In the English version of Shemirath Shabbath k'Hilchata (11:10), R' Yehoshua Neuwirth is strict and writes:
When removing the shell from an egg, one should be careful not to
break through any letters or designs which may be stamped on it.
but he is most likely speaking of hand-removing the shell while your case is slightly different.
I believe that, ...
R. Ya’akov Emden seems to have been bothered by this question. In his marginalia (printed at the back of many editions of the Talmud) he wrote:
נ״ל צ״ל ממחק דהיינו מחליק
It seems to me that the correct text is ממחק i.e. smoothing.
(Some contemporary editions of the Talmud print this suggestion in the margin of the page itself, e.g. see note (כ in ...
Most questions of "new cases" within the laws of Shabbos, are best approached by looking at the source reason behind the prohibited melachah; and then continuing into the reasons and/or framework we know of, for any Rabbinical fence.
Two of (of the 39) the works prohibited on Shabbos are writing, and erasing.
In the Mishkan, writing was performed when ...