Product review (3 stars): Thanks to those that had the idea of using the ...
Thanks to those that had the idea of using the 3/8" lock washer.  It works perfectly and saved me a bunch of money or having to resort to cheaper knobs.  All 5 of my knobs were cracked but i still had the little metal inserts that were with the original knobs.  Here is a video I uploaded to YouTube of the basic process.  Hope it helps.

https://youtu.be/sdKvrFtV878