Seeing as the ten Amos ot the Paroches required five pillars and the twelve of the Masach, four, why did the hundred Amos of the north and south sides require only twenty pillars?
Oznayim la'Torah: Because the former, which were woven from thick multiple threads, were much heavier than the latter, which were made of twined linen threads, and therefore required more pillars to hold them. 1
See Oznayim la'Torah, who elaborates further.
How were the curtains fitted to the top of the pillars?
Rashi (in Sanhedrin, 22a): They hung on the hooks on the pillars via loops that were sewn on to the curtains.
How were the curtains fitted to the bottom of the pillars to prevent them from flapping about in the wind?
Rashi and Rashbam (on Pasuk 18): This was done by a series of pegs 1 with rings attached, round which they wound the bottom of the curtains with ropes, and which they hooked on to the pillars - each pole contained a hook at the bottom.
Six Tefachim by three (Rashi).
What were the 'Chashukim'?
Rashi, Rashbam and Seforno: They were silver strips.
Where were the 'Chashukim' placed?
Rashi: It is not clear whether they capped the top of the pillars, went round the middle or surrounded it like a maypole. 1
Seforno: They went round the middle.
Rashbam: The pillars were surrounded with silver.
This implies that the strips went round the entire pillar (PF).
Why did the Torah not specify the dimensions of the pillars or their sockets?
R. Chaim Paltiel: The Gemara implies that the stated from what is explicit - that all the pillars were an Amah thick, and so were their sockets, 1 like we find regarding the Kerashim.
How can we learn from the Kerashim? They were one and a half Amos wide and an Amah thick, and there were two sockets under each pillar! (PF). We learn from the Kerashim that the pillars fitted plush into the sockets, with nothing sticking out.
QUESTIONS ON RASHI
Rashi writes that there were five Amos between the pillars. Since there were twenty pillars each along the north and south sides of the Chatzer, the length of each side should have been ninety-five Amos. Why does the Torah say a hundred?
Riva citing R. Efrayim: The curtains themselves spanned ninety-five Amos. The combined width of the twenty pillars comprised the remaining five Amos. 1
Seforno, Riva, Moshav Zekenim (in 26:1), Chizkuni (in Pasuk 15) and Da'as Zekenim (in Pasuk 9): The corner pillars are counted in only one direction - for example, the pole in the southwest corner was the twenty-first pole on the south side, but it is counted as one of the ten western pillars. 2
Riva: We must say that the width of the ten pillars on the west and east side comprised the remaining five Amos - those pillars were twice as wide. (This is fine for the west, but not for the east. The Pasuk counts three pillars for fiftrrn Amos of curtains on each side of the Masach. If we will attribute the extra five Amos to the width of the three pillars, they are almost seven times as wide as the pillars of the north and south sides! - PF). See also Sifsei Chachamim and Oznayim la'Torah.
Riva: And the pole in the northwest corner was the eleventh pole on the west side, but it is counted as one of the northern pillars; The pole in the northeast corner was the twenty-first pole on the north side, but it is counted as one of the three pillars for the [northeast] curtains to the left of the Masach ... .