8mm Forum: B&H rewind problem

This is topic B&H rewind problem in forum 16mm Forum at 8mm Forum.

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Posted by Terry Sills (Member # 3309) on December 19, 2013, 12:10 PM:

Hoping that someone can help me with this one. I've got a B&H 1680 slotload in very good condition but I am having problems with the rewind. Anyone familiar with these will know that it is necessary to raise the rear spool arm and then turn the motor to reverse position for rewinding, but the spool does not turn. However if you leave the rear arm down in the project position and switch to reverse it works ok. While it it is in this mode if you then raise the rear arm it rewinds fine. Has anyone encountered this problem? On the 1698 that I have there is a knob on top which you depress to rewind but on the 1680 there is only a framing knob. Is there something I am not doing right?

Posted by Brian Stearns (Member # 3792) on December 19, 2013, 08:09 PM:

Has the belt been replaced since purchsed? Did you open up the back and see if anything is loose like gears?

If you need parts and advice go to

http://www.rcsclassic16mm.com/

Richard helped me with my 1585

Posted by Jim Schrader (Member # 9) on December 19, 2013, 09:03 PM:

have you tried it with load lever in another position?

Posted by Terry Sills (Member # 3309) on December 20, 2013, 05:14 AM:

I've looked in the back - nothing obviously wrong and I've tried the load lever in both positions. Hoping that Richard can help.

Posted by Terry Sills (Member # 3309) on December 20, 2013, 08:07 AM:

Tried it again today and would you believe it - it's working perfectly!
So I've given it a damn good thrashing and made it quite clear that if it happens again it's up for adoption.
Sorry to waste your time folks.

Posted by Terry Sills (Member # 3309) on December 26, 2013, 03:45 PM:

Well it seems the problem persists! I can see what the problem is now but don't know how to fix it. When the rear arm is raised to the rewind position and the switch is moved to rewind/reverse the idle cog is not engaging to the rewind cog. But when the rear arm is in the project (lower) position, it engages perfectly in the reverse project mode. Any ideas anyone?

Posted by Maurice Leakey (Member # 916) on January 01, 2014, 05:26 AM:

Terry

Have you got a TQIII which you can compare with your slot-loader with their backs off? The raising of the rear arm on the latter performs the same action as pressing down on the rewind button on the TQIII, i.e., it brings the fast rewind section into action, although I believe the slot-loader may have a more simple action.

As you know, I am not a technical man, so I cannot go into details as I don't really know much about the "innards" of a projector, but I hope my comment may be of some help.

Posted by Ken Finch (Member # 2768) on January 01, 2014, 06:54 AM:

Terry, I find the mechanics and electronics of all the self threading and slot loading machines extremely complicated and temporamental. Many are almost impossible to do a D.I.Y repair.
If it projects o.k. rather than fiddle around trying to rewind the films on the projector, why not rewind them by hand and save yourself a lot of hassle? Ken Finch.

Posted by Terry Sills (Member # 3309) on January 01, 2014, 01:21 PM:

Maurice
Yes I have compared the 1680 with my 1698 but although mechanically similar it doesn't help solve the problem of why the idle cog will not fully engage with the rewind cog.. I did remove some old solidified grease and regreased the idle cog but to no avail.
Ken
I think you are right. Why bother. It's always best to use proper rewinds anyway. It's just that I like to have things working properly if possible.
Thank you both.

Posted by Maurice Leakey (Member # 916) on January 11, 2014, 03:17 PM:

I believe that the two projectors mentioned do not have exactly the same rewind gears, it is possible that a previous owner of the slot loader replaced gear/s of the incorrect size.

Also, the operating mechanism for the rewind system differs between the two.

But, as already said, it's just as quick to use a manual rewind. Whilst I usually rewind on my Super 8 projectors, I never do this with 16mm, mainly because they don't take up neatly which I can do by hand very easily.

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