Rick,

With that ballnut a good bit of the issue with lubrication is mute BUT still make sure you have access. I also see why you want to keep in near completely enclosed as that nut does not have protective flanges for the ball races. Therefore the less chance for swarf to get in the better.

Speaking from experience of a a design done with Jazz and he built for me and I have worked on a good bit and have had to lube and put shims back and all the fun that goes with it, listen to Jazz. Now hear is where I get to make a point a bit clearer. Lubrication is not just the ball nut. Those linear rail carriages are going to want a greasing once a quarter if you are using that machine with a daily use level (that is even with the protective scrapers).

Personally for myself I am setting up a bit of over kill as I am designing a lube system for my current machine that will be a lube block for X, one for Y and most of Z and a single lube point out the front of the Z plate with a cap for the ball nut.

Registers made setting up my machine take two days instead of a week ( even though it came up here in two heavy large sections it still needed squaring, truing and tramming. A side note to folks, tramming is something you should check once a fortnight to once a month (depending on how heavy your use is and what your cutting). My source for this information is a few friends back in the states that are having fun laughing at me stumbling along and learning (They are both 20 yr plus machinists and High School "friends" ).

You have a really nice design and with just a bit of adjustment it will not only do you proud as a finished build (ha, a machine is never finished), but the quality you put in and care to detail in the build has a direct result on the out come you get. I mean heck with the power supply I finally built and installed for my machine I am running acceleration level in scary land with rather nice rapids. When I get the feeds and speeds right (which is getting more often) I am getting wonderful finishes. Keep it up, doing good.

Michael