||Each beam shall be 10 cubits long, and one and a half cubits wide.
Eser amot orech hakaresh ve'amah vachatsi ha'amah rochav hakeresh ha'echad.
||Each beam shall have two matching square pegs [carved out at the bottom]. All the beams for the tabernacle must be made in this manner.
Shtey yadot lakeresh ha'echad meshulavot ishah el-achotah ken ta'aseh lechol karshey haMishkan.
||Make 20 beams for the southern side of the tabernacle.
Ve'asita et-hakrashim laMishkan esrim keresh life'at negbah teymanah.
The beams were therefore 15' x 2'3'. They were one cubit thick. According to some, they were wedge-shaped, a cubit thick on the bottom, and one fingerbreadth (3/4') on top (Shabbath 98b). Other sources indicate that they were a handbreadth (3') thick (Josephus 3:6:3; cf. Abarbanel).
(Rashbam), or 'parallel' (Radak, Sherashim, cf. 1 Kings 7:28), or 'tapered' (Rashi).
Others translate the verse, 'Each beam shall have two pegs, [and they shall also] be plugged into one another.' This indicates that on the sides of the beams there were pegs and holes to receive them (Ramban; Bareitha 1). These pegs were 3 3/4 cubits (5' 7 1/2') from each end of the beams (Maaseh Choshev 2:7).
These were 1 cubit long so that they were covered by the bases (Exodus 26:19). These pegs were formed by carving around 1/3 inch (0.9 cm) all around the beam, and a notch twice as thick in the center (Ramban; see note on Exodus 26:18). According to others, each peg was 1/2 x 1/4 cubit (9' x 4 1/2'), and was made by carving out 1/4 cubit all around the beam, and 1/2 cubit in the middle (Rashi; Maaseh Choshev 4:8).
Since each beam was 1 1/2 cubits wide, the wall was 30 cubits (45') long.