Lubrication?

[Thomas Dafnides]

The film pull down Claw at the aperature gate on a projector is attached to an arm that ends with contact to a type of hexagon shaped nut that gives it its intermittent movement. My question is what is the best lubricant to put on this nut where it contacts the arm ? Grease or oil?

[Alexander Vandeputte]

Generally speaking, as a rule of thumb (although there may be some exceptions) you only use grease in most super 8 and 16mm machines as oil will wander around or splatter and eventually will wind up on your film. But more knowledgeable people can elaborate further.