8mm Forum: Keystone 109D - Master Switch problem

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Posted by Chris Smart (Member # 7022) on July 10, 2019, 12:52 PM:

Hello!

It seems my projector has an issue with the master switch. I need to wiggle the switch a little closer to 'Lamp' from 'Motor' to get the motor to start. I suspect the contact is worn or misaligned. Has anyone else had this issue with the master switch and is there a way to fix it?

Posted by Steve Klare (Member # 12) on July 10, 2019, 03:39 PM:

Hi Chris,

I don't know these machines very well, but among the ones I do know, the "switch" isn't a switch, but a system of switches. The knob twists a camshaft, and the lobes on the cam depress switches to turn lamps and motors on and off, forward and reverse.

Can you access whatever is behind that knob and take a look?

In an ideal Universe your knob would be on there wrong (or the wrong knob) and the fix could be simple.

(In my experience the Universe can stand some improvement...)

Posted by Chris Smart (Member # 7022) on July 11, 2019, 06:02 PM:

Thanks for the reply Steve!

I can only get a glimpse behind the switch when i open up he splicer drawer found below it. Looks like I will have to remove the projector from the base and then remove the bottom plate (if possible) to gain full access to the back of the switch. The switch seems to be getting worse. It struggles at low speed but now I have to really play with the position to get it to start at all. And when i move to the lamp theres a delay like the motor switches off and then on again.

I'll open it up and take some pictures of the connections when I get a chance. Hope I can fix it!

Posted by Chris Smart (Member # 7022) on July 30, 2019, 09:57 AM:

I have good news! After removing the base and taking a look inside I discovered the top line connected to the main switch from the Pilot Light became completely disconnected after I removed the main switch screws. The screw is threaded and the area had evidence of arcing. It was clearly just floating there.

Since the screw was no longer usable I had to find a replacement. No success at Home Depot or other hardware stores. I tried a 4 diameter and a 6 diameter screw, all too small or too big. Turns out its a a hard to find and rarely used 5-40 machine screw. I was lucky and found a fastener shop in a nearby industrial area, even they said it's a rare size.

I cleaned up the area, assembled it back together and it runs perfectly. Here are some images

Posted by Steve Klare (Member # 12) on July 30, 2019, 10:00 AM:

"5-40"???

That's a new one on me!

Then again there are (were?) "B" Cell batteries!

Nice Work!

That's the joy of something like this, they are so simple that they are often understandable and fixable. I got an Epson video projector about two years ago. When it breaks I'll probably just bury it out in the yard!

Posted by Chris Smart (Member # 7022) on July 30, 2019, 10:43 AM:

It was a good feeling when I flipped that switch after fixing it! I also found a tiny piece of cut film inside, maybe 3 frames. At first I thought it was just burnt with now images but i used the viewer over the pilot light and i was surprised to see an image of two individuals in a room with some cats. So much fun.

Posted by Leon Norris (Member # 3151) on July 30, 2019, 10:55 AM:

Enjoy the films!

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