Peter Jason wrote:
Epsom R290 inkjet.

The long horizontzl slider bar inside this old old old printer is
never lubricated.

Shoul I oil it with something? It seems to struggling, and it
vibrates alarminly.

Examples of lubricants I stock he

WD40 = too sticky, will attract paper dust and regular dust

3-in-1 oil = too sticky, will attract paper dust and regular dust

paraffin wax in solvent = No (used for bicycle chains)

chainsaw lube = too sticky

silicon lube = spray tin, methylene chloride solvent, spray on paper towel,
wipe over surface, allow to dry thoroughly before power up,
gives a light lubrication, not as good as 3-in-1 from a
mechanical perspective, but a good compromise.
Leaves a film lube, without being excessively sticky.
Must be repeated regularly (3 months?).

graphite = Dry lube, doesn't stay on the work for very long.
Doesn't attract dust, because it's not present long
enough for that.

Since an inkjet can only be clogged by wiping a foreign material
over the heads, it would be pretty difficult to stop inkjet
operation, short of negligence. Whereas with a laser printer,
and the high voltage on charge transfer wire, you might
leave some material in a high voltage section by accident.
An inkjet, relatively speaking, should be more tolerant.

Naturally, never get your lubricant of choice, on any
paper-pickup components or rubber rollers in the paper
path. That's why you don't spray the silicon lube on the
work, but use a paper towel for transfer instead.

Dispose of the paper towel *outside* the house
when you're finished with it. If that was methylene
chloride I was smelling, your body metabolizes
methylene chloride vapor to CO (carbon monoxide).
Usually it takes excessive usage in a confined
space to kill you (an area with zero ventilation,
you vaporize a *lot* of solvent, you stay in the area
for a few hours).

(Sample/background info)

https://en.wikipedia.org/wiki/Jig-A-Loo

They indicate there are a couple of solvent choices
for the stuff, neither of which is very nice.

Paul