I made this from mostly scrap. 1.5" Aluminum angle, Salvaged aluminum blocks, aluminum disc from metal poured into a can, 3/8" all thread. The movable block was slotted 1/8"+ with a slitting saw. It is used by clamping it over the target metal, holding a steel letter stamp against the moveable aluminum block, tap to imprint metal, advance the guide while aligning the double indicator lines to the center of the next letter. The idea was that I could use computer kerning and get nice straight lines of letters or numbers. Might have worked but the letters are not centered on my cheap set of stamps. The hand wheel advances the alignment block 1/16 / rev. The 1/4" Lexan has black scribe lines top & bottom to eliminate parallax.