Both rings installed on a piston. The rings
are dark because of heat treatment.
Note the shoulder on the piston rod, where
the piston itself rests. To produce this, I
had to make the rod out of 1/2" stock
whittled down to 1/4" for most of its length.
Have your lathe carefully lined up before
doing a job like this: if the rods are
tapered, you're likely to have packing
By the way, the gray background is that
little shop-made lapping plate again.