not solved the problem.

Two possible causes:

1. The motor has lost the torque.
2. The pins of the hub holder lost their smootheness to the point where even withh the lube the friction is more than it should be.

It plays just as good as it did before.

So, this concludes my efforts.
 
Not saying this is the case but once had Onkyo player with totally worn out loading mechanism gear axle that ejected/loaded only when disc clamp was manually lifted.
Edit: Although when I think again and you say that originally motor was not moving with new belt that would point to motor itself or it's driver, as on mine it slipped even with fresh and too short belt.
 
I decided to take a good look at the driver. I noticed that

1. There is a mistake in the sch (one of the diodes shown backwards).
2. Instead of -6V there is -5V. This lowers the driving voltage by 1V. However, upon the investigation (I actually took the board out to recreate the circuitry), I noticed the LDO that creates the -6V out of -18V, which is supposed to be UA7906, is actually MC7905, which is neg. 5V LDO. The LDO seems to be factory installed so I do not think this was a repair. Also it connects to -10V instead of -18V (which is OK).

So, I am not sure I want to change this, as i am not sure if this was the factory practice for a long time. Whatever it is, it is factory. I could possibly get an MC7906 and out it instead, but as said before.....
 
It's not the reg that's the issue, it's the motor it's driving or the mechanical load placed on the motor, now that you've excluded gears, belts friction etc.
 
aq225917

Well, you are right to a degree: if out of the factory this worked, this is not the reg, because it is up to the org specs.
Now the sch does have discrepancies: I noticed this the very first time when fixing a broken -10V power supply.
Also there are mistakes.
However I could very well see how first they used a -6V LDO from the -18V, and then, for whatever reason,they switched to the -5V made out of -10V. Without backannotatimg the change to the schematic, which still shows -6V out of -18V.
This sure would lower the power dissipation, but the motor works very short time, and a 1A LDO with a heatsink was not likely to be stressed to much.

While all is new and smooth, the -5V to 5V drive (+/-10V therefore) proved to be adequate. However with ageing, parts developing roughness and he motor losing a bit of its original oomph, who knows, maybe that additional 1V would do the trick. After all, the torque is proportional to the current, and the current more or less proportional to the voltage (strictly speaking the speed is). So increasing the torque 10% could be just it.

PS. After sitting in the colder workshop the table requires some help sliding out. I am sure when it is back to the room temp, it will do it on its own.
PPS. One day I just might order a 7906 and try it.
 
PS. And in the meantime, purely serendipitously.....look what I found. Funny. Grease for ONLY CD880. :)

https://www.ebay.com/itm/1342317243...d=link&campid=5338728743&toolid=20001&mkevt=1

Grease Bold for Philips CD 880 CD Player Compact Disc Player
Item specifics
Condition:
New: A brand-new, unused, unopened, undamaged item in its original packaging (where packaging is ...
Marke:
BlackReel
Herstellernummer:
15548.6
Produktart:
Ersatzteile, spare parts
Markenkompatibilität:
Für Philips
Modellkompatibilität:
Für Philips CD 880
Gerätetyp:
CD Player
Produkt(e):
Fett
Device Type:
Compact Disc Player
Product(s):
grease
Kompatible Produktlinie:
-/-
Farbe:
-/-
Besonderheiten:
-/-
Kapazität:
-/-
 
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