Keystone K-75 8mm

[David L. Baker]

Are there forum members using a Keystone K-75 projector with their 8mm films? I have this model, and like using it, as this seems easy on the film, and has manual threading. These projectors were made in Boston Ma in the early 1960's. Similar Keystone models are the K-62 and K-65. If you have experience to share, please add a reply to this post. I am NOT interested in buying or selling anything. My post is about information. Thank you in advance.

[Don Elsass]

I don't have your model but recently someone gave me a Keystone 98z 8mm projector. I want to check the belt but I can't remove the rear cover. Also looking for a free user manual.

[Dean Gallea]

I have a K-67 autoload with a little glitch in that the supply reel unwinds by itself. Apparently, the spring clutch that drives the spindle in rewind is not fully releasing in forward, so there's enough coupling that the reel unwinds. I know the lower spindle has a small bracket under it that catches the spring clutch preventing it from engaging in rewind, but there's nothing like that on the supply spindle. Any insights? How can prevent forward torque from turning the spindle?

[Dean Gallea]

I've tried to figure out the logic of my Keystone K-67's reel-drive belts. It appears that the take up spindle is clutched directly to a steel-coil belt off the main drive gear, and in order to turn slowly during forward take-up, has to slip the steel belt on its pulleys. Can that be the way it's designed? I would really like to see a service manual to learn if it's assembled as designed.

[Brian Fretwell]

That certainly is how my first (toy grade) cine projector did it. I wouldn't be surprised if others used that method too for cost reasons.

[Dean Gallea]

Brian, the problem I have is that the feed spindle, which has a coil-spring one-way clutch to decouple it from the turning shaft inside, isn't sufficiently decoupled to prevent it from turning anyway and unspooling the film. There doesn't seem to be any mechanism to provide "drag" to allow the spring clutch to slip. Weird. Makes me want to buy another used one to see how it's supposed to work.

[Dean Gallea]

I give up on figuring out how the take-up clutch is supposed to work. I'm offering this otherwise-working projector to anyone who wants it for either repair or parts, just for my shipping cost. Let me know if you'd like it - before December 2023, or I'll trash it.