I have done it several ways but prefer to band them. I like the Callicrate bander since it can even be used on mature bulls. I sell bulls mainly so that is the reason for that. I don't want to send a cull bull to the sale barn that hasn't been cut regardless of the age. It works great and not much discomfort (at least that is what they tell me). Just be sure to give them a tetanus shot when you do it. Using a knife is fine if you do it when they are young.
I had a crazy thought when you were joking of the pain , some organizations might jump on this as cruelty to animals, they have done some other crazy things an have got by with it...
They do consider it cruelty. Their version is that we rip out their testicles when they are babies and leave them to bleed it out. Sounds kinda brutal huh? Haha.
With the bander you can do it at any age. Since we sell mostly bulls we do not castrate until we know we want steers. Kinda hard to reverse the process once it is done.