Chapter 6 - X-Beam
Materials for the KRMx01 X-Beam
Installing the X-Beam
The beam has the bolts slid on for the rails and has been bolted to the Y-Carriages. I must admit, the bolts on the inside of the angles of the carriages are fun to get at if you have large hands. Also, I would recommend having a helper when it comes time to square the beam to the carriage and tighten the nuts. Thankfully, my son Zachary helped me, and on his birthday too. Happy 18th Birthday son. I love you.
NOTE: The extrusion for the X-Beam should hang over about an inch or so on each side. The important part is that it clears the Y-Carriage supports. With the modification I made to the Y-Carriages using the spacer for the new anti-backlash nuts, I ended up with the supports extending past both ends of the X-Beam by about 1/16 of an inch. To rectify this, I may need to modify the bearing supports further. I will detail what I done in the section on the motor and bearing mounts. On a new build, I would recommend cutting the table top a 1/4" narrower than the plans call for and move the left Y-Beam in by 1/4".
Zachary and I could not help but to test out the newly installed Y-Carriages and X-Beam. This is a nice smooth rolling assembly. You can watch it in motion in the video below. Zachary is playing the part of the CNC drive motor. As I recall, at two years old he made a really good tricycle motor too!! :-)
Preparing the rails for the X-Beam
Next in line is preparing the X-Beam rails. The little height gauge I bought is really starting to pay for itself on this project. I have always marked the aluminum angle from the outside forcing me to sit the inside of the angle on some stack wood to drill it. This way, I can mark it from the inside and just lay it on it's face to punch and drill. Now, I still want to lay it on some wood when I drill to support the aluminum so it does not distort. But I digress. The first image shows the rails marked, punched and ready for drilling. The second image shows the rails drilled and deburred, ready for installation.
Installing the rails
Here Zachary is tightening the bolts on the rails. We started by clamping a piece of 3/4" MDF across the entire face of the X-Beam. Next the rail is clamped to the MDF at the center and towards the ends. The bolts are progressively tightened starting from the middle and working our way to the ends moving the clamps on the rails as we go along.
Conditioning the rails
Next the rails are conditioned to make them ready for the X-Carriage. This little device used to condition the rails works quite well. You can see some information on the construction of the rail conditioner in chapter 1 of the build.
For the fun of it, we have included a short video showing Zachary using the conditioning board on the rails. GO ZACH GO!!! :-D
Adjusting the X-BEAM to the table
Next, we make sure that the face of the X-Beam is perpendicular to the table. Ours was spot on on both side making no adjustment necessary. I don't know if that is SKILL or just dumb luck. But it was a good sign nonetheless.
The completed KRMx01 X-Beam Assembly
Here are a couple of shots of the completed X-Beam and the machine. Next up is the X-Carriage. I suspect that there will be modifications to it like there were to the Y-Carriages because of the new nuts. Tune in to the next chapter where we build the X-Carriages and find out! See you there.