I'm glad that I watched your video because I see that even with the magical tool you can still break off the bolt or stud.

Not my project but when he snapped that bolt I had that pucker sensation

Not sure why your heating the studs. Its expanding inside the block which makes it harder to remove. Take a torch and warm the block around the studs

Continuously torquing the stud in one direction while it is near red hot is sure to fail as heat is softening stud , heat it as near to the block as possible and allow it to soak in to the threads and rock the stud gently in both directions to try and clear some rust from the seized threads. A few hard blows to the end of the stud can help break it loose. The welder trick is the best choice if you have the tools . You could even cut the stud off about 3/8" from the surface and place a larger hex nut over it and weld it to the stud , the heat transfers very quickly right where you want it , this works great , if this does not work you are drilling and tapping anyway.

metal expands as it gets hot. so you are expanding it into the hole.. you need to heat it up and then cool it quickly to make the stud expand and contract to free it up

This can also be done with a tig welder if you don't care about a certain tungsten or if you dedicate one to contaminate on stuff like this. A big tap with a 2 lbs hammer on a punch held with vice grips on the siezed fastener then a quick blast with the tig torch then a penetrating oil after it cools a little. An impact driver used carefully can sometimes help as well. That said...I've really wanted one of these heaters.

always turn a stuck bolt both ways before removing...firm taps with a hammer can also shock the corrosion bonds in the threads... heat is great but the two tips on left should always be done.

I miss those induction heaters, need to get one ASAP!

have you tried this on o2 sensors?

I remove broken bolts with mig welder, it the easier way. Drill a small pilot hole in the broken bolt, start the weld in the hole, and build it up until you can get a large (new) nut on it. Fill the nut with weld pool to the top, , usually come out easy, sometimes I have to repeat with new nuts if it keeps breaking loose. I would not drill and tap unless you make a jig or use a drill press to keep the drill centered and vertical. I've also done it with a stick arc welder using 1/8 rods. Try using a nut twice the size of the one that snapped off, it allows more weld filler and gives more leverage. This one was snapped off below the surface and took 4 tries with bigger nuts each time. kzfaq.info/get/bejne/ebWghayHrM-4oaM.html

You do not obviously know how to deal with rusty items like the gentleman said heat the area around the bolt I live in the rust belt actually on the east coast all I deal with are rusted nuts and bolts 24 and 7 while I'm fixing cars When you live in an area and rust you are not just an automotive technician who takes things apart you are a corrosion and rust expert You have to develop certain skills and techniques to work these things to avoid breaking bolts constantly otherwise you would never get a single job done Otherwise that done cool tool thank you for the demonstration

Good tool in wrong hands