Take Up Spool Spinning Too Fast On Bolex 8mm K1

[Finn Benischek]

Hello, 

Yesterday I just purchased a Bolex 8mm Reflex k1 camera. Motor seemed to be running perfectly and smoothly when I tested it. I put some test film into the camera when I got home, ran smoothly for a few second by then jammed up. I've identified the problem as being the take-up spool. It seems to be running faster than the rest of the camera, but just very slightly faster. The claw can't quite keep up with the amount of film being pulled by the spool and it gets too tight and ultimately stops moving altogether. The lower the frame rate, the longer it takes for the film to get too tight. At 12 fps i can run it for about 20 seconds, at 40 fps I can run it for about 2 seconds. Another reason I have identified the take-up spool as the problem is that when I run the film loosely through the camera (not into the take-up spool, just letting it go everywhere) it runs perfectly smoothly at all frame rates. It is only when the film goes onto the take up spool that the jam occurs. 

Any solutions to this problem?

Thanks,

Finn

[Dom Jaeger]

The take-up spool should spin faster than the film going through the gate, but it should slip to keep taking up film without pulling on it too hard. 
If you run the camera and hold the take up spindle you should be able to stop it turning fairly easily. If it is hard to make it slip, the clutch assembly inside needs to be serviced. Often this assembly is just friction between two plates, so it may just need fresh grease.

[Simon Wyss]

On 9/4/2023 at 11:04 PM, Finn Benischek said:

Yesterday I just purchased a Bolex 8mm Reflex k1 camera.

That’s today’s plot. The camera most likely never saw a service since 1962. It takes an investment now for future use. You don’t expect a car that old to roll out of a barn just like that, do you?

The K, by the way, stands for Kern & Co., Aarau, an optical company.