8mm Forum: Please Help w/Bolex 18-5 problem

This is topic Please Help w/Bolex 18-5 problem in forum 8mm Forum at 8mm Forum.

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Posted by Rick Fisch (Member # 4985) on August 01, 2015, 09:57 AM:

The take up reel on my 18-5 started jamming during normal forward play (reverse works fine). I see that the small silver metal bar protruding from the side of the gear (circled in red in the 1st pic) is hitting the black tab attached to the axle (circled in green) when playing forward. It clears it when playing in reverse. Is this normal or the source of my problem ? If it is normal, something deeper in the bowels of the Bolex must be at fault. Any insight and advice will be appreciated, including the proper name of these parts.

Just to clarify, when I say jamming, the take-up reel wants to pull TOO HARD on the film it is taking up, accompanied by an unpleasant groaning. Upon opening the projector, the chain between the two reels is way too tight on the bottom span. Reversing the projector immediately "loosens" things up.

The silver tab swivels about 15 degrees ... is this part of the normal design or has my plastic gear gotten gouged ?

Many thanks in advance to anyone responding with info.

Posted by Barry Fritz (Member # 1865) on August 01, 2015, 10:34 AM:

Hi Rick. Welcome to the forum. The action you describe is appropriate. The tab engages the black thing on forward and disengages it on reverse. Your problem is elsewhere. It sounds as though the take-up is turning faster that what the film can move through the sprockets and gate. Make certain the the sprockets are turning freely and that the gate is clean. Some lubrication may be in order. Do you have the same problem running at 5fps?

Posted by Rick Fisch (Member # 4985) on August 01, 2015, 11:49 AM:

Thanks for the welcome and quick reply Barry. Yes it happens at 5 fps too (actually, it binds up so quickly the problem is evident before I even get to move the knob past 5).

I've owned the projector for about 15 years and I put new belts and lubed what I thought was safe to lube about a year ago and it was running great. Last night I was about an hour into a medium size film transfer project and it bound up in the middle of a reel. With no take-up reel on, it is still running fine and the movement of the take-up spindle seems appropriate (tho I never paid close attention to it before so I can't be sure). With film and reel on, it seems like the take-up reel is spinning too fast/strong.

When I removed the back cover, I didn't see/hear anything foreign that would interfere with the chain but its hard to tell with that transformer in the way (doesn't look fun to remove). So I am now wondering if it could it be something in the transmission ? Writing this it now seems more likely to me to be whatever lurks inside the arm that swivels and holds the reel.

I've got to get this project done so I will probably set up some kind of off-projector manual wind take-up reel to get me through it and have a closer look at the inside of that arm when time permits.

Thanks again!

- Rick

Added: Re-reading your reply, I just thought I should also mention that the film does move through all the mechanisims before the take-up reel at the correct speed (or reasonably close). It sure seems like something that should be slipping isn't (leads me back to that arm).

Also, I just remembered I did make one change before this project ... I moved the voltage from 110 to 117 to better match what I measure from my outlet (115). I can't imagine that would make any difference but I will move it back to see.

Posted by Barry Fritz (Member # 1865) on August 01, 2015, 04:15 PM:

You have answered some of my thoughts. If it is moving through the sprockets and film gate like it should, it is likely a problem with the take-up spindle. You can take the cover off the reel arm and check the gears in there although I can't imagine what might go wrong in there besides lubrication. Set the projector on its back when you unscrew and remove the arm cover so the gears don't spill out. These are very reliable, well built, simple machines and I have not heard of another having a problem like yours. Usually the problem people have with them is in the switch. Good luck with your project and if you discover the problem, get back to us and let us know what it was.

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