Halacha

הלכה א
כְּלִי עֵץ הָרָאוּי לְמִדְרָס שֶׁקְּבָעוֹ בְּכֹתֶל בְּתוֹךְ הַבִּנְיָן. קְבָעוֹ בַּכֹּתֶל וְלֹא בָּנָה עַל גַּבָּיו אוֹ בָּנָה עַל גַּבָּיו וְלֹא קְבָעוֹ עֲדַיִן מִתְטַמֵּא בְּמִדְרָס כְּשֶׁהָיָה. קְבָעוֹ בְּמַסְמְרִים וּבָנָה עָלָיו טָהוֹר. וְכֵן מַפָּץ שֶׁנְּתָנוֹ עַל גַּבֵּי הַקּוֹרוֹת קְבָעוֹ וְלֹא נָתַן עָלָיו אֶת הַמַּעֲזִיבָה אוֹ שֶׁנָּתַן עָלָיו אֶת הַמַּעֲזִיבָה וְלֹא קְבָעוֹ מִתְטַמֵּא בְּמִדְרָס. קְבָעוֹ וְנָתַן עָלָיו אֶת הַמַּעֲזִיבָה טָהוֹר:
כסף משנה
1.
The following rules apply to wooden keilim that are fit to serve as supports that were permanently affixed to a wall in a building. If they were fixed in a wall, but nothing was built upon them or something was built upon them, but they were not permanently attached to the wall, they are still susceptible to midras impurity, as before. If they were affixed to the wall with nails and then one built over them, they are pure.
Similarly, when a mat was placed over beams, if it was affixed there, but a ceiling was not built over it or a ceiling was built over it, but it was not affixed, it is still susceptible to midras impurity. If it was affixed and a ceiling was built over it, it is pure.

הלכה ב
סַפְסָל שֶׁנִּטַּל אֶחָד מֵרָאשָׁיו עֲדַיִן הוּא רָאוּי לְמִדְרָס. נִטַּל הַשֵּׁנִי טָהוֹר. וְאִם יֵשׁ בּוֹ גֹּבַהּ טֶפַח מִתְטַמֵּא בְּמִדְרָס:
כסף משנה
2.
When one of the legs of a bench was removed, it is still susceptible to midras impurity. If the other leg is also removed, it is pure. If, however, it is a handbreadth high, it is susceptible to midras impurity.

הלכה ג
כִּסֵּא שֶׁל כַּלָּה שֶׁנִּטְּלוּ חִפּוּיָיו טָהוֹר וְאִם לֹא הָיוּ חִפּוּיָיו יוֹצְאִים וְנִטְּלוּ עֲדַיִן הוּא רָאוּי לְמִדְרָס שֶׁכֵּן דַּרְכּוֹ לִהְיוֹת מַטֵּהוּ עַל צִדּוֹ וְיוֹשֵׁב עָלָיו:
כסף משנה
3.
When the ornamental coating of a bride's chair was removed, it is pure. If the coating of a chair did not project outward and was removed, the chair is still susceptible to midras impurity, because it is the ordinary practice to turn it on its side and sit on it.

הלכה ד
כִּסֵּא שֶׁנִּטְּלוּ חִפּוּיָיו וַעֲדַיִן הוּא רָאוּי לִישִׁיבָה מִתְטַמֵּא. נִטְּלוּ שְׁנַיִם מֵחִפּוּיָיו זֶה בְּצַד זֶה טָהוֹר:
כסף משנה
4.
When the coating of a chair was removed and it is still fit to be sat upon, it is susceptible to impurity. If two of its coatings, one next to the other, were removed, it is pure.

הלכה ה
שִׁדָּה שֶׁנִּטַּל הָעֶלְיוֹן שֶׁלָּהּ טְמֵאָה מִפְּנֵי הַתַּחְתּוֹן שֶׁהוּא רָאוּי לְמִדְרָס. נִטַּל הַתַּחְתּוֹן טְמֵאָה מִפְּנֵי הָעֶלְיוֹן. נִטְּלוּ שְׁתֵּיהֶן הֲרֵי הַדַּפִּין טְהוֹרִין:
כסף משנה
5.
When the upper portion of a closet is removed, it is still impure because of the lower portion, because that portion is fit to use as a support. If the bottom portion was removed, it is impure because of the upper portion. If they were both removed, the side frames are pure.

הלכה ו
תֵּבָה שֶׁנִּפְחֲתָה מִצִּדָּהּ מִתְטַמְּאָה בְּמִדְרָס וּבִשְׁאָר טֻמְאוֹת מִפְּנֵי שֶׁרְאוּיָה אַף לִישִׁיבָה וְהַכּל יוֹשְׁבִין עָלֶיהָ. נִפְחֲתָה מִלְּמַעְלָה טְהוֹרָה מִן הַמִּדְרָס שֶׁהֲרֵי אֵינָהּ רְאוּיָה לִישִׁיבָה וּמִתְטַמְּאָה בִּשְׁאָר טֻמְאוֹת שֶׁעֲדַיִן הִיא מְקַבֶּלֶת. נִפְחֲתָה מִלְּמַטָּה טְהוֹרָה מִכָּל טֻמְאוֹת אַף עַל פִּי שֶׁאֶפְשָׁר לֵישֵׁב עָלֶיהָ בְּכִסֵּא מִפְּנֵי שֶׁעִקַּר מַעֲשֶׂיהָ לְקַבָּלָה וּכְבָר בָּטַל הָעִקָּר. וְהַמְּגוּרוֹת שֶׁלָּהּ מִתְטַמְּאוֹת וְאֵינָן חִבּוּר לָהּ. וְכֵן מַשְׁפֶּלֶת שֶׁנִּפְחֲתָה מִלְּקַבֵּל רִמּוֹנִים אַף עַל פִּי שֶׁרְאוּיָה לְמִדְרָס הֲרֵי הִיא טְהוֹרָה מִכְּלוּם מִפְּנֵי שֶׁעִקַּר מַעֲשֶׂיהָ לְקַבָּלָה וְהוֹאִיל וּבָטַל הָעִקָּר בָּטְלָה הַטְּפֵלָה:
כסף משנה
6.
When a chest is broken open at its side, it is susceptible to midras impurity and other types of impurity, because it is still fit to sit on, and indeed everyone sits on it. If it was broken open from above, it is pure with regard to midras impurity, for it is no longer fit to sit on. It is, however, susceptible to other impurities, because it is still a receptacle. If it is broken open from below, it is pure from all types of impurity. The rationale is that even though it is still possible to sit on it like a chair, since its fundamental purpose was to serve as a receptacle and that fundamental purpose has been nullified, its secondary purpose is not considered significant. Its drawers are subject to impurity and are not considered as joined to it.
Similarly, a basket that serves as a dispenser which is broken open to the extent that it cannot hold pomegranates is entirely pure even though it is still fit to serve as a support. The rationale is that its fundamental purpose was to serve as a receptacle and since that fundamental purpose has been nullified, the secondary purpose is also nullified.

הלכה ז
עֲרֵבָה שֶׁל עֵץ שֶׁמְּגַבְּלִין בָּהּ הַבִּנְיָן אוֹ אֶת הַגְּפָסִים אַף עַל פִּי שֶׁמְּקַבֶּלֶת שְׁאָר טֻמְאוֹת אֵינָהּ מִתְטַמְּאָה בְּמִדְרָס. וְשֶׁלָּשִׁין בָּהּ אֶת הַבָּצֵק שֶׁמְּחַזֶּקֶת מִשְּׁנֵי לוֹגִין וְעַד תִּשְׁעָה קַבִּין שֶׁנִּסְדְּקָה עַד שֶׁאֵינוֹ יָכוֹל לִרְחֹץ בָּהּ רַגְלוֹ אַחַת מִפְּנֵי הַסֶּדֶק הֲרֵי זוֹ מִתְטַמְּאָה בְּמִדְרָס שֶׁסְּתָמָהּ שֶׁכּוֹפְתָהּ וְיוֹשֵׁב עָלֶיהָ לְפִי גָּדְלָהּ וְסֶדֶק שֶׁלָּהּ. הִנִּיחָהּ בַּגְּשָׁמִים עַד שֶׁנִּתְפְּחָה וְנִסְתַּם הַסֶּדֶק אֵינָהּ מִתְטַמְּאָה בְּמִדְרָס שֶׁהֲרֵי הִיא רְאוּיָה לָלוּשׁ בָּהּ וּתְחִלַּת מַעֲשֶׂיהָ לָלוּשׁ בָּהּ וּמְקַבֶּלֶת שְׁאָר טֻמְאוֹת. חָזַר וְהִנִּיחָהּ בַּקַּדִים וְנִפְתַּח הַסֶּדֶק חָזְרָה לְקַבֵּל טֻמְאַת מִדְרָס וּטְהוֹרָה מִשְּׁאָר טֻמְאוֹת:
כסף משנה
7.
A mixing trough made from wood in which building materials and gypsum are mixed is not susceptible to midras impurity even though it is susceptible to other forms of impurity.
When a kneading trough used to knead dough that holds between two luggin and nine kabbin has been cracked to the extent that one cannot wash even one foot in it because of the crack, it is susceptible to midras impurity. The rationale is that mostly likely it will be turned upside down and sat upon, because of its size and because of its crack.
If the cracked kneading trough was left in the rain until its wood swelled and the crack closed, it is no longer susceptible to midras impurity, for in its present state, it is fit to knead dough and, initially, that was its purpose. It is susceptible to other types of impurity. If, afterwards, one left it exposed to the east wind, and the crack opened, it becomes susceptible to midras impurity again and is pure with regard to other types of impurity.

הלכה ח
עֲרֵבָה גְּדוֹלָה שֶׁהִיא יֶתֶר עַל תִּשְׁעָה קַבִּין שֶׁנִּפְחֲתָה מִלְּקַבֵּל רִמּוֹנִים וֶהֱכִינָהּ לִישִׁיבָה הֲרֵי זוֹ טְהוֹרָה אַף מִטֻּמְאַת מִדְרָס עַד שֶׁיַּקְצִיעַ שֶׁאֵין הַמַּחְשָׁבָה מוֹעֶלֶת בַּעֲרֵבָה גְּדוֹלָה שֶׁנִּפְחֲתָה עַד שֶׁיַּעֲשֶׂה בָּהּ מַעֲשֶׂה. עֲשָׂאָהּ אֵבוּס לִבְהֵמָה אַף עַל פִּי שֶׁקְּבָעָהּ בַּכֹּתֶל טְמֵאָה בְּכָל הַטֻּמְאוֹת:
כסף משנה
8.
When a large kneading trough that can hold more than nine kabbin that was damaged and cannot hold pomegranates was prepared to be sat upon, it is pure even from midras impurity until the corners were trimmed. The rationale is that one's intent does not have an effect on the status of a large kneading trough that was damaged unless one performs a deed to make it fit for that purpose. If he made it a feeding trough for animals, it is susceptible to all types of impurity even if it was affixed to a wall.

הלכה ט
מִטָּה שֶׁנִּטְּלוּ שְׁתֵּי אֲרֻכּוֹת שֶׁלָּהּ אַחַר שֶׁנִּטְמֵאת וְעָשָׂה לָהּ אֲרֻכּוֹת חֲדָשׁוֹת וְלֹא שִׁנָּה אֶת הַנְּקָבִים וְנִשְׁבְּרוּ הַחֲדָשׁוֹת עֲדַיִן הִיא בְּטֻמְאָתָהּ. נִשְׁתַּבְּרוּ הַיְשָׁנוֹת טְהוֹרָה שֶׁהַכּל הוֹלֵךְ אַחַר הַיְשָׁנוֹת:
כסף משנה
9.
When the two long sideboards of a bed were removed after it contracted impurity and new sideboards were made for it, but the holes used to attach the sideboards to the headboards were not changed, the bed, including the new sideboards remains impure. Even if the new sideboards are broken, the bed is still impure. If the old sideboards are broken, it is pure, because the status of the entire bed depends on the old sideboards.

הלכה י
מִטָּה שֶׁהָיְתָה טְמֵאָה מִדְרָס וְנִטְּלָה קְצָרָה וּשְׁתֵּי כְּרָעַיִם עֲדַיִן הִיא בְּטֻמְאָתָהּ שֶׁעֲדַיִן צוּרַת הַמִּטָּה עוֹמֶדֶת. נִטְּלָה אֲרֻכָּה וּשְׁתֵּי כְּרָעַיִם טְהוֹרָה:
כסף משנה
10.
When a bed had contracted midras impurity and a short board and its two legs were removed, it is still impure, because it still has the form of a bed. If one of the sideboards and its two legs were removed, it is pure.

הלכה יא
קִצֵּץ שְׁתֵּי לְשׁוֹנוֹת שֶׁל מִטָּה בַּאֲלַכְסוֹן אוֹ שֶׁקִּצֵּץ שְׁתֵּי כְּרָעַיִם טֶפַח עַל טֶפַח בַּאֲלַכְסוֹן אוֹ שֶׁמִּעֲטָן פָּחוֹת מִטֶּפַח הֲרֵי זוֹ נִשְׁבְּרָה וּטְהוֹרָה. נִשְׁבְּרָה אֲרֻכָּה וְתִקְּנָהּ עֲדַיִן הִיא אַב טֻמְאָה כְּשֶׁהָיְתָה. נִשְׁבְּרָה הָאֲרֻכָּה הַשְּׁנִיָּה וְתִקְּנָהּ טְהוֹרָה מִן הַמִּדְרָס אֲבָל טְמֵאָה מַגַּע מִדְרָס. לֹא הִסְפִּיק לְתַקֵּן אֶת הָרִאשׁוֹנָה עַד שֶׁנִּשְׁבְּרָה הַשְּׁנִיָּה טְהוֹרָה:
כסף משנה
11.
If one cut off two of the cornerposts of a bed on a diagonal, cut off two of the bedposts by a handbreadth by a handbreadth on a diagonal, or reduced their size to less than a handbreadth, the bed is considered as broken and it is pure.
If one of the sideboards were broken and fixed, the bed is still considered as a primary source of impurity, as it was before. If also the second sideboard was broken and fixed, it is free of midras impurity. It is, however, impure because it touched a support to which a zav imparted impurity. If one was not able to fix the first before the second was broken, the bed is pure.

הלכה יב
מִטָּה שֶׁהָיְתָה טְמֵאָה מִדְרָס אוֹ בִּשְׁאָר טֻמְאוֹת וְנִגְנַב חֶצְיָהּ אוֹ אָבַד חֶצְיָהּ אוֹ שֶׁחִלְּקוּהָ אַחִין אוֹ שֻׁתָּפִין הֲרֵי זוֹ טְהוֹרָה שֶׁהֲרֵי זֶה כִּכְלִי שֶׁנִּשְׁבַּר. הֶחְזִירוּהָ מְקַבֶּלֶת טֻמְאָה מִכָּאן וּלְהַבָּא. הֲרֵי זֶה דּוֹמֶה לְמִי שֶׁעָשָׂה כְּלִי אֶחָד מִשִּׁבְרֵי כֵּלִים שֶׁנִּטְמָא שֶׁהוּא טָהוֹר וּמְקַבֵּל טֻמְאָה לְהַבָּא:
כסף משנה
12.
When a bed had contracted midras impurity or other types of impurity and then half of it was stolen or lost, or brothers or partners divided it, it is pure. It is like a broken k'li. If it was put back together, it is susceptible to impurity in the future. It is like someone who made a k'li from the broken pieces of impure keilim. The new k'li is pure and is susceptible to impurity in the future.

הלכה יג
מִטָּה שֶׁנִּפְרְקוּ אֵיבָרֶיהָ אִם נִשְׁבְּרָה אֲרֻכָּה וּשְׁתֵּי כְּרָעַיִם אוֹ קְצָרָה וּשְׁתֵּי כְּרָעַיִם הֲרֵי אֵלּוּ מִתְטַמְּאִין מִפְּנֵי שֶׁרְאוּיִין לְסָמְכָן בַּכֹּתֶל וְלִישֹׁן עֲלֵיהֶן:
כסף משנה
13.
The following laws apply when the components of a bed were taken apart. If one sideboard and two bedposts or one headboard or footboard and two bedposts were broken, it is still impure, because it can be propped against a wall and slept upon.

הלכה יד
מִטָּה שֶׁנִּטְמֵאת כֻּלָּהּ אִם הִטְבִּילָהּ אֵיבָרִים אֵיבָרִים טְהוֹרָה:
כסף משנה
14.
Even when an entire bed contracted impurity, if it was immersed component by component, it is pure.

הלכה טו
הַמְפָרֵק אֶת הַמִּטָּה לְהַטְבִּילָהּ הַנּוֹגֵעַ בַּחֲבָלִים שֶׁלָּהּ טָהוֹר:
כסף משנה
15.
When one takes a bed apart to immerse it, a person who touches its cords, is pure.

טהרה הלכות כלים פרק כו
Taharah Kelim Chapter 26