Oke, my mig tip can't be moved so i shortened it, only i shortened too much so i had to reduce the air flow to get it running constant instead of pulsating.
But it was after some tweaking still not hot enough, then i ran out of "play time" i will give it another try tomorrow . The advantage of having to restrict my airflow is that I now can adjust it, see photo with the valve i attached.
I have searched for smaller tips at work but the smallest is the one I have.
Yes the bricks are very hard, it is almost impossible to drill through (luckily i have a waterjet at work) what is a long time to heat up? i have no idea how long it should last to heat up approximately. I have the feeling i am coming very close but still not there yet.
So if i understand correct a neutral or even lean flame is hotter the a rich one, that is good to know, so i can even run it even a bit lean to get to the higher temperature.
Thanks for the advice,
I will post my progression tomorrow (i hope)