I needed to bond two metal surfaces for a project that i working on and I'll publish the details once that is up and running. The pieces are a length of flat CRS 1/8" thick x 3/8" wide and 6" long and the other is a section of a small flat file 3" long x 3/8" wide and slightly thinner. I decided to use epoxy but the polished surface of the CRS stock needed to be rough for the epoxy cement to get hold and bond. For that purpose I attached the piece of stock to a block of wood clamped to my milling slide bolted to a bench radial drill with a 1/2" tap in the chuck turning at the lowest speed of the press and using the slide I run the piece against the turning tap a few times which gave me a surface similar to a fine cut file. Here's the set-up.
In the meantime, I ordered a single wheel knurling holder that by turning in the lathe to round shape can be held in my milling machine and any piece run under it by applying pressure to the spindle, will indent the knurls in the soft metal. Such a procedure can be used not only for bonding a smooth surface but also to knurl any flat piece of stock if needed.
More on the finished contraption soon.