CNC Router Construction

Over a few days, I (with the help of my father) managed to complete the mechanical structure of the CNC router.  I purchase 4' x 8' x 3/4" MDF (Medium Density Fiberboard) at Home Depot for about $32.00.  I tried Lowels first... but apparently they do not cut that material in the store (their loss).

Day 1:
Today started at 8am and finished at 7pm.... a long day.  The wood cutting part was easy. The picture below  shows our progress after a few hours.

Main Structure Assembly

The difficult and time consuming part was aligning the precision rod such that the X table can slide freely.  I had a feeling this would be difficult, but it ended up being harder than expected.  The precision rod has a tolerance of +.000 / -.0005 (yes, thats 1/2 of one thow) and the bearings have a tolerance of +.001 / +.002.  This means the rods have to be parallel within about .001".  We 'fixed' the problem by opening up the inside diameter of the bearing with a Dremel (not recommended but effective).

The below image shows the progress at the end of day 1.

Assembly after day one

Day 2:
Today, I spent about two hours making the Z-table (up-down direction).  Using the lessons I learned from the X-table difficulties, I managed to make the bearings slide by taking everything slow and match-drilling when possible.

Full Assembly - Awaiting Rod Engs

YZ Carriage - Y is left and right, Z is up and down

Day 3:
Today, I spent another 2 hours finishing the remaining parts. mostly the rod end holders.  These rod end holders allow me to adjust the rods to align the table.  There are clearance holes in the main structure and tight fitting holes (drilled using Forstner Bits from Harbor Freight ~$10) which hold the rods in place and secure them to the main structure (shown in the image below, the block of wood at the very front of the structure with the four bolts).

Finished XYZ Table

Next, I have to adjust the axes to allow them to move more freely and order the motors and drivers.