Un-brazing steel.

To 'de-braze' anything, you need a lot of heat. Enough to get the whole area of braze to melt at the same time. Whilst doing this you ned to be pulling the joint apart to seperate the panels as soon as it softens. It's very difficult to do on small pieces, let alone on panel joints. You probably will distort the sheet metal due to the heat.

If you don't do the above you will find that the joint just keeps redoing itself due to the capilary action of the molten brass..


I can't offer any easy alternatives other than cutting it apart

Good luck

It depends on the situation, if you can apply heat to the area without damage it should be ok, to just pull apart if you can supply enough heat over the required area there is actually very little force requires, that said if this is sheet steel rather than structural parts then it will be very soft.. Oxy A will certainly be required...

Theres nothing wrong with brazed joint if they have been done properly (though MOT stations disagree for no obvious reason), is there any way of repairing the sections, what exactly is wrong with them (pics may help)

The stuff is everywhere and very untidy, and I could really do with removing it to get at accident damage around it. I'll try grinding as much off as I can before trying heat I suppose.

Brazing is difficult to weld over successfully, due to its make up, excess heat will cause the zinc to fume, this gas is highly toxic and dangerous to the brain in particular!!!!!
Brazing has to be TOTALLY ground off, because its base metals, which vary from which type of braze it is, both the basic constituents will turn gaseous when welding over it, not to desirable because of the toxicity I have mentioned, and porosity of the weld due to the gasses permeating thru the weld. without seeing the mess you have mentioned its hard to offer a definitive answer, burn it off you will destroy the panel and your brain, grind it off, but make sure its done thoroughly so you can weld to the panel, this also is a problem as braze bonds with the surface of the parent metal at a molecular level, so more of the steel has to be ground away to get good fresh steel,
I can see the best option is tidy it up, slap on some more filler, and forget about ever mentioning it,

Braze clogs up sanding / grinding discs very fast.
Another method, not to be recommended, is heat up and then BLOW off with compressed air. Of course that means molten braze flying around hence not recommended and needs old fire blankets drapped over areas you won't want it to land (as well as skin protection)

paul H