8mm Forum: Bell & Howell 644

This is topic Bell & Howell 644 - Double Image in forum 16mm Forum at 8mm Forum.

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Posted by Steve Withnell (Member # 5495) on July 28, 2016, 01:14 PM:

I've picked up a B&H 644 off eBay recently and running the projector forward, I get a double image (ie frame in the middle of the screen). I can run the projector backwards and the image is fine. The valve amp / optical pick up works, but the sound is of course distorted.

The Service Manual suggests the shuttle adjustment is off, but I'm not a repair tech, so I don't want to follow the manual blindly, then discover the fault didn't go away. (I know what I don't know, and it's a lot with this piece of kit). I do know the projector was bounced around during shipping, as the lamp was rattling loose in the lamp housing (and yes it did go bang when I applied power..) Any thoughts where I should look first to correct this issue of the double image?

I've also worked out how to make some of the alignment tools, if I could source dimensioned drawings I could probably make most of them - so any links to the drawings would be appreciated.

Best regards

Steve

Posted by Barry Fritz (Member # 1865) on July 28, 2016, 03:42 PM:

I am not familiar with that machine but it must certainly have a frame adjustment lever/knob. Have you tried adjusting it that way?

Posted by Steve Withnell (Member # 5495) on July 28, 2016, 04:25 PM:

Hi Barry,

I think there is a clue there. The Framer control doesn't seem to have much effect on the framing at all. One thing I'm puzzling over, is that the image is fine running in reverse and the framer has little effect. Run the film forward and I get the double image.

Steve

Posted by Maurice Leakey (Member # 916) on July 29, 2016, 02:32 AM:

The 644 is now probably over 50 years old and maybe its lubrication has become thick and sticky.
The framer in normal use has a large range of frame movement.
Is the framer knob turning OK, or does it seem reluctant to turn?

Posted by William Olson (Member # 2083) on July 29, 2016, 09:19 AM:

An observation: I've noticed on any projector I've used that the frame always shifts when running film in reverse. Anyway, could be the frame adjustment control itself is in need of repair. I don't know this machine but if you can visually see how the frame adjustment is supposed to work, maybe you can see the problem and a way to fix it.

Posted by Arturo Glez (Member # 4700) on July 29, 2016, 05:34 PM:

Dear Steve,

Hi, I recently have a "Hell and Bowells" 644 too.

The framer of my machine does not move in any direction seems "immobilized" but on my case, I put a film and the image in the screen appears well without upper or down frammer line. See here:

https://www.youtube.com/watch?v=DeN-a-I_PVQ

I see the framer mechanism is very complicated to see and to work on it.Did you got it repair/move the frammer?

The worm gear in mine machine is little affected, I hope that live a lot of time (only God knows...) See here:

https://www.youtube.com/watch?v=ANxd3nhfR5Y

If you need the service manual Steve,I have it.I can share it with you.

Regards, Arturo.

Posted by Steve Withnell (Member # 5495) on August 07, 2016, 03:27 AM:

Head hung in shame...I used an electronic caliper to message the shuttle throw and it was just about in spec (0.3025inch) with the adjustment range of the framer. I'd bought a few spools of junk 16mm film to practice on, threaded it up and the projector ran fine.

Threaded up the original film and I got multiple images again. Compared the sprocket holes on the junk film to the 'problem' film. Seemed identical, re-threaded the 'problem' film, perfect, decent image decent sound. Ran it again, good image, loads of wow&flutter on sound.

Learning - if you thread the projector properly, it might just run properly!

However, the projector does need a thoroughly good service, so that sounds like a useful task for the cold winter evenings. It definitely needs a good clean, lubricating properly and new belts.

Looking at the amplifier schematic, it's made to have a guitar drive it - must see what that sounds like!

Steve

Posted by Barry Fritz (Member # 1865) on August 07, 2016, 12:41 PM:

Great that you got it figured out. It is not clear to me what you were doing wrong. Regarding the wow and flutter, make certain the film is tight over the sound drum, and mak sure the sound optics are clean and unobstructed. Also, without film threaded, spin the sound drum by hand and let go of it. It should continue to turn on it's own for quit a long time. If it doesn't, it neds cleaning and lube.

Posted by David Guest (Member # 2791) on August 07, 2016, 12:56 PM:

I have a mint one of these for sale

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