I've been rebuilding a second hand gantry plasma table that uses rack and pinion drive and HiWin rails and sliders. I notice looking at the HiWin literature that the sliders are fitted with 6 mm threaded holes for grease nipples, but the holes on my sliders are fitted with blanking plugs.

Should one grease these things on a plasma table, or will all the grime just stick to it. I can see the argument that a pump of grease pushes muck out of the assembly - it's the same argument on earth moving equipment - but what is the consensus - to grease or not to grease?

I'd very much welcome your views.