אורח חיים רנ״טOrach Chayim 259

Se’if 1א׳

מוּכִין, (פי' כָּל דָּבָר רַךְ קָרוּי מוּכִין כְּגוֹן צֶמֶר גֶּפֶן וּתְלִישֵׁי צֶמֶר רַךְ שֶׁל בְּהֵמָה וּגְרִירַת בְּגָדִים בְּלוּיִים), שֶׁטָּמַן בָּהֶם דֶּרֶךְ מִקְרֶה, אָסוּר לְטַלְטְלָן אֶלָּא מְנַעֵר הַכִּסוּי וְהֵן נוֹפְלוֹת; וּכְגוֹן שֶׁמִּקְּצָתָן מְגֻלֶּה, שֶׁאֵין זֶה טִלְטוּל אֶלָּא מִצִּדּוֹ. וְאִם יִחֲדָן לְכָךְ, מֻתָּר לְטַלְטְלָן. אֲבָל אִם טָמַן בְּגִזֵּי צֶמֶר, אֲפִלּוּ לֹא יִחֲדָן לְכָךְ, מֻתָּר לְטַלְטְלָן. וְהָנֵי מִלֵּי סְתָם גִזִּין שֶׁאֵין עוֹמְדִין לִסְחוֹרָה, אֲבָל אִם נְתָנָם לְאוֹצָר לִסְחוֹרָה, צְרִיכִין יִחוּד וְאִם טָמַן בָּהֶם בְּלֹא יִחוּד, מְנַעֵר הַכִּסוּי וְהֵן נוֹפְלוֹת, דְּהַיְנוּ: לוֹמַר שֶׁנּוֹטֵל כִּסוּי הַקְּדֵרָה שֶׁיֵּשׁ תּוֹרַת כְּלִי עָלֶיהָ, וְאַף עַל פִּי שֶׁהֵם עָלֶיהָ לֹא אִכְפַּת לָן, דְּלֹא נַעֲשֵׂית בָּסִיס לָהֶן.

1. Several Laws Governing Insulation and Moving the Insulating Materials, 7 Seifim: Since they are muktzeh, on Shabbos, it is forbidden to move muchin (any soft substance, e.g., cotton, the soft wool of an animal, or the remnants of worn out clothes.” In this section, we are speaking about muchin that are dry, for muchin that are wet are considered as substances that increase temperature and are forbidden to be used for insulation) that were used on Friday to insulate a pot on the spur of the moment. Rather, he should shake the cover and it will fall (on its own) e.g, its muktzah is uncovered, and this is not considered 'moving'. However, if it was insulated with fleece wool, even if it was not designated for that purpose, it is permitted to move it. This refers to fleece that is not set aside for commerce. However if they are for merchandise they must be set aside. If one insulates with them without them being set aside, one shakes the cover and they fall off, that is to say, when the cover of the pot is considered as a k’li. Even though they are on top of it, we are not worried about it, because we do not make a Basis for them.

Se’if 2ב׳

הַנּוֹתְנִים אֲבָנִים וּלְבֵנִים סְבִיב הַקְּדֵרָה צָרִיךְ שֶׁיְּיַחֲדֵם לְכָךְ לְעוֹלָם, שֶׁהֲרֵי כָּל זְמַן שֶׁלֹּא יִחֲדָן אֵינָם חֲשׁוּבִים לוֹ וּמַשְׁלִיכָן. הִלְכָּךְ אָסוּר לְטַלְטְלָן, אִם לֹא שֶׁיַּצְנִיעֵם וּמְיַחֲדָן לְכָךְ.

Those who place stones and bricks around a pot (for insulation) must permanently designate them for that purpose (so that it will be permitted to move them on Shabbat). For as long as they are not designated for that purpose, they are not considered important to a person and he may cast them away. Therefore, it would be forbidden to move them if they were not set aside and designated for that purpose

Se’if 3ג׳

הַטּוֹמֵן בְּקֻפָּה מְלֵאָה גִּזֵּי צֶמֶר שֶׁאָסוּר לְטַלְטֵל וְהוֹצִיא הַקְּדֵרָה, כָּל זְמַן שֶׁלֹּא נִתְקַלְקְלָה הַגּוּמָא יָכוֹל לְהַחְזִירָהּ; וְאִם נִתְקַלְקְלָה, לֹא יַחֲזִירֶנָּה. וַאֲפִלּוּ לְכַתְּחִלָּה יָכוֹל לְהוֹצִיאָה עַל דַּעַת לְהַחְזִירָהּ אִם לֹא תִּתְקַלְקֵל, וְלֹא חַיְישִׁינָן שֶׁמָּא יַחֲזִירֶנָּה אַף אִם תִּתְקַלְקֵל. וְיֵשׁ אוֹמְרִים שֶׁאֲפִלּוּ טָמַן בְּדָבָר שֶׁמֻּתָּר לְטַלְטֵל, אִם נִתְקַלְקֵלָה הַגּוּמָא, לֹא יַחֲזִיר מִפְּנֵי שֶׁתִּצְטָרֵךְ הַקְּדֵרָה לַעֲשׂוֹת לְעַצְמָהּ מָקוֹם כְּשֶׁמַּחֲזִירָהּ וְנִמְצָא כְּמִי שֶׁטּוֹמֵן בְּשַׁבָּת.

When a person insulated [a pot of food] in a container full of muchin that are forbidden to be moved, once he removed the pot from there in the prescribed manner, he may return it there, as long as the hollow [in which the pot had been placed] remains intact. If, however, the hollow did not remain intact, it is forbidden to return it. Nevertheless, as an initial preference, one may remove the pot with the intent of returning it, [provided the hollow remains intact]. We are not concerned that he may widen the hollow if it does not remain intact. There are those who say that even if one insulates with a substance that is permissible to move, if the hollow remains intact one may not return it, because the pot would need to have a place made for itself to be grasped, as we find regarding one who insulates on Shabbat.