Adjusting the height –
If the floating selvedge isn’t high enough in the shed for the shuttle to go under it easily, raise the threads by tying loops of string around them and attaching the loops to the castle of your loom. Raise the loops so the floating selvedge threads float in the middle of the open sheds as in the photo.
Adjusting the tension –
Since they don’t interlace with the wefts like the main weave, they are likely to get looser as you weave along. You can hook a weight on each one and let it slide along as the warp is advanced as in the photo. Because they don’t get tighter as a rule, they can be beamed on with the regular warp ends.
If you used separate threads for the floating selvedges, they must be anchored at the back of the loom in some way so there is tension on them for weaving. The next post will talk about how to know how much weight to add.
I love this idea for winding a selvedge thread. I learned it from the participants in a workshop I taught years ago.