Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 9 · Vastu, Griha Pravesha
वास्तु गृहप्रवेशश्च
शंकुं त्रिधा विभज्याद्यं चतुरस्रं ततः परम् ।अष्टास्रं च तृतीयासौ मन्वस्रं मृदुमव्रणम् ॥ ५७५ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 575.
Divide the peg into three parts. The first is four-sided. Then comes an eight-sided part. The third is 14-sided. It should be smooth and without flaws.
Simple meaning: Make the peg in three parts: four-sided, eight-sided and 14-sided. It must be smooth and flawless.
एवं लक्षणसंयुक्तं परिकल्प्य शुभे दिने ।
Make the peg on a good day and set it on ground marked out with the thread.
मृदुध्रुवक्षिप्रभेषु रिक्तामावर्जिते दिने ।
Choose a good star and a good weekday, avoid empty days, and keep the 8th house free of bad planets.
नैधने शुद्धिसंयुक्ते शुभलग्ने शुभांशके ।
Set the peg in a good rising sign, with a clean 8th house and good planets looking at it.