Help please - using my mag drill / annular cutter questions

There is a spring loaded pin to center the cutter, used to line up in a center punch divot. Could you replace it with a piece of cold rolled? If you drill a center hole in the bolt and stick the cold rolled into it to keep everything aligned the cutter wouldn't walk around. Another possibility would be to use an end mill in the mag drill first, to make the bolt into a flat surface. You would have to take light cuts. You could also clamp a guide plate over the bolt to keep the cutter aligned.

I'd go at it with a "Flat Cutter Cylindrical" carbide bur in a die grinder to knock down to a flat surface then follow up with carbide drill or cutter. (McMaster)

have had to per drill a 1/4" hole and use the spin loaded pin to hold the mag drill from walking around several times. Just be careful cause she will still want to jump and walk until the cut is started.

How hard can I lean into the cutter to get it started? Obviously the mag base is a limit but can I "kind of wail on it". I picked up a Dremel cylindrical cutter just now and will flatten one off and give it a shot. Only have one shot because if I blunt the cutter, it's a week before I can get them back sharpened.

For the really tough ones I've installed a drill bushing in a plate tack welded in position to guide the drill bit. Works for standard drill bits (cobalt) but if carbide it needs to be solid carbide of solid diameter, not the stepped versions that just have carbide tips installed in a reduced shank shaft.
That's not really a job for an annular cutter unless your reboring to a larger size.

Question>? why not just center punch it and use a standard twist drill. Thats what i use for drilling out all bolts. I understand the cutters cut better but for such a small hole just use a twist drill. Also i use a pointed burr to grind a hole in the middle if i cant get a good center punch. But on that small of a hole depending on how far down it is a center punch may be the only option.

Mostly because I want to remove most of the 3/4" bolt rather than just take a small hole in the middle so the cutter is more efficient for that. Plus also I want to get this down so that I'm doing it "properly" the next time. I drilled out the brake anchor retaining pin which is about 8" long with a set of twist drills and I don't want to go through that experience again : ). To be fair though, these broken blade mount bolts are only about an inch and a half long.

Do you have a 2" cutter? Wasn't sure what size they were i thought you werent drilling but a 3/8" hole. Thats only thing bad about annular cutters they are just to short sometimes.

I have a set from 1/2 up to 2", all at 2" long. I bought them with the cheap mag drill. They seem to run alright not that I'm an expert but I drilled out the 3/4 bolt fairly easily (once it started cutting)