This is topic B&H 2580A Video of Issue I'm Having in forum 16mm Forum at 8mm Forum.

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Posted by Brad Kimball (Member # 5) on August 13, 2017, 12:04 PM:

What's causing the bottom loop to keep growing outward like that? Yes, the main worm gear has a little crack, but the unit still plays great other than this loop issue.

[ August 13, 2017, 08:29 PM: Message edited by: Brad Kimball ]
Posted by Maurice Leakey (Member # 916) on August 14, 2017, 02:31 AM:

The Bell & Howell Slot Loader differs from the auto-thread model inasmuch as the sprockets are not in line. There is an extra gear called the Lower Sprocket Drive Gear.

If, as you say, the main worm gear has a little crack in it there may be a problem for it to drive the smaller gear. Thus, the sprocket is not turning as it should which results in the claw feeding the film out into a large loop.

Once a main worm develops a crack it will get bigger and bigger. The only answer is to now nip it in the bud and have it replaced. At the same time the engineer can examine the other gear which I referred to.
Posted by Jose Artiles (Member # 471) on August 27, 2017, 01:40 PM:
Here is the part you need
Posted by Brad Kimball (Member # 5) on August 28, 2017, 11:10 AM:
Thank you. Just wondering if it truly is worth the expense to fix both the main worm gear AND the lower sprocket gear. This kind of overhaul will probably cost as much as simply buying a refurbished projector. Six of one - half dozen of the other. There are resources like Richard Patchett to whom this kind of work is a stroll in the park, but it's got to be very labor-intensive. His website clearly indicates that gear replacements are no easy task.
Posted by Andrew Woodcock (Member # 3260) on August 28, 2017, 11:19 AM:
If you get a completely reliable non scratching machine at the end of the expenditure which you can enjoy for many many years to come, then to me, it's a worthwhile exercise.

Just because another machine is cheap, doesn't make it any the better than one with an original damaged worm gear.

You may as well spend the money and finish up with one decent expensive reliable machine rather than own two or three cheap shoddy performing ones with or prone to faults and that are completely unreliable.

That's my own personal take on these things anyhow, despite seeing countless examples of the exact opposite philosophy here and elsewhere.

Buy cheap, buy twice.
Posted by Richard C Patchett (Member # 974) on August 28, 2017, 04:38 PM:
Once again Brad
I Have theses on my web site (NEW)
Posted by Maurice Leakey (Member # 916) on August 29, 2017, 02:20 AM:
I agree with Andrew.
Have the projector overhauled with new worm, small gear, and anything else that is needed. You will then have a superb projector for many years to come.
My 1680G (Bell & Howell Slot Loader) had this problem with threading and the small gear was found to be at fault.

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