Describe packing experiments (mostly following Rummonds).
After building the tympan-frisket assembly and adjusting the casters supporting the bed, I added packing to the cylinder. The aim was to achieve a minimal impression on a thick piece of paper; then, for thinner pieces of paper, I plan to add packing to the top of the tympan.
On the cylinder, I used 8 pieces of 0.01" mylar held in place by a single piece of tympan paper. Note that the 8 pieces relates to how I happened to set the casters on my press; a different setting would require a different number. Having prepared my cylinder, I hope never to touch it again (well, hardly ever).
On my tympan, I have 3 more pieces of thick mylar: one below the tympan, right against the paper, and two more above the tympan. Any required packing and makeready will be placed between these last two pieces.
Since the mylar is effectively incompressible, this approach achieves a hard packing. By changing the amount of packing, I can change the depth of impression, but the hard packing will prevent the impression from showing through the back of the paper.
If some show through is desired, a deboss, then a piece of paper (we'll call it packing paper) can be placed between the mylar and the printing paper to achieve a softer packing. While the mylar won't compress, the packing paper will, allowing the type to press though the printing paper. While I've talked about packing paper, it may be that other materials will work better (Kimlon, from NA Graphics, might be best). Experiments are required!