Century framing lamp cord replacement

[Scott Norwood]

I've run into a number of Century projectors where the rubber insulation on the framing lamp power cord has started to deteriorate. Is there a straightforward way to replace the whole cord? How does the plastic grommet thing that secures the cord when it enters the projector head work?

[Sean McKinnon]

It's usually a Hubbell "Midget" twist lock HBL7464V is the cable end I believe. You probable want to replace it with the grounded version.

[Tony Bandiera Jr]

IIRC Century just used standard "zip" style lamp cord for the framing lamp. And also IIRC the connector has two screws on a flange you can remove to get to the connections. The socket end is tricky, I think it was molded in, so you'll need to replace the whole socket and cord as a unit. Which will be difficult to find and costly. (That Hubbell connector is stupid expensive.)

My suggestion? Replace the whole mess with a 12v DC LED lamp assembly and 12v DC Power supply. Safer, and will last virtually forever. And no more shock hazard. The framing lamp is just for backlighting the hole, so nothing fancy optically is needed.

One of my chains back in my service days did just that (using incandescent 12v lamps) to save on relamping and enhance safety (they had experienced a few 120v "blowups" when the cord wore out and shorted to the projector.)

[Tj Hopland]

The Hubbel plugs are a brown color and have a grooved texture to them. If that is what you have just yank and they will come out. They are straight blade, not twist lock. Once its out if you look at it and you will see near the end its smooth, that is the main body and the grooved/textured part is a threaded on cover. Once the cover its off there are screw terminals so its fairly easy to install a new cord. They can be pretty brittle so be careful if you grab the smooth part with something like a pliers to try and unscrew it. A possible method of holding it would be to plug it back in and let the socket hold it while you turn the cover. Either way take it easy especially at this age.

When we had any issues with them at all including the plug just missing on a used head we would convert them to low voltage. 12v bulbs were easy to source and safer for those working around em. Strong would supply them with a hardwire transformer similar to a Simplex and those machines they replaced the incoming power socket with a big plug that had a typical strain relief thing in it. I believe they even sold that in a retrofit kit.

At the time there were universal battery adapter power supplies available that had a little voltage slide switch from 3-12v and a multi tip end. You could just cut the tip end off and crimp on a couple fully insulated 'quick connect' terminals. Those would fit the blades in the Hubbel socket tight enough to hold just fine and the voltage switch acted like a dimmer so you could set it at a voltage that gave you enough brightness to do the job but gave better lamp life.

At 12v (or less) if the cord made it into the flywheel or anything else went wrong no big deal. This got a little more exciting at 120v on a 15 or 20 amp circuit. i remember one site where it was lightly rubbing on the motor flywheel and no on noticed (or got shocked). I was doing a PM call and noticed the motor bearings were really really bad which wasn't a common problem with that brand of motor. Turns out that the power from the damaged cord was finding a path to ground through the motor bearings but between the lube in the bearings and the brush action on the flywheel wasn't blowing any fuses or breakers. Didn't do the bearings much good tho.....

[Scott Norwood]

Thanks, all. It sounds like converting to 12vdc would be the best and safest option.