Hi Ron, It looks like Expert glues them in and they come already mounted in a bar.
The earliest DD styli were bare diamonds soldered into the bar. It was found that these were prone to breakage and so Edison put the diamonds in tongs and then plated the diamond in the tong with nickel. The nickel encased diamond was then polished to a conical shape and the tip was ground and polished at the same time. The polishing removed the nickel and shaped the diamond stylus tip, like a wooden pencil being sharpened, the wood is removed and the graphite is given a point. You polish a diamond with diamond chips or dust impregnated on disc, I believe. The nickel encased, polished diamond was then soldered into the stylus bar. Below is an exact quote, I cannot include the photo so I used a different description to help. According to Edison Diamond Disc Re-Creations records & artists 1910-1929 page 107: In this process the diamonds were first silver plated, then mounted on rods with paraffin, plated for 72 hours with nickel layers electro deposited under tension. The styli were thus held under layers of nickel at thousands of pounds of pressure. The nickel-encased diamonds were then polished to conical shape, the nickel at the stylus point being found away as the diamond was polished. The finished stylus was then soldered into its stylus bar. In the early days, bare diamonds were just soldered into bars and were prone to breakage when carelessly lowered onto the record. Steve > How are DD styli held into the stylus bar and what does one use to fasten > in > a new one? > > Ron L
