Step 10: Gantry Sides
We are moving right along. We will be making the gantry sides in this video. The gantry is the part of the CNC Router that moves along the x-axis. That's what makes this machine a gantry style machine. The gantry allows the router to essentially float over the cutting surface. The gantry sides consists of two boards approximately 18" x 8" 8" linear slide bearings will also be built in a later video to be used in with these gantry sides. The linear slide bearings are longer than the other linear slide bearings on the y and z axes so the weight of the gantry can be supported. The gantry needs to carry the z-axis, router, and the y-axis with all support pieces. In addition, the force of the motors against the force that the bit and cutting imposes on the machine must be handled by the entire gantry.
The sides of the gantry is pretty simple. All you will need to do is create two grooves on each board to hold the linear slide bearings. The challenge is to make the grooves at a tolerance that doesn't allow play with the linear bearings. There are things we can do to reduce the play if the grooves are too large, like installing screws along the edges of the aluminum angles of the slide bearings to hold its position. If there is interest for me to explain this further, contact me.
The router is used primarily for this step. The router can route out perfect grooves at about 1/8" in depth. I use a 1/4" spiral upcut bit set to a 1/8" depth. Upcut means the wood chips (wood cloud) is pushed upward. The 1/4" size has the ability to make 1" deep cuts. Since we are using 3/4" boards, the 1/4" bit is perfect.