I am purchasing a new pair of Tefillin, after much research (this website included) and consultation (with the Sofer and various Rabanim), I will be purchasing a pair according the standard Ashkenazi Beit Yosef Minhag. The last thing I need to decide is which way have the kesher on the shel yad will be tied: to wrap inwardly or outwardly. To date, I have wrapped outwardly and tied the hand tefillin according to the Nusach Sepharad tradition. Would it be acceptable for me to continue to wrap outwardly in this fashion? Despite having Ashkenaz Beit Yosef Tefillin. Is that a common and legitimate practice? I noticed that a number of people in Israel who have Ashkenaz Tefillin and daven Nusach Ashkenaz wrap outwardly, despite every book and website I’ve read stating that Ashkenazim should wrap inwardly.
ב"ה Shalom A major part of the Tefillin is the way the knot is tied on the "shel Yad". The direction the Tefillin are wound stems basically from the way the knot of the "yud" is tied on the Shel Yad. As I have said in an earlier answer. So you must consult with your Rav how the "kesher" is to be made and proceed accordingly. May you be "zocheh" to perform the mitzvah of Tefilin in utmost adoration.