While ITP schedule gets crazier each week, subtraction class & assignments never fail to soothe! Using metal lathe was an enjoyable, satisfying and rewarding experience. Never before in the shop I was so much focused, geared up, and happier.
For the first assignment with basic lathe operations, I used a piece of 1″ aluminum rod and also tried delrin rod. I started with a piece of aluminum Immanuel was using before he finished his assignment. It was partially turned and faced and I learned a few tips from him before I started.
I faced and turned the job, which left a sharp edge around the faced circle. I used slant edge of the facing tool to make it a little blunt. Next I used the parting tool, mainly to see how it feels and how different it is from the facing tool. I made a little notch around the turned surface using parting tool:
Using a lot of oil and precaution, I tried using the turning tool to mark a rather deeper notch on the surface. Although it felt really smooth while operating, the edge has radial marks on it, like that on a knob/ wristwatch crown. This was an unexpected result and I like the effect.
Compared to aluminum, facing and turning delrin was less fun and I didn’t spend much time on it. Here are the two pieces:
Next, I used the aluminum piece to make the doo-dad. I mounted it on the chuck, used the #3 center bit first:
I struggled for a little while with the drill chuck as I wasn’t initially able to install it on the tailstock. I saw a few youtube videos and made sure it is done right before actually drilling the hole. I used 3/32, 3/16 and finally 7/32 bits to gradually drill the hole larger in diameter. Next I stopped the machine completely by pressing the red STOP button and used the tap set. Initially I tried mounting tap on the tailstock and used the wheel on right hand end of tailstock to drive the tap into the job; but somehow the tap always refused to come out. It went in when pushed into the job, but stayed inside when I turned the tailstock wheel back.
Finally I used the key and did it without using the tailstock. I thought of tapping as an operation that would require a good amount of efforts; but it was really smooth. Like Ben had rightly mentioned, this particular aluminum ‘wants to be machined’.
Next I installed the piece with the finished face inside the chuck. Parting needed more attention as there was a lot of material being removed continuously. I used lot of oil:
I used vernier calipers earlier to measure the depth of hole drilled into the piece, and therefore the hole was visible from the other side:
Next I did a little facing and tapping from this face as well. The final machined piece looks like this: