I have had a few days out working on the CNC machine without posting, so I figure I should put in some kind of update.
When we last left the build, I had attached the z table and all its bearings.
I spent a couple minutes getting the z axis motor mount installed as best I could. I need some more hardware for this, more on that later.
The next order of business was to drill the holes in the x axis rails. They were already clamped to the table, but after thinking it over, I only drilled the first pilot hole and then used the drill press to drill holes in the rest of the rail. In this way, I had a good reference ( the holes in the rails lined up ), and I could use that to ensure that the rails were square ( using a carpenters square ) down the table edge, despite the edge not being even, and having no other reference to work from. This felt like a somewhat advanced woodworking maneuver, and I came up with it on my own. W00t.
After one short session on Sunday, I had the first rail installed.
The second rail was aligned to the first by the simple expedient of using the gantry itself to make sure that the spacing was correct. It is possible that the gantry sides are not quite parallel, but this won’t be a problem I think. The second rail went on quickly, and I was able to get the rear bottom bearings on both sides of the x axis by the time I had to quit for the night. By the way, I need to figure out how to deal with aluminum swarf as opposed to sawdust. It feels wrong to just trash it or to mix the two, if at all possible to avoid.
That was Monday, or maybe Tuesday. I think I took a day off in there somewhere; the furnace went out in the house and I was paying attention to that.
Tonight, I quickly got the final two bearings installed on the x axis, and installed the four x axis idler sprockets also. The lower bearings for the x axis seem like they are a little too tight. I have them at the extreme end of their travel, and I had to force the axis rails between the bearings. I don’t even have the adjuster cross dowel in yet. This will take some monitoring.
I moved on to installing the x axis chain mounts. There is one at each corner of the machine, each one consists of three pieces that are cross doweled together and then bolted to the table. I was able to get all four installed before I had to quit for the night.
I am nearly out of wooden pieces. I think that all that’s left is the little teeny chain tensioner pieces, which will go on pretty quickly. I am essentially done with the wood portion of the construction, and now have to move on to installing motors and then chains.
I need to drop by Tacoma Screw one more time, to get some more fully threaded machine screws for the z axis motor mount. I also need to figure out how to mount the z axis transmission nut, as I am not using the parts suggested by the kit. Should be straightforward though.
There are a couple more sessions of assembly, add on one more to get the computer and router installed, and I should be cutting in the next few days! This seemingly endless project feels really close to a conclusion. I look forward to first sawdust.