After coming up with the new clamp design last week (see previous posts), I finally got around to machining it. Not going to lie, I was a little bit dreading since my last aluminum project failed.
I designed the clamp fixture to match some 6061 stock I had already to make it easier on myself. I decided to use the recommended speeds and feeds for cutting aluminum by Pocket NC, and it seemed to work pretty well though a bit slow. I'm using a three flute 1/8" square endmill at approx 20 IPM. The local machinist was giving me some tips on machining it and told me to move the endmill farther into the tool holder; he said you only want it 0.01" more than what your most extended depth is to get the most rigidity out of it. That alone improved the sound of the milling by quite a bit.
I was also looking into coolant systems for the Pocket NC and asked around one of the Facebook groups, where I heard someone using it and ruining one of the belts in the table/bed. The machinist suggested I use coolant, even a light misting every hour would make a world of difference; however, after talking to the people at Pocket NC, they urged me not to. However, midway through the operation, when I was sending a few videos of it running to the machinist, he suggested I try coconut oil on a brush and lightly dab the part about to be milled, just a drop or two. I tried it and holy smokes; it improved the sound tremendously, and I even cracked the feed rate up by 20% without any change in noise.
After doing a 3D adaptive, I did a few pocket clearing and facing operations to cut the holes and clean the sides. I, unfortunately, I wasn't able to finish it due to time restrictions, but I will pick up where I left off tomorrow. Overall very pleased with the outcome thus far.