Drewsbow made me a 3"x7/8" out of a Li'l Chopper that mimics the A&A profile.
Those shorter feathers are a bear to do what Rob explained.. but alas, it's the quill width after reading both threads.
I trimmed the skin and nails off several fingers trying to do Rob's method and still got inconsistency.
When I'd push the chopper down gentle to mark the cut on the quill, then use a sharp box cutter to nick the quill there, it worked.
I'd think Charlie's idea to make a "holder" would be simpler than re-trimming all the quills?
Mike, if you're going to all the fuss to split, dye & grind your own quills, the bit of extra work to be sure they work in your chopper seems a small additional time investment... (???)
...but frustration has it's own limits! that ole "straw that broke the camel's back" stuff, eh?