Today I was checking my tefillin straps and was painting them where they were not black. Using the kosher tefillin paint, I said “לשם קדושת תפילין” the first two times before I painted, but the third time I said this in the middle of me painting. Is there any halacha of saying L’Shem after touching the straps with the paint, but before you finish the touch up?
The intention was for for Tikkun but not knowing how many spots needed to be touched up?
It is sufficient to say le-shem kedushas tefillin once, before touching up all the spots of the straps. There is no need to repeat the statement for every stroke of paint made on the straps. The general statement of intention is sufficient for all the “touching up” that follows.