If you're ever in a pinch for spring clamps, reader John Larson advises making them yourself from short sections of PVC pipe.

If you're ever in a pinch for spring clamps, reader John Larson advises making them yourself from short sections of PVC pipe.

One of his more interesting builds is his series on building rocket engines out of PVC pipe written in conjunction ... larger rocket engines out of 2 or 3-inch PVC may not make much sense due ...