I decided to replace my slightly bent and slightly dented mast with a new one at the beginning of this season. Since then, whenever I sheet in on the main after a tack there is a single cracking sound that sounds like it originates near the base of the mast and more metallic than fiberglass. Yesterday in 15 knot breeze the cracking popping sound occurred repeatedly so I eased the sheet and went in praying the main beam didn't crack before I got home. There was nothing visibly wrong, and no movement felt. Dolphin striker tight. Is there any way this is not an ominous sound? What could it be? Click and Clack are you out there?

My mast makes this sound when it rotates if the forestay is too tight. Loosen your rig a little bit and see if the sound is going away...

hard to say but could it be the shackles holding the stays to the mast shifting? I hear this occassionally and that is usually what I attribute it to. They can slide a little side to side and I think this is what causes it. I put spacers on and seems to improve.

I second that - it's probably the shackles at the mast hound flopping from side to side. The mast really translates that noise making it sound like it's coming from somewhere else.

I put spacers on all my shackle pins at the hound to keep them centered and from flopping to one side. No more noise.

the sliding is also bad for the hounds - it can cause them to fail over time.

If your mast has diamond wires with the turnbuckle in the front of the mast, it could be the turnbuckle going from one side of the mast to the other after tacks.

The sound was occuring many times per minute on the same tack when I became concerned and went in. I did put about 1" of pre-bend in the mast so the diamond wires are certainly tighter than on the old mast that was bent on the short axis. The diamonds attach on the side. I keep the shrouds and forestays a little loose because I am too lazy to tension and detension the rig every weekend (mast-up storage obviously). I appreciate replies and suggestions.

I have had similar noises before and found a good amount of SailKote to the ball and base before rigging stop the noise.