Reference for Menachot 80:9

ומי אמרינן תעשה ולא מן העשוי (איני) והאמר ר' זירא הטיל למוטלת כשרה

as soon as three fingerbreadths of the garment had been woven!<span class="x" onmousemove="('comment',' As soon as a strip three fingers wide (the minimum size of a garment) had been woven they used to insert two fringes, one at each corner, and the other two fringes they inserted when the cloth was finished. Now it is clear that the obligation of fringes falls due only when the weaving is finished, nevertheless, it is taught here, that the first two fringes are deemed valid and are not regarded as ready made.');">¹⁴</span> - Render: they used to insert the fringes as soon as the last three fingerbreadths had been reached.

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