Joel Oostdyk

Cardell Taylor

12/11/99

EGR 367

The objective for our group was to machine the bed for a CNC-mill. The steps used are in the process plan shown below in Figure 1.

Figure 1- Process plan for the CNC-mill bed

For reference, the drawing of the part can be seen in Figure 2, and the complete CNC-mill can be seen in Figure 3.

Milling the plate turned out to be much more difficult than anticipated. This is because the ways of the mill would not reach all sides of the plate. One side of the plate would have to be set up, checked to be parallel using dial calipers, milled, and then reversed for the other side to be machined.

The mill used did not have working digital read-outs either. Therefore, the accuracy of the dimensions of the pate severely diminished to the accuracy of rulers.

Another unexpected happening is that the original plate was to be 18" by 15". After the sides of the plate had been machined, a 'mystery' person cut off a 4" by 15" section of the plate. The hole pattern and design of the plate had to be modified because of this. The fortunate thing about this is that if the person had cut off more of the aluminum, we would have had to start all over with a new piece because there would not have been room for the mounting screws.

A CNC-mill bed was machined as part of a class project. Despite difficulties, the bed was completed within tolerances. Another group then modified the bed to fit the drive motors.