To store a carpenter's square, nail either a 13-in. or 22-in. length of tongue-and-groove flooring to your shop wall, groove side up. Then, to hang your square, just drop one leg of the square into the groove of the flooring piece. The length depends on which leg you want to be horizontal.
Water trickling in copper pipe can make soldering a joint almost impossible because you can’t get the fitting hot enough. Stuffing a wad of bread into the pipe will absorb the water and you can get done before it dissolves. But use white bread; whole grains can get caught in valves. Before turning water back on, temporarily remove faucet aerator.