ייִדישער מחשבֿה אויף שמות 27:10

The verse uses the word ְחִשֻּׁקֵיהֶם to refer to the wheels’ rims. The rims connect the spokes, which are referred to as חִשֻּׁרֵיהֶם. The term חִשֻּׁקֵיהֶם is also used when the Torah discusses the Mishkan:⁸See Shmos 27:10. “Their bands (חִשֻּׁקֵיהֶם) were silver.” The rim of a wheel is the part of the wheel that revolves and is in contact with the earth. Usually, wheels have an iron rim. Thus, the mishnah⁹Keilim 11:3. mentions “an iron rim.” In this instance, it was not necessary for the wheels to have an iron rim, because the wheel was made entirely of copper.¹⁰Copper is both ductile and tough, making it easy to shape into wheels and sturdy enough not to need an outer iron rim.