8mm Forum: Bell and Howell 2580 Issue

This is topic Bell and Howell 2580 Issue in forum 16mm Forum at 8mm Forum.

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Posted by Peter Gilabert (Member # 5948) on May 22, 2018, 03:38 PM:

Hey Follks,
Anyone have an idea of what might be going on if the sound is goiing in and out on my B&H 2580? Everything else seems ok and if I tap that loop former and hold it down the sound comes back out of course the picture is messed up then.
My instinct is that the film is somehow too far from the sound roller drum.
The worm gear may have some hairline cracks and it is a little loud/ clackity but otherwise perfect.
I’m up for replacing the worm myself but I wonder if someone thinks it’s a smaller problem?
Thanks in advance,
You fellow projector nerd Peter

Posted by Nantawat Kittiwarakul (Member # 6050) on May 22, 2018, 09:09 PM:

A slot-loader ones right?

Never use this particular model before,but I guess there'a a lay on roller to keep the film in firm contact with the sound drum. This roller would raise up during threading,and closed down when running. It might half-stuck in between the positions hence the garbled sound.

Posted by Maurice Leakey (Member # 916) on May 23, 2018, 04:51 AM:

Peter

From what you say it's quite possible that your faulty worm maybe the cause of your trouble.
Have a read of an earlier posting on a similar subject which also refers to the offset gear.

http://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=5;t=001662#000001

Posted by Peter Gilabert (Member # 5948) on May 23, 2018, 08:54 AM:

Thanks for both your replies,
The lower loop isn’t increasing in size as mentioned in the earlier post. Of course a tiny crack may still be causing all this, but I’ve seen the manual now and have read about a few adjustments I can try, which Ideally require special tools to set screws so that the film lines up perfectly with the sound drum and a couple of other troubleshooting things I can try.
I think something is causing the film to be just a little too far from the sound drum.
Well I’ll investigate all these possibilities ASAP.

Posted by Nantawat Kittiwarakul (Member # 6050) on May 23, 2018, 09:48 PM:

Try running with the cover off to see if anything stuck there. Then try manually press the pinch roller down when running to assure firm contact between sound drum+film+pinch roller. See if that make any improvement then.

Posted by Peter Gilabert (Member # 5948) on May 27, 2018, 05:55 PM:

So this is what it sounds like: I usually get a sound but it’s distorted and sounds like someone talking in a car driving a thousand bumps in the road!
Maybe it is the worm gear after all but here’s the link:
https://vimeo.com/272126607

Additional theories?

Posted by Jim Schrader (Member # 9) on May 28, 2018, 08:44 AM:

have you tried resetting the loop? to see if that corrects it momentarily? the worm gear requires all the bells and whistles to be put back in with guages otherwise it may not operate correct or at all.

Posted by Peter Gilabert (Member # 5948) on May 28, 2018, 09:37 AM:

Hi,
Yes, I’ve played with the loop reset plenty.
There are a few issues going on. The speed now starts out slow and builds to normal when I play a reel. I’m guessing I may need just a new motor belt for that, it looks and feels fairly loose.
Secondly, as you can hear from my video posted above, the sound is usually working, it’s just “jittery” sounding and distorted, like when you drive on a bumpy road and talk.
According to the manual, it could be all sorts of fun problems.

Posted by Richard C Patchett (Member # 974) on May 28, 2018, 10:45 AM:

Greetings Peter
I have the belt in stock There on my web site
709679 Motor Belt $15.00
For the 1500 - 2500 Series

Posted by Peter Gilabert (Member # 5948) on June 07, 2018, 08:01 AM:

Thanks Richard,
I’d already ordered one from Urbanski.
So I feel like both a GENIUS and AN IDIOT!
I patiently waited in the mail for some Bristol wrenches, opened the projector up, changed/replaces the motor drive belt all by myself, then turned on the projector to- nothing- dead.
I was obsessed with the plug and cord and the idea of replacing and testing all those devices when I realized it was left in Position 1!
So I pushed it back, turned it on and had good speed.
Then I remembered, I still have my sound in/out problem.
I went to the manual, looked at the area there again, and as I was cleaning it up I realized that I never thread the film under that little metal clip that holds it to the sound drum!! Can you say Duh?
Duh.
Projector works great, just gotta make the sound a little smoother... 😃

Posted by Maurice Leakey (Member # 916) on June 07, 2018, 10:46 AM:

quote:
I never thread the film under that little metal clip that holds it to the sound drum

What? It's a slot loader, so easy to thread. Have you been trying to load the film without the cover on?

Posted by Peter Gilabert (Member # 5948) on June 07, 2018, 10:53 AM:

Hi Maurice,
I’ve had no problem threads by the film, I just never noticed one tiny thing: that the film runs under that little metal wire over the sound drum...much better now.

Posted by Peter Gilabert (Member # 5948) on June 17, 2018, 10:44 AM:

Actually,
Nantawat nailed it the first time. After reading the service manual a bunch of times, I suddenly realized the pinch roller wasn’t even resting against the sound drum when in run mode.
It looks like the spring isn’t really pushing it there, though strangely enough if I push it, it stays.
I may be able to live with this, or remove and fix the spring.
The sound is so much better now.
Thanks for the input.

Posted by Nantawat Kittiwarakul (Member # 6050) on June 18, 2018, 12:01 AM:

Gotcha! [Big Grin]

It's very possible that the roller's pivot might just freeze up,due to the lack of lubricant (after 30 years,that's ok then). It would then get "stuck" in up position,needing your assistance to push it down when running. Adding a drop of oil at proper point should help freeing it up then.

Posted by Peter Gilabert (Member # 5948) on June 18, 2018, 04:37 PM:

Hey Nantawat,
I know that grease people use for these projectors but do you or anyone recommend any type of oil I could use for that part?

Posted by Nantawat Kittiwarakul (Member # 6050) on June 18, 2018, 10:50 PM:

Since it isn't the high load bearing/very stressed pivot,any lightweight machine oil should do. (Thinking about sewing machine oil.)
Besides,could you provide the closeup shot around that sound drum/pinch roller area? I might help pinpoint where it should (and should NOT!) be oiled. [Wink]

Posted by Peter Gilabert (Member # 5948) on June 18, 2018, 11:59 PM:

Nantawat, here are some close ups:
/Users/petergilabert/Downloads/IMG_4652.jpg/Users/petergilabert/Downloads/IMG_4662.jpg/Users/petergilabert/Downloads/IMG_4664.jpg

Posted by Peter Gilabert (Member # 5948) on June 19, 2018, 12:00 AM:

Ok, trying again!

and with it down against the roller

from closer:

Posted by Nantawat Kittiwarakul (Member # 6050) on June 20, 2018, 12:03 AM:

That's it. [Big Grin]

It's very likely that this pivot is spring-loaded,with the linkage on the left to lift it to the "up" position when threading. When in "run" position,the linkage will release and let it drop down by the spring force behind it. You should be able to lift it up with finger and feel the spring resistance. If it stays in the "up" position,then lube the pivot as the picture.

Caution - NEVER MESS WITH THAT NUT! that is used to adjust the film's lateral position around the sound drum.
If it's out of position...I can only wish you good luck then. [Eek!]

Posted by Peter Gilabert (Member # 5948) on June 20, 2018, 05:41 AM:

Nantawat,
So I put oil there and it took a little while then I kept wiggling it- then it worked! Snaps back fine! Thank you for your advice! Now I just need to increase the torque on my rewind clutch gear...😉

[ June 20, 2018, 07:57 AM: Message edited by: Peter Gilabert ]

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