Before I started squaring the block, I first trammed the mill to ensure precision throughout the process.
To do this, I made sure the vise was squared to the mill by using a dial indicator and sweeping it along the fixed jaw of the vise.
If the vise was misaligned, I tapped it gently with a mallet until the dial indicator showed it was properly aligned.
Once the vise was squared, I securely clamped the aluminum block in place, ensuring it was held firmly before beginning the machining process and making sure no chips were in the vice by blowing it with air.
I started by facing one side of the block with a face mill to make it flat and smooth (as seen in the photos and video).
After facing, I deburred the edge using a deburring tool to eliminate any sharp edges or debris that could affect accuracy.
With the block now properly prepared, I cut along the X-axis to the specified measurement, using the table's movement to align the tool precisely.
After completing the first side, I rotated the block 90 degrees and machined the next face to ensure it was perfectly perpendicular to the first.
Each time I rotated the block, i gave the vise a pass of air to make sure there is no foreign objects what would get in my way. Then, I carefully clamped it back into place, tap it with a mallet a couple of times to make sure its snug, and double-checked the alignment to maintain accuracy.
I continued rotating and machining the remaining faces, checking the alignment with each turn to ensure all six sides were square to each other.
The goal was to maintain the required tolerance, typically around 0.010" (10 thousandths), so I measured frequently with calipers to check my progress.
After finishing the X-axis faces, I switched to the Y-axis and used an endmill to machine the length of the block, ensuring everything remained within tolerance.
Overall, the process was enjoyable and rewarding. After about an hour of instruction, I felt confident and proficient using the manual mill, and I believe I’m now quite comfortable with the machine.
Setup:
We began by securing a 3-jaw chuck tightly to the lathe by slightly tightening each jaw at a time to make sure the part is centered when it enters the lathe.
The aluminum cylinder was then inserted into the chuck and tightened.
Facing the Cylinder:
We brought the carbide insert to the cylinder, ensuring it just barely touched the surface b making a small engraving on the aluminum cylinder.
The carbide insert was retracted, and we zeroed the Y-axis to establish a reference point for the face of the cylinder.
Using the automatic feed, we fully faced the cylinder. The automatic feed can be better than a human hand because the automatic feed is has a consistant speed, unlike relying on the human senses/
Identifying the Center:
At the cylinder's center, we zeroed the X-axis to mark the midpoint.
Diameter Cut:
We made a small indent and then engaged the auto feed to begin the diameter cut.
The cut was made in increments of 0.050" per pass until the diameter reduced from 1.450" to 1.200" ± 0.005".
We used calipers to measure the diameter after each pass to ensure accuracy.
Switching to the 4-Jaw Chuck:
After completing the diameter cut, we removed the 3-jaw chuck and attached the 4-jaw chuck.
We then learned how to properly center the part using a dial indicator. By spinning the chuck and adjusting the jaws, we achieved a tolerance of 0.002" (0.20 thousandths). How we centered our cylinder in the 4 jaw chuck was frustrating. First you get the dial indicator and make it touch the highest point in the cylinder. You find this by turning the chuck until the dial indicator is at its highest. Then you tighten the 4 jaw chuck by twos, i got taught to do 1 and 3, and 2 and 4. This is because they are opposites and will give you the easiest time. We kept on turning and tightening until the part was centered.
Final Facing and Diameter Cut:
Once the 4-jaw chuck was centered, we faced the end of the cylinder by making a small engraving at the top, then we use the auto feeder to do the rest of the job.
We then performed a single pass to cut the diameter, removing 0.030" from the end.
Below is a picture of me securing the 4-jaw chuck and checking for centering using the dial indicator.