It’s fairly rare that a customer asks me not to tie the first knot on the tzitzit too tight. That’s why I was surprised to see this note a customer added to an order for a white-on-white Beit Yosef talit.
Please see that the tsitsit be tied on both tallitot to have flat corners. That is, that the first knot is not so tight that it crumples the corner more than just a very small amount. I was told that they tied the first knot tight to prevent movement of the strings around the corner of the garment. However I am a little particular about the corners and personally I think the stiff corners of the Beit Yosef prevent that. Thank you, Dean.
Dean is actually quite right, but the truth is we would have done the same even without receiving the request.
There is a halacha, mentioned in the Shulchan Aruch, regarding how tight to make the first knot of the tzitzit (O.C. 11, 15). On one hand, we want the tzitzit to fall along the side of the tallit so that it hangs right alongside the corner when worn (“notef al hakeren“). If that first knot does not keep the tzitzit snug alongside the tallit, they are liable to make their way around the corner to the other side, so that when worn the tzitzit hang from the bottom edge parallel to the ground, rather than the fringed side.
On the other hand, if you make the knot very snug, according to some opinions, scrunched up fabric does not count when measuring the distance from the hole to the edge. The minimum distance is about 4 cm. The hole is usually positioned 5 cm away. So if you bunch up the fabric too much, according to these opinions the tzitzit are not considered attached to the kanaf.
Notably Lubavitch has a very innovative solution that allows them to have their cake and eat it too: They don’t scrunch up the fabric at all, but add a second hole, looping the shamash through it before the first winding, thereby anchoring the tzitzit to the correct side of the tallit.
Those who follow the Chazon Ish bunch up the fabric a lot, and many Sephardim are careful not to bunch up the fabric at all.
Some tallits have stiffer corners than others, which helps the tzitzit stay in place. High-end tallits, such as Chatanim, Hamefoar and Beit Yosef (as Dean notes) feature stiff wool corner patches for this reason. And sometimes decorated corners, notably on Yemenite tallitot, are very stiff.