8mm Forum: Problem with le take-up of my GS1200

This is topic Problem with le take-up of my GS1200 in forum 8mm Forum at 8mm Forum.

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Posted by Antoine Orsero (Member # 41) on July 03, 2018, 05:16 AM:

Hi,
the take-up does not turn on my GS1200 in the forward direction
If I put the reverse gear it turns when it should be the opposite.
What is the problem?
Thank you very much for your advice

Posted by Chip Gelmini (Member # 44) on July 03, 2018, 09:50 AM:

When you press forward play are everything else moving. Film feeds through OK and only the take up reel fails?

Could be several things. Broken or stripped drive gears to the take up motor and /or drive train* / bad motor fuse / worn brushes inside motor cavity / etc.

Best advice:

Find someone who can service the machine and give it a tender loving care tune up.

I took mine and asked the tech to "restore to factory specifications." He did a fantastic job and charges about $300.00 usd per machine.

These are old projectors - even when serviced they will still not be right or 100% but they will be much better and your issue can be fixed.

* if the film is not feeding through normally then other drive gears could be broken. They dry out after time.

CG

Posted by Paul Adsett (Member # 25) on July 03, 2018, 10:00 AM:

Antoine, It's possible that one (or both) of the relays on the main mother board need replacing. These relays are part of the logic circuitry that control all the mechanical and electrical switching functions and motors of the GS1200. I had the same problem on one of my GS1200'S and ended up having to replace the smaller of the two relays (located close to the fan shroud).
You will have to remove the main board in order to replace them. If you are not very good at soldering, find someone who is.

Posted by Antoine Orsero (Member # 41) on July 03, 2018, 11:07 AM:

Thank you very much Chip and Paul

All the projector works very well! The take-up engine is new and the gears too.
When I press the start everything works except the take-up! If I press the reverse the take-up works at the same time as the rest which is not normal. At some point the take-up started normally and then it stopped! By doing a walk before it did not work anymore. I put in reverse and the take-up turns. I can not understand why. Something escapes me!
The relays are new and have been changed. If they were defective some items would not work! But it's just the take-up that is problematic

Posted by Paul Adsett (Member # 25) on July 03, 2018, 02:06 PM:

Antoine, if this were my machine I would now probably pull out that rear take up motor and its associated gear box. Then examine the gears to make sure they are OK. Then thoroughly clean all the gears and clutch, and re-lube with lithium grease. It is also possible that the little pinion gear has loosened on the motor shaft and the tiny set screw needs to be tightened up, so check that out as well.
Reassemble and re-test the machine.
If there is still a problem it might be the motor and you might have to remove the rotor from the motor and clean everything inside (see separate thread in technical section of forum).
http://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=012165

Posted by Antoine Orsero (Member # 41) on July 03, 2018, 03:04 PM:

Paul
I removed the engine from the take-up and everything is correct. When I start the reverse the take-up works and when I start the walk before it does not work.
So for me it's an electrical or electronic problem.

Posted by Chip Gelmini (Member # 44) on July 03, 2018, 08:54 PM:

I think your issue is a perfect example on how sometimes these machines can be real buggers to figure out I hope you get it sorted soon

I go back to when I said before if you find a qualified tech they might be able to figure it out.

Posted by Paul Adsett (Member # 25) on July 03, 2018, 10:40 PM:

Antoine, try reversing the red and blue wires on the rear take up motor.

Posted by Antoine Orsero (Member # 41) on July 04, 2018, 02:51 AM:

Alas in Marseille the repairers of projectors disappeared
Paul I will try

Posted by Chip Gelmini (Member # 44) on July 04, 2018, 09:33 AM:

As an alternative if you have a second Super 8 Sound projector And enough room to do this try putting the second projector Directly behind the GS 1200Make certain to align both projectors evenly so the film does not scrape against anything and start them at the same time use the Gs to show the movie and the second projector for the take up reel That will keep you going until your other projector is fixed

Posted by Renzo Dal Bo (Member # 5688) on July 04, 2018, 03:19 PM:

Hi Antoine
a few months ago I really have had the same problem. During a projection suddenly the take up reel stopped. Immediately I tried the reverse projection and it worked properly. Then turning again in forward position it normally started to work again. After some minutes the take up reel stopped again. Since that time the problem happened randomly but always with greater frequency. Looking around here and in other forums, I realized, as Paul already mentioned, the biggest Matsushita relay, in the main board is the main guilty suspect. Its contacts get dirty but they can be cleaned with a proper contact cleaner. I took out the main board and desoldered the main relay. Just now it can be opened removing carefully its transparent cover for cleaning. After reassembly, at least for now, the projector never showed this problem again. For safety I ordered a new relay, but I have to warn you that many eastern sellers sell used refurbished relays declaring them new.

Renzo

[ July 04, 2018, 06:19 PM: Message edited by: Renzo Dal Bo ]

Posted by Nantawat Kittiwarakul (Member # 6050) on July 04, 2018, 08:13 PM:

I'll bet with my (small) fortune that the problem lies in the relay - dirty contact to be precise. That explains why it operates normally in reverse,since it is less often used in that regard hence less contact wear.

If possible try bypassing the whole relay (temporary replacing it with manual toggle switch,for example) to see if the rest of the system is still alright. If yes then replace the relay,problem solved. [Razz]

Posted by Antoine Orsero (Member # 41) on July 05, 2018, 02:09 AM:

I thank you all for your advice. I tell you that these relays are new and were purchased at Van Eck video service. So it can not come from relays. I have a second GS1200 that works for the moment but I prefer the ST1200 which are less fragile. That's two GS1200s that are broken down! I keep them for spare parts. Thanks again. Best regards.

Posted by Phil Murat (Member # 5148) on July 05, 2018, 03:36 AM:

Hello Antoine,

I have experienced this issue on my GS1200 too,and also as an intermitent fault.

I suggest you to clean the small "ratchet gear" inside after arm (to gain acces, just remove cover).
Do not renew grease in that case, just keep it dry and free.
Ratchet assembly could be a bit jammed due to dry grease and unlatched from time to time....

Provide us with result as necessary.

Phil

Posted by Antoine Orsero (Member # 41) on July 05, 2018, 04:34 AM:

Hello Phil,
Thanks Phil,
I removed the engine from the take-up and I connected the electrical wires: The engine runs very well but upside down when I put the reverse gear but not when I put forward. So for me it's not a mechanical problem but electrical or electronic .
Best regards

Posted by Phil Murat (Member # 5148) on July 05, 2018, 08:30 AM:

Antoine,

Could you make this simple check / test :

-Even your relays were recentlly renewed , While your machine is running , setted "Fwd" , "gently" hit crystal shells relays (juste to vibrate relays) , one by one (with a nylon stud or equivalent) and report any change concerning rear take up reel motion.

Let us know

Posted by Paul Adsett (Member # 25) on July 05, 2018, 10:58 AM:

I still think Antoine should try reversing the red and blue wires to the take up motor.

Posted by Chip Gelmini (Member # 44) on July 05, 2018, 01:19 PM:

On the subject of relays, would a bad relay cause the machine to "start and stop" several times while playing a reel all on it's own? I have a GS that does it once in awhile. It was reported to the tech but NATURALLY did not happen while he had it. And likewise, it did it recently AFTER it was back from the shop.

It does have to go back soon for something else, so I'll have him take a look at it. I guess I already paid the bill, so the repair should be under the 90 day warranty. Whew. [Big Grin]

Posted by Paul Adsett (Member # 25) on July 05, 2018, 02:41 PM:

Chip, I think the answer to your question is yes, a bad relay can certainly cause intermittent operational issues like you have described.

Posted by Antoine Orsero (Member # 41) on July 05, 2018, 02:53 PM:

Paul,
I will try but it is not normal. The red threads go together and the blue threads too
Chip,
I agree with you. A capricious relay does this kind of thing that you describe! I did not give up and did not say my last word!
Thank you very much

Posted by Thomas Knappstein (Member # 6134) on July 10, 2018, 11:30 AM:

There could be the Carbon Brushes at the End of their Lifetime.
Than they havent enough Contakt to the Kolector and sometimes the Motor stops. If you open the Motor you can see if the Brushes are to short. Put new ones in and it run for the next 40 Years.

Posted by Antoine Orsero (Member # 41) on July 11, 2018, 09:22 AM:

Thomas,

Thank you for your reply! But this problem has nothing to do with coals. If it did, the engine would not run! But it turns upside down when I put the reverse gear on and not while walking forward. In my opinion it is an electrical or electronic problem that I have not yet detected

Posted by Thomas Knappstein (Member # 6134) on July 11, 2018, 10:20 PM:

Than there are two Things what it could be.

1. The bigger Relais on the Main Board is failed

2. The forward Transistor on the Take up/Rewinding control Board is failed.

You can check the input Voltage into this little Board when push forward. If there is 8V the Relais is oK. If not the Relais has a switching Problem.

Posted by Antoine Orsero (Member # 41) on July 12, 2018, 03:42 AM:

Thank you very much,
I have the impression that the failure comes from this little thing next to the engine before seeing photo

Posted by Thomas Knappstein (Member # 6134) on July 17, 2018, 06:27 AM:

Hi Antoine!
There is one Thing you can do to find out if it is a mechanic Problem with the Gears. Change the blue and red Wires of the take up Motor wich is near the Transformer. Now press the reverse Button. The Machine (without Film of course) is running reverse and the both Spindles must be turn. If they do there is no mechanical Problem with the Gears. Now change the blue and red Wires back to original. If you press now forarding and look at the two Motors, do they turn both or only the reverse one? This two motors are ever turning both. In Forward and Reverse. And you must check the Voltage on the little Board on your picture.

Posted by Paul Adsett (Member # 25) on July 17, 2018, 09:13 AM:

I still think Antoine simply needs to reverse the red and blue wires on the take up motor - it is running in the wrong direction!
I had a similar problem recently on the FRONT spool motor of my GS1200. This happened when I took the motor apart and cleaned all the crap from the rotor and brushes. When I replaced the motor it ran backwards, even though I had not switched the wires around. I had to reverse the wires to get it back to normal.

Posted by Thomas Knappstein (Member # 6134) on July 17, 2018, 11:45 AM:

Hi Paul!
If you open this Motor to clean it and put the back shield 180 Degree back, than + and - will be changed and you must also change red and blue. But he said that his Motor was new.

Posted by Paul Adsett (Member # 25) on July 17, 2018, 03:16 PM:

Thanks for that info Thomas. Reversing the connections to the rear motor is a very simple thing to do, I think it is worth a try for Antoine.

Posted by Thomas Knappstein (Member # 6134) on July 18, 2018, 07:17 AM:

In one of my GS machines the take up and rewinding Speed was very low. I checked the Voltage on the little control Board and it was to low. Than I changed the Rectifier for this on the main Board and everything was all right again. This little Rectfier will go fail over the years too.

Posted by Antoine Orsero (Member # 41) on July 18, 2018, 08:09 AM:

Thank you all for your advice.
I am currently on vacation and I will try everything on my return.
Happy holidays to you all!

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