I have a mystic venom boom not sure of the size but I use it for my 5.8m - 3.2m sails. I noticed the clamp has an obvious 'crack ' in it when I had it rigged recently..On further investigation it closes up when there is no pressure on the clamp ( unrigged) and is where a join is in the part that wraps around the mast. I don't think it is a critical part but want some opinions..I've been using it like this for a while and it seems to work ok although I got a bit nervous yesterday and didn't clamp it tight enough and it slipped down a bit..



The crack open under load


The other side not open..


closed up - not loaded





Should I worry or not?

pefectly normal. All these style boom clamps have that bit in two halves. Nothing to worry about

Phew.. thanks..

Some booms like that are "fixed" at the front them seem to be forced open to get the tube in, then bolted together. When replacing these clamps on a mono boom (one whole ally tube - no joints) I have found it very difficult!

If it is opening up check to make sure the bolts are tight enough (the bolts that keep the whole piece together).

Ok. I'll give that a check too.

I think it's like that to accommodate the bend in the mast, that's why it opens up when clamped to a down hauled mast, but closes up when not clamped.

its just the pressure of the rubber mast sleeve compressing in the centre and not on the outer edge, but its normal

Thanks everyone. Glad I posted before I went out and bought a replacement..