What do you actually do to cut the head off a bolt?

[PlywoodPascal]

Newish to home mechanicking but have done several small jobs now after starting with changing g my own winter wheels a few years back.

I am now trying to remove a body panel from my car but there are loads of seized bolts or ones that just spin their fasteners too on the other side…

I’ve bought a dremel (they are in tricky spots)

But….

What does cutting the head off a bolt actually involve… how do you do it, where do you cut, what do you do, basically?

[Super Sonic]

First and most important Wear Eye Protection! Then it's a matter of access, cutting away where you can until there's no bolt head left. This does leave the problem of removing the bolt thread though...

[E-bmw]

As above the general idea is to hopefully leave the shank/threaded stud etc untouched so that the thread can be cleaned up and re-used.

Obviously sometimes this isn't the case and all will need replacing.

There isn't really a hard & fast rule, just do what you need to do without going straight in with the nuclear option of cutting the lot off.