Gorilla Pod

Step 4: Tap

The 1/4" NPT (National Pipe Thread) tap creates a tapered hole for NPT threaded pipe. In addition to the hole being tapered, the cut thread on the connectors is also tapered. One drawback to this is that, because the tap does not go entirely through the block (although it could), the holes are just a little smaller than the threaded end. This caused one or two of the blocks to crack from the pressure.