Hello, you simply do not have the TNT canon base to work correctly.
THe base is form like the first screen shot. The right ones (could have only one TNT) serve to shoot out the left TNT (they decide the length and the height the left TNT will reach). The left one is the TNT that will attack the objet you want to destroy.
One of the canon I'm proud of is this one (the four left screen shot of a canon). All dispenser are full of TNT. The water is require, also the slab. You may change the obsidian to another solid block (non-transparent), like dirt or cobblestone.
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Hello, you simply do not have the TNT canon base to work correctly.
THe base is form like the first screen shot. The right ones (could have only one TNT) serve to shoot out the left TNT (they decide the length and the height the left TNT will reach). The left one is the TNT that will attack the objet you want to destroy.
One of the canon I'm proud of is this one (the four left screen shot of a canon). All dispenser are full of TNT. The water is require, also the slab. You may change the obsidian to another solid block (non-transparent), like dirt or cobblestone.
I hope I help you