Film-Tech Forum ARCHIVE: EIKI EX-6100 rewind problem

This is topic EIKI EX-6100 rewind problem in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Christopher Woollard (Member # 2455) on 04-29-2014, 11:54 AM:

I am restoring an EIKI EX-6100 series projector (500W Xenon) which is in generally good condition. The only real problem is that 6000 ft rewinds become very sluggish and slow, only just managing to complete, the rewound film is really not wound tight enough.

The top spool arm is substantial and contains its own torque motor. This has an auxiliary control sensor attached to the motor shaft in what looks like some kind of feedback monitoring arrangement. First 3000 ft or so seem to rewind fine, then torque just cannot be maintained.

There is absolutely no belt slippage.

Might there be a rewind torque adjustment somewhere?

Take-up spool tensions seems fine, via another torque motor.

Posted by Jeff Taylor (Member # 443) on 04-29-2014, 01:58 PM:

You might also post this on 16mmfilmtalk(dot)com. There's a long time Eiki dealer and service expert who takes questions there, as well as providing service and parts. Good luck.

Posted by Peter Hall (Member # 695) on 05-01-2014, 11:28 AM:

Hi
The 3030 / 5000 and 1500 were the same - they shipped from the factory with easy spools on the takeup, but even with these all of the machines we have / have seen slow down to a crawl when rewinding the last few thousand feet
Cheers

Posted by Leo Enticknap (Member # 534) on 05-01-2014, 01:40 PM:

Same thing with the Fumeo 16mm pedestal machines.

To be honest, I wouldn't want to rewind 6k of film on a projector anyway: too much inertia, not enough tension control and a recipe for edge damage and cinching.

Could it be used in conjunction with bench-mounted rewind heads (or even better, given the weight of 6k, a flatbed)? Or is it destined for use in a situation where that's not feasible, e.g. a tiny booth or someone's living room?

Posted by Christopher Woollard (Member # 2455) on 05-02-2014, 12:46 PM:

Thank you everyone
Seems the rewind issue is normal for these projectors
My Cinemeccanica db5 tower does a much better job for 35mm.
Will try and get hold of a bench winder for 16mm.

Posted by Gary A. Hoselton (Member # 3447) on 05-02-2014, 10:21 PM:

Agreed, rewinding on the bench is safer for the film. On the projector, the film path is too long, 16mm film flaps about a bit, and can't really watch what is happening with film moving vertically and typical illumination in a room. The few times I tried rewinding 5000-6000' reel on my EX-6000, speed seemed OK to the end. Perhaps current to your feed arm motor is too low in rewind mode? There is low current in forward mode to provide holdback tension on film.

I think the EX-6100 should have a 1000W lamp rather than 500W.

Posted by Christopher Woollard (Member # 2455) on 05-03-2014, 04:45 AM:

Thank you Gary,
This particular projector was supplied with a very small rectifier capable of 25A max.
A pity as 1K Xenon lamps are much easier to obtain. The lamp house can easily take a larger lamp. If I ever come across a nice switch mode rectifier I may upgrade the lamp.