I am a do-it-yourselfer too - except a few things need experience, tools and are not economic to do myself. 

Cutting bull calves and preg checking cows both fall into that category for me. My vet doesn't charge much to do either job. He has a couple tools that he uses to slit the sack and nip the bottom off so it drains. I have never had an infection problem after he cuts them.

We cut at spring workup rather than weaning.  Nice thing about cutting is you can look down and count to two and you know you got them. My cut 1 to 2 month old calves seem to heal quickly and are running around as always in a few days.

Jim at Dawn