PDP-11/34 cable trouble

[thunter0512]

I am making a second start on restoring a PDP-11/34 found in a barn.

Some time ago I already removed the power supply assembly in the back and disconnected the many cables going from the power supply to the main chassis.
The cables were extremely stiff as if the cable insulation had lost all of its plasticizer.

The two components became more manageable for one person rather than having it as a single heavy unit.

Using compressed air I blew out a lot of dust, decayed foam and dead bugs.
I also wiped over all external surfaces with a moist cloth to remove decades of dust and grime.
After everything was completely dry I wrapped it all up and packed it away waiting for spare time to start restoring it.

Today I unpacked the 11/34 and did a more thorough inspection.
I remembered the stiff cables and tried to reconnect a few of them just to find it near impossible.

Here are a few questions I hope somebody can answer:

• What is the plastic cable insulation made of?
• Is there anything I could apply to the cables to soften them without causing damage to the insulating material?
• Is there any way to introduce fresh plasticizer to the cable insulation?

In another thread somebody suggested to use a hairdryer to warm up the cables to make them more pliable, but of course as soon as the cables cool down again they will be as stiff as before.

The old connectors with nylon bodies are hard to work with too, but contact spray seems to make it a little easier to connect/dis-connect them.

Thanks
Tom

 

[Alegend]

Hi Tom, I asked a friend who does plastics for a living for many years.
He said if such a material existed that restored flexibility to old PVC, he'd use it on his elbows.

The plastics have gone through molecular-level degradation, so new wiring is probably your only hope if you want the luxury of flexible wires.
-Alon.