ציטירנדיקער פּירוש אויף ישעיהו 44:12

מעשה חרש אבן means THE WORK OF AN ARTIFICER IN STONES. This word חרש is in close connection (i. e. in the construct state) with the word that follows it and therefore it is punctuated with Patach in its last syllable. Similar is, (Isaiah 44:13) “The חָרַשׁ עצים stretcheth out a line” i. e. the worker in wood. So, also, (Isaiah 44:12) “the worker in (חָרַשׁ) iron maketh an axe.” All these examples of חָרַשׁ are in close connection with the words that follows them and are therefore punctuated with Patach.

the name of the utensil, and with it you hit the peg into the ground. and in Yeshiyahu 44: 12 "And fashions it by hammering."

ולא תבנה אתהן, for if you were to construct it from hewn stone, i.e. involving metal tools, the artisans are in the habit of engraving pictures, symbols, etc. on these surfaces to commemorate themselves or their favourite deities. In order to forestall this, I command you not to use metal tools which could make such engravings. (compare Isaiah 44,12-13)