The change-gear cover on my lathe was held on using some very poorly made allen/hex style bolts. These were a pain to remove each time you wanted to change gears, but I’d seen on a few websites that people had made some knurled knobs with a threaded shaft to hold the cover down instead.
I made these in two parts, after machining both sections they were pressed together. The knurled knob was made from 20mm round aluminium; cleaned up, faced, 9mm hole drilled down the middle and then knurled. The knurling turned out very well, this was the first time I’d used the tool and I think luck played a large part in getting the size right. I made the 2 knobs from the one bit of stock, did the rough shaping and then parted them off. This let me match the size and also get the chamfers to match as I did them at the same time without changing tools.
The shafts were made from 10mm round aluminium; cleaned up, faced, took the size of most of the shaft down to 5mm, threaded the end and then took the remainder of the shaft to a fraction over 9mm ready to be pressed into the knurled section. Making it this way saved on aluminium stock and reduced the time needed to take the size of the stock down to the required size.