The purpose of the dolphin striker is to change the front crossbar from a simple beam in bending to a truss such that all of the elements of the truss (crossbar, dolphin striker post, dolphin striker rod) are either in pure tension or pure compression - bending loads are eliminated (in the vertical axis). Since these items are much stronger in tension/compression than they are in bending, this allows the front crossbar to be significantly lighter AND stronger than it could be if it were just a simple beam.

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You are quite right to show Arjan and this forum the truss-model.

But you forget to mention that in this model all the elements are theoretical connected "unjerkable" together.
Which isn't true ofcourse in real life.

So, in our dolphin striker all the vertical downforces are lead, no better, diverted to the bolts on the side. And these are not unjerkable.

There are a lot of catsailors amongs us who don't realise that these almost hidden bolts ,underneath the frontbeams in the dark corner close to the hull, are the key elements of the whole sturdy dolphinstriker. And therefor also the weak element!

With regard to your remark about the weight profit because of the truss-concept, I like to point out that the frontbeam (and aftbeam) have more loads to deal with than just the compression load of the mast.
They also hold the hulls together and therefor have to withstand a fairly high torsion load by the hulls.

For that reason most modern cats don't use simple single aluminium pipes or profiles anymore.
They all have special designed separate inner profiles to withstand the load which a cat with two hulls brings on.



P.S. for all these reasons I made my cat with no dolphinstriker, but with special constructed beams (of wood! and carbon). And they hold (knock wood!) already three years in high seas!

Thanks again guys! I realy love this forum... Lots of info for free :-)