A lot depends where the oil can be introduced to the ways, anything will help, though as oil will be dragged along as movement takes place. There are probably as many different ways to do the grooving as there are people doing the grooving and all will help. If you can clamp a guide for the grinder to follow it would give straighter grooves,or just follow a pre marked pattern.

Taf, your ideas are more-or-less sound, providing you can control the die-grinder (I know I couldn't, so would have to set up some sort of guidance fence, template, whatever).

There's a typically excellent YouTube video by Stefan Gotteswinter, some time ago, in which he discusses the desirable features of oil grooves, particularly the desirable shape of the arris at the transition from groove to guidance surface. (You don't want the groove to act as a scraper.)

Not sure about Tug's suggestion. I'd have thought that when the table picks up some oil, the saddle's groove's oil level drops, so no more chance of pick-up by the table. Perhaps a sump and wick might work? Having the grooves in the upper surface is like having oil-retaining scraped features preferentially in the upper surface: they don't accumulate potentially abrasive gunge. Also, the resevoir of oil in the groove and its supply channel feeds until it's empty. Sure, oil dribbles out from the exposed grooves, where the table overhangs the saddle, but that's a reason to have the table's groove system broken up into shorter lengths, with individual supplies.

On my X45 mill, I put the grooves into the cross block, and made them with a ball mill cutter. While at it, made a side mounted single point to lube both sides of the X axis and the Y axis. I just followed what other mills I have used that have lasted a long time have used. I also added an oil area to get oil in the gib on the sliding side, instead of relying on just what ever dripped from somewhere. I have some pictures in my album of what I did to the X45mill . My view is grooving all the table length does is drips oil onto the floor.

Now instead of pumping oil through, I am now pumping the grease from DMG Moori , 000 grease. Quite an amazing product, and it keeps lubricating for longer. It can also allow for smaller gaps and not seize as well. It goes through the oil gun just great, like oil but is a very light grease. It is whitish in colour.

Neil

The one shot lubrication is also a potential issue with DRO as well as reduced travel. Suggest rebuild and observe carefully where everyhing needs to go as you may find location and clearance issues.

Robert Butler

Zig-zag or S-pattern will work just fine just don't make the grooves straight along the way or you'll have problems when it starts to wear.

Having the grooves in the non-moving part is also a good idea, I have a slotting head I just rebuilt from chronic lube failure because they put the oil grooves in the slide, and they extend past the bottom of the fixed ways. To compound the issue they put the feed hole half way up the slide so the oil purs out the bottom but doesn't make it to the top.