Answered By: Gail Bardhan Last Updated: Jul 19, 2016 Views: 8
"After ten months... The glass and its mold are lowered from the annealer kiln, the steel rim is taken off, and the mold material is removed. A wooden frame of heavy timber is then bolted around so as to frame the disc. It is then stood up on edge and the ceramic cores are cleaned out, that is, removed. The disc is then inspected for strain, polarized light being used in this testing."
An article by George McCauley says "Removing the cores from the ribs of the disk and cleaning its surface is accomplished with a sharp-edged bar and a sandblast and presents no great problem; except, of course, great care must be exercised, if a bar is used, that the glass be not struck too severely. Removing the cores with a bar must be classed more as work than as a problem. The sandblast works slower, with more dust, but easier, and is ideal for cleaning the entire surface that has been in contact with the mold. (Bulletin of The American Ceramic Society, v. 14, no. 9, Sept. 1935)
We do have a bibliography listing many of the books and articles which discuss the making and shipping of the disc. You may ask your librarian to contact us for materials not in your library. If they are available through interlibrary loan, we will be happy to provide them.