Chapter 10 - Installing the ACME screws
Admittedly this is a short chapter compared to the last, but it marks a point where I feel the machine is getting close to looking and soon to be running like it should. As always, here is a picture of the parts required to install the lead screws.
Installing the Z-Axis Lead Screw
Just like the book, I started with the lead screw installation on the Z-Axis. Well, let's just say that it didn't quite go off without a hitch. When I run the screw down to the first nut, it threaded just fine, but going into the second wasn't so easy. Even with the spacers I made for the Z-Carriage, I still didn't have enough clearance on the Z-Beam. I mean it was close, the nut just barely rubbed the Z-Beam. Still it was unacceptable. So, I got out the callipers and went through a bunch of 3/8" washers until I found four that were the same size. I added one to each carriage bearing to give me a little more clearance between the nuts and beam. Next, I didn't really have enough wiggle room on the bottom nut to prevent it from binding when I run the lead screw into it. To remedy this, I removed the 5/16" socket head screws and replaced them with 1/4-20 x 1" long bolts as recommended in the book. After all that, I finally had enough room to shift things around and line up the lead screw. WHEW, hope the rest are not that bad!!!
Installing the X-Axis Lead Screw
Installing the Y-Axis Lead Screws
When I built the Y-Carriages I used the supplied 5/16" socket head cap screws that came with the anti-backlash nuts. After the issues with the Z-Axis, I went ahead and replaced them with the 1/4-20 x 1" bolts before I even started on the lead screw installation. Also, Zachary and I found it helpful to grind down part of the head of the inside motor mount bolts to give a little more clearance for the opposite nut that attached the angle down to the extrusion. This is a tight fit there. Otherwise the Y-Axis lead screws installed just fine.
The machine in its current state
The machine is coming along just fine and I will be starting the electronics portion soon. I think I will turn my attention to the computer rack that will be built into the table next. I have put it off long enough. See you in the next chapter.