Lubricating Speed Graphic Shutter Trip Cable?

[F4U]

It seems to me I might have known and performed lubrication of some kind long ago on the cable that leads from the shutter trip release on the Kalart side of the body. I have 2 speeds I want to put into use, but those press buttons are stiff, and I believe the cable itself is the source of the problem. Not being a complete dunce as to getting out an oil can, surely there s a properly prescribed procedure? Thank you.

 

[juan]

Anything related to Graflex cameras, search here for posts by @shutterfinger. He was the expert. Unfortunately, his eyesight failed a couple of years ago, so he no longer posts.