There are very few safecrackers around, whatever Hollywood might suggest.
Most safes which have attracted the attentions of criminals are carried off and attacked with power tools, in private, over a period of time.
Today’s invention is a coating for safes which consists of irregular, steel protrusions, welded on the outer walls and roof of a safe. These resemble the broken bottles one sees on the top of walls…a major disincentive to even the keenest crook.
Only the keypad and handle would be free of the blades.
Such an approach makes any manhandling of the strongbox (which would be required to get it down stairs, out a window or into a van) almost impossible.
Even wrapping a mattress around or hammering planks onto the blades it would be hazardous, since they would be liable to pierce any such protection when being moved. Anyone foolish enough to attempt entry using explosives would create a cloud of shrapnel.
There would have to be a special system for transporting this from the factory (without massively increasing the weight). You could attach the blades at the destination, but that would introduce vulnerabilities. I’d advocate something like a unique, hard rubber mould for each side. This would accommodate all the blades on one side, sheathing them perfectly, and also provide four circular segments which would allow the safe to be rolled to position on its side as a cylinder -only then removing the segments from the sides. Criminals would find it hard to make such a set of sheaths for a given safe without access to its precise blade geometry.