8mm Forum: Sankyo 2000H

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Posted by Terry Sills (Member # 3309) on April 09, 2013, 05:07 PM:

I have just acquired a Sankyo 200H in very nice condition but the rubber drive rollers work intermittently so that while viewing a film it will suddenly stop. Does anyone have suggestions of what the cause may be? Is there any adjustment for the roller drive mechanism? Would be a shame to dump such a nice machine.

Posted by Barry Webb (Member # 1897) on April 09, 2013, 06:48 PM:

Hi is the motor drive belt ok and not slipping, These machine's are fantastic don't scrap it.

Posted by Terry Sills (Member # 3309) on April 10, 2013, 05:05 PM:

Hi Barry - The belt has been replaced and I don't think that is the problem. As you know they employ rubber rollers instead of sprockets. They are not turning as they should but when you put a little inward pressure on them they do. That is why I'm wondering if there is some adjustment to the drive mech of these rollers
Terry

Posted by Barry Fritz (Member # 1865) on April 10, 2013, 05:19 PM:

Calling Dr. Frank. Hopefully he will see your post and reply.

Posted by frank arnstein (Member # 330) on April 10, 2013, 09:01 PM:

Hi to Terry, the 2 Barrys and others reading this thread.

The annoying symptom as described above is quite common on Sankyo 1000, 1000h and 2000h dualux projectors. Especially if they have been unused for some time.

The drive to the roller is by means of a one way dog-clutch. This dog-clutch is spring loaded using a very fine spring that pushes the 2 halves of the clutch together. They lock up and provide drive to the rubber roller in forward project mode. When reverse is selected the dog-clutch will disengage itself automatically. The fine compression spring collapses to allow the 2 clutch halves to slide apart and so interrupts drive to the roller.

This symptom is the direct result of hardening of the grease which normally helps the 2 clutch halves to slide apart. Solidified grease will prevent the automatic coupling and decoupling of the drive to the roller.

The cure is to clean and lubricate the sliding, spring loaded inner clutch-half so it slides on its guide again.

This is easy to do once you remove a few screws on the outside to allow access these pieces. Once they are exposed, spray them with evaporative cleaner and then re-grease. Manually slide the parts till they are free again, allowing the inner clutch half to slide out freely and couple up the drive to the roller.

So good luck with fixing your Sankyo as they are a great machine.
Let us know how you go.

dogtor frankarnstein

Good luck with

[Smile]

Posted by Barry Fritz (Member # 1865) on April 10, 2013, 10:22 PM:

If anyone does this, pics of the process would be very much appreciated!

Posted by Pete Richards (Member # 2203) on April 10, 2013, 10:41 PM:

I'll be attempting mine tonight, I'll try and grab some photos of the process.

Posted by Terry Sills (Member # 3309) on April 13, 2013, 01:42 AM:

Dr Frank - You're a genius. Thanks very much for that info. I will get onto that and let you know.

Posted by Terry Sills (Member # 3309) on April 13, 2013, 06:14 AM:

Calling Dr Frank - I have done as you describe and Hey Presto! you were right. However, another thing that I can't work out is that the pull-out rewind control doesn't seem to do anything. With the knob pulled out the rubber roller is disengaged as it should be but the rewind is no faster than if you do not pull out the knob. Not a major problem as the rewind seems fast enough anyway. Just wondered why. Another thing I have noticed which seems symptomatic with these machines is that when running damaged film, with missing sprocket perforations, the film will stop and if you are not careful, a burnt frame results. Am I right in thinking that this is because there is no take-up roller to pull the film through, as with other projectors, and that the only take-up tension is provided by the take-up reel which is insufficient to pull the damaged film past the gate claw?

Posted by frank arnstein (Member # 330) on April 13, 2013, 06:51 AM:

Hi Terry

Glad you were able to follow those rambling instructions and have been successful in fixing your Sankyo threading.

As for the rewind lever and how it works.
You have discovered that it will rewind with the lever in or out.
Thats normal. However when its pulled out, a positive lock engages to prevent any slip during rewind of heavy full reels. The rewind speed will remain the same but if you try to slow the reel down with your hand you will feel that its locked and wont slip. Push the lever back in and it will rewind but it can then be slowed down by hand because its not locked positively.
Always remember to push the knob in after rewinding film.

If the film has a faulty sprocket hole then it will stop advancing and could burn a frame if you don't nudge the take up reel to get it going again. This is normal too, as there are no sprockets to tractor the film through the machine. The claw does all the work assisted by the rubber threading roller which feeds film in to the gate.

dogtor frankarnstein

[Wink]

Posted by Terry Sills (Member # 3309) on April 13, 2013, 01:00 PM:

Thanks again Dr Frank - What would we mere mortals do without you?

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