Lighting The Lantern

The Rambam Beis Habechirah (3:3-4) says נִמְצְאוּ כָּל הַגְּבִיעִים שְׁנַיִם וְעֶשְׂרִים. וְהַפְּרָחִים תִּשְׁעָה. וְהַכַּפְתּוֹרִים אַחַד עָשָׂר. וְכֻלָּן מְעַכְּבִין זֶה אֶת זֶה וַאֲפִלּוּ חָסֵר אֶחָד מִן הַשְּׁנַיִם וְאַרְבָּעִים מְעַכֵּב אֶת כֻּלָּן: בַּמֶּה דְּבָרִים אֲמוּרִים בְּשֶׁעֲשָׂאוּהָ זָהָב. אֲבָל שְׁאָר מִינֵי מַתָּכוֹת אֵין עוֹשִׂין בָּהּ גְּבִיעִים כַּפְתּוֹרִים וּפְרָחִים.  His source is from Menachos (28a.)  The Achronim ask why is a gold menorah without the adornments פסול, why is it worse than a menorah made out of other metals?  The Gemorah (ibid) says that the menorah must have 7 branches for it says כפתוריהם וקנותם ממנה יהיו, the word יהיו tells us that it must be the way the possuk says (Gemorah and Rashi.)  The Masseh Yad cites the Briskor Rav asks why do we need a local din over here, it should be מעכב because of the din said by all כלי מקדש that they have to be maid according to the prescribed measurements as the possuk says הַכֹּ֥ל בִּכְתָ֛ב מִיַּ֥ד י״י֖ עָלַ֣י הִשְׂכִּ֑יל כֹּ֖ל מַלְאֲכ֥וֹת הַתַּבְנִֽית and the Gemorah in Chullin (83b) and Eruvin (104a) is clear that we learn from here the measurements are exact?  [The assumption of the question is subject to debate is the din of הַכֹּ֥ל בִּכְתָ֛ב מִיַּ֥ד י״י֖ עָלַ֣י הִשְׂכִּ֑יל is מעכב and if it applies להלכה, but we will grant the assertion.]  [Also, I didn't find this question in the Briskor Rav, I did see it in the Rinas Yitzchak in the name of Rav Dovid Solevtchik who spells out he's asking according to Rac Chayim that holds הַכֹּ֥ל בִּכְתָ֛ב מִיַּ֥ד י״י֖ עָלַ֣י הִשְׂכִּ֑יל is מעכב.]  The Rav (or Rav Dovid) answers that the rule of הַכֹּ֥ל בִּכְתָ֛ב מִיַּ֥ד י״י֖ עָלַ֣י הִשְׂכִּ֑יל says that vessel isn't considered part of the mikdash; in case in point the menorah won't be kosher to be the menorah of the mikdash.  However, the vessel still has the status of a kli sharash and therefore one would be able to fulfill the mitzvah of lighting the menorah with it.

Similarly, says the Masseh Yad, regarding the menorah without the גביעים וכפתורים.  A non-gold menorah isn't kosher for the mitzvah of having a menorah as part of the mishkan. It is a valid keli that one may use to fulfill the mitzvah of lighting, but it isn't part of the mikdash. Therefore, we can say yes, a menorah without גביעים וכפתורים is no worse than a menorah of other metals. However, that only makes it kosher for lighting. The halacha that says its מעכב is in reference to being kosher as the menorah of the mikdash; that it is not. (The idea is already mentioned in מכתבי תורה from the Rogatchover #79.)