We did a lot of knurling '40s- '60s on many rebuilds. Often in chassis. It worked for budget jobs when you were honing a couple thou to freshen/ straighten bores. Haven't done that for decades.There were other ways to expand a piston which were a better method IMO. Still have the eqpt. Typical OE cast pistons could be knurled. Only do it on minor thrust side. Thorough knowledge of later alloys is important prior to any attempts.
Usually had to machine ring grooves and use GI inserts, too. Lots of labor, but at 65 cents per hr w/ 2 kids we worked lots of hrs. David
