PCE CDROM2/TG-16 gear theory

[SignOfZeta]

OK, so we all know about the little compound gear that ends up with all its teeth shaved off on these OG CD units. Currently there is no replacement (no easy ones, anyway).

And we also know about the problem with CD units (Duos, mostly, it seems) getting somehow stuck at the end of their travel. This has happened a couple of times to me on my Duos. Manually moving the laser back fixes the problem. This has only ever happened to me while playing CD-Rs, and while it seems to be common nowadays, I don't remember ever having heard of it when in the PCE was kicking big time in the pre-CD-R days. This, IMO, is the #1 cause of the "CD-Rs kill PCEs" theory. Exactly why this happens I can't know, but its safe to say that the two most believable theories are that 1) A CD-R takes up a higher percentage of a CD's 5" diameter, therefore the laser ends up further out than usual, and 2) something about CD-Rs cause the PCE/CDROM2 laser mechanism to wig out and to max out its travel for some other reason than there actually being data there out on the edge.

Recently it has occurred to me that these things may be related. Someone may have mentioned this before, if so, credit goes to them. I came up with this theory because I recently had donated to me a broken CDROM2 unit. JBoyPacMan gave it to me and all that was known is that it didn't work. I took it home and opened it up hoping that it might be resurrected by manually moving the laser since it seemed to be at the outside of its travel. When I opened it I discover that, in addition to that problem, several of the compound gear teeth were missing.

Well, 2+2 and all that...its obvious from the condition of the gear that the laser didn't move itself into that position under its own power while in that state, so it must have broken once it was there, probably while trying to get back.

So in other words, what if the leading cause of the shattered compound gear was a combination of the aged plastic and the excessive travel caused by CD-R confusion? In other words, while its not fair to say that CD-Rs kill these drives exactly, it seems like it would be a good idea to not use CD-Rs in OG CD units. Also, it would be a good idea to shoot some lithium grease in there, IMO. The two I've recently worked on were quite dry. Its obvious we need a real solution to this problem (hopefully soon) but until then, an ounce of prevention is worth a pound of cure, as they say.

I'd like to see more discussion on this.

[kattare]

I've seen a total of 4 of the CD units is all, and three of them I bought knowing they were broken, so this may not be entirely accurate, but my experience getting these things on ebay and from forum members has been such:

1 worked out of the box, no problems.  Will not read CDR's.

1 already had the gear broken.  The entire mechanism though was seized solid.  Couldn't spin anything.

2 had a good gears, but the mechanism was seized.  I lubed everywhere I could and slid the gear on the motor up so I would know the motor wasn't causing the resistance.  Kept lubing, wiggling, lubing, wiggling, trying to get the thing to turn just a little bit, but when it finally did... the good gear crumbled and broke.

My theory is that the original lube must eventually get gummy and cause a seize up.  Which then in combination with the aging plastic in that one gear causes it to be under higher stress and eventually break.

If you have a working unit in your possession I would highly recommend keeping it well lubed.

In the meantime, I've been working on streamlining replacing the entire mechanism with a kss-220a.  The one I've done already took 6 hours, I'd like to cut it down to 2 or less.  ;-)

[TheClash603]

I have a working Turbo Duo and I'm an electronic idiot.  Can you please let me know which lube to use and the best way to open the machine and apply it?  I don't need another system breaking on me... 

[SignOfZeta]

I used to always use Vaseline on my CD/LD players and I've never had one break. Recently I switched to lithium grease based on my experiences using it in automotive applications. You can get it at any auto parts store either in a tub with a little brush or in a spray can. From my experience the spray can version varies a lot in consistency from one manufacturer to the next. Some of them come out like water. Whatever you do don't use WD40. I only mention this because WD40 does a great job of marketing their stuff to the casual person. From what I've seen WD40 does a mediocre job of about a million things, but I can't name a single application where it is the best thing to use. There is always something better.

To open the unit you will need a "game bit". I think these are available on eBay. I stole mine from the video store I worked at in the 90s. Once is open the gears are pretty easy to find. Spray the stuff in there (make sure you spay the stuff for a few seconds against a rag or something to get a good flow of the stuff going) and get a decent amount on the gears. Manually move the drive a little to get it spread around nicely. That's about it.

[Zeon]

My theory is that the original lube must eventually get gummy and cause a seize up.  Which then in combination with the aging plastic in that one gear causes it to be under higher stress and eventually break.

I believe we have a winner. From the tg-16 mobiusclimber send me this seems like the likeliest scenario. When I opened it to take a peek inside, the grease (original grease from what I could tell) had turned into cement. No joke, the mechanism is STUCK with no way of braking lose aside from tearing teh entire assembly apart, but with the state of the mech, it's impossible to completely deconstruct without breaking something. In fact in my futile attempts to lube and break the shaft loose, the now VERY brittle gear stripped. The gear was much nastier looking than the working one in my tg-cd. It was almost a shade of brown iirc. My theory is that some of these drives get put into storage for years, and heat and other elements cause the grease to solidify and turn into cement. I also think that the grease they used may be detrimental to the plastic that the problem gear is made of. It has always been theorized that it is made of cheaper plastic from it's yellowish appearance.

In most of the cases that I hear of a tg-cd with a gear problem is that they only occur after attempting to load up a cd after months or years of non use. As strange as it may sound, using they system at a regular interval may be the best way to prevent this from happening. The heat and movement of the drive will keep the grease good for a while. However I STRONGLY recommend to any who still have a working tg-cd, clean off the old grease as good as you can, and regrease with a quality grease. This will probably keep them going longer than anything else.

Also, the tg-cd unit itself does not require a game bit, it uses standard phillips head screws. You are probably thinking of the tg-16 or the dock itself zeta. The duo also used the same security screws. I personally don't recommend a spray type lube, unless you know it's good quality, and refrain from spraying too much. DO NOT, I REPEAT, DO NOT USE WD-40!!! Wd-40 has it's place as a lube, and that's not in game electronics and mechanisms. Wd-40 is especially notorious for gumming up, especially when too much is used. I have heard too many horror stories where people would spray wd-40 in an atari 2600 paddle, which fixed the problem for a while, only to make it near unusable after a good period of nonuse.

I don't know what this lube my dad has that I use, but it comes in a tin can with a lid you pry off (like a paint can) It's green and you grab a tooth pick to get a little and then spread it on the surface with your fingers or a cloth. You can also use various household 3 in 1 oils, just pour a little on and work it into the mech, making sure to clean off excess grease.

[SignOfZeta]

Also, the tg-cd unit itself does not require a game bit, it uses standard phillips head screws. You are probably thinking of the tg-16 or the dock itself zeta. The duo also used the same security screws.

I was addressing TheClash603, who is asking about a Turbo Duo up there.

[kid_rondeau]

Zeta, well thought-out, and well put. Your theory on the relationship between the broken compound gear and CD-R's is an inspiration.
You may have read on a different thread about the possibility of molding a new gear with a kit (and if it works we could expand this to all the gears in the drive)...when I finally have enough time/money to take this on, my plan is to mold them all, so I could make entire sets so folks with these problems could replace the entire drive system.

[skevenna73]

The Turbo Express is the US version og pc engine GT, Therefore the PCE-PRO wont play with the turbo express cause simply... its a US PC ENGINE PCE-PRO works only on japanese machines PC ENGINE, DUO, GT. I have a japanese GT, a japanese duo and a US turbo express. The card works fine on the japanese ones but not on the turbo express To make it work, youll have to mod the machine or buy a japus adapter

[Arkhan Asylum]

what is an OG TG?  im probably going to feel dumb once you tell me.


and yeah the lube on the TGCD units goes gimpy after awhile.   Lithium grease is the way to go.   Ive used the same thing on Commodore 1541 drives which have rails that get very frictiony over the years.  Lithium grease saves the day every time.

as for the CDR theory, I wonder if anyone could make measurements of the length of the data on a CDR, vs. the traveling distances of the CD mechanism.

I'd do it but I can almost guarantee my drawing abilities will yield diagrams that look like picasso art.

[blueraven]

what is an OG TG?  im probably going to feel dumb once you tell me.

"of"

Although my TurboExpress is totally OG.

[SignOfZeta]

The Turbo Express is the US version og pc engine GT, Therefore the PCE-PRO wont play with the turbo express cause simply... its a US PC ENGINE PCE-PRO works only on japanese machines PC ENGINE, DUO, GT. I have a japanese GT, a japanese duo and a US turbo express. The card works fine on the japanese ones but not on the turbo express To make it work, youll have to mod the machine or buy a japus adapter

Whhaaaat?

My use of "OG" refers to "original", as in the TG-16 CD or the PC Engine CDROM2 unit, and not Duos, Super CDROM2s, or Laser Actives. See Original Gangster. This new guy's use of it seems to be a typo, one of several. Also, I have no fucking clue what he's talking about!

[Arkhan Asylum]

oh see I see OG and think Original Gangsta, lol

[Zeon]

OG has always meant Original Generation to me, basically the same meaning as Zeta would use it.

[Nazi NecroPhile]

The 'og' was certainly a typo, but what is this PCE-PRO card he speaks of?  The only thing that I can think of is an Arcade Card Pro, but what the hell does that have to do with the gear and why would anyone care if it will boot on a TurboExpress in the first place?  Isn't this the same dude that asked some fast and furious, wrong wheel drive question?  Methinks that English may not be his first language..... or second..... or third. 

[SignOfZeta]

The 'og' was certainly a typo, but what is this PCE-PRO card he speaks of?  The only thing that I can think of is an Arcade Card Pro, but what the hell does that have to do with the gear and why would anyone care if it will boot on a TurboExpress in the first place?  Isn't this the same dude that asked some fast and furious, wrong wheel drive question?  Methinks that English may not be his first language..... or second..... or third. 

I disagree. His English is so bad he pretty much has to be a mono-lingual, English speaking American.

[oldskool]

I think he meant to reply to another thread.  I've seen that happen before.