You now have a stripped feather ready to cut to size and use. I will show this later.
Now for the slow and more difficult way, but better because it leaves a stronger base that will aid in holding your fletching straight on your arrows. First with a sharp knife or box cutter split the feather in half down the crease. If your wife has one of those fancy rotary cutters used for cloth then slip in and steal that thing, just don't get caught! Those would work great for this, my wife don't have one, they are sold in fabric stores but pretty expensive. I'm using a knife.
Now with a box cutter I am trimming the hard quill down a little. Careful; I have destroyed too many doing this, that blade will get in the hard quill and run right into the feather if you don't go slow and careful.
I invested in a few of these feather choppers through the years, mighty handy item. In the old days I had to lay them on another feather and cut them out with sharp scissors.
Now lay your feather in the chopper with the base against the lip in the chopper. Read the caution on top first, or count my fingers in this picture. (Kidding) ease the base closed slowly and carefully so you don't get short fingers. I ease it down and lift a little while pulling the feather against the base. You might ask your buddy to hold it but he may not cooperate.
Once you have it in place and have checked to make sure it has not moved from its bed as they often do, you give it a good whack with the rubber hammer. Experience will soon teach you how hard you need to hit it to get a clean cut. Be sure it's on a good base and not on your Spongbob table.
It's midnight here and I got a Dr appointment in the morning so I will continue later.
Very excited for this, thanks Carp! Been thinking of paying my local bow shop to feather fletch my arrows, but I have a few turkey and goose-hunting friends who can hook me up. I just had no idea how it worked!
Now you probably don't own anything this fancy but I do. I made it from two thin pieces of metal; actually mine are old cabinet scrapers and a hinge. Just something to hold the newly cut feather.