Dolphin Striker- Cosmetic Only?

[max mariner]

Is the dolphin striker really needed or is it mostly cosmetic if the bobstay is sufficiently tightened? What advantages does a dolphin striker/martingale give a boat?

What, you ask, is a Dolphin Striker? don't feel bad, i had one on my boat for almost a year and didn't know the technical term 'dolphin striker' until very recently-

here we go:

a short, perpendicular spar under the bowsprit, used for strengthening the bowsprit and jib boom against the force of the headstays, also known as a martingale

Yesterday, while balancing my Formosa's Mast's and tuning the rigging the 'loosened' dolphin striker plummeted to the depths ...hey, i tried diving for it but the water was very murky and very cold...lake superior in May is still COLD.

While searching for other formosa owners online in order to get a measurement for replacement, i came across several other formosa 41's that did not have a dolphin striker.

got me thinking, maybe i don't even need it as long as i can tension the bobstay.

input?, advice?, ..anything please...

Max

Duluth, MN

[Auzzee]

Hi Max,

I cannot imagine the rig designer opting for rigid rigging where it is not needed. I had a martingale on a 36' ketch and considered removing it because it was always getting fouled on the mooring buoy. Loosening it by undoing the bottle screws by a half dozen turns each, soon told me that it was the wrong thing to do when the wind blew hard against the furled headsail.

If the boat has been designed for a two or three point spread, I think the abandonment of the dolphin striker will place you in jeopardy in poor weather conditions. If it was my decision, I would not fully tighten the rig until after retrieving and replacing the currently submerged item.

On the Formosas with a sprit only, I would expect the builder to have strengthened and lengthened the internal section of the spar and to have substantially increased the strength of its support.

Cheers

David

[max mariner]

David,

Thank you for your prompt reply. Great insight there.

In the last two days I have been piecing together a new martingale. I have a Stainless pipe and a fitting that i think will work. tomorrow i intend to install it, see how it goes.

Fair Winds,

Max

[redbopeep]

Originally Posted by max mariner

Is the dolphin striker really needed or is it mostly cosmetic if the bobstay is sufficiently tightened? What advantages does a dolphin striker/martingale give a boat?

The dolphin striker/martingale does for the bowsprit what the spreaders do for the mast. A wide boat with a short mast doesn't need the spreaders and a skinny boat with a tall mast will. The striker is used when the angle of the stay wire is too small with respect to the bowsprit given the size of all system components. The bobstay's job is to provide a tension equal and opposite of the forestay so that the forces on the bowsprit only push the sprit directly aft (not up or down which can break the sprit and isn't good for your furler either). The old fashioned round bowsprits if tensioned correctly literally floated in the gammon/cranse irons while pushing hard up against the bits at their tail end. The striker simply changes the angle of the bobstay wire/chain to improve the loading of the bobstay. You might do without the striker IF your boat doesn't have a huge overhanging bow and if you beef everything else up (bobstay iron, bobstay wire/chain, etc) to the appropriate size given the new angle without the striker. You'd have to do the engineering work. Thus, easier to just replace as you seem to be doing.

From John Leather's Gaff Rig Handbook:

"The martingale or bowsprit spreader is now rarely seen. It came into common use in yachts about 1893-1894 when the new-fashioned and cut-away bows, such as are still in style, were introduced and the resulting poor lead of the bobstay caused the loss of a great many bowsprits in the big racing yachts. The martingale was a steel rod usually fitted to the stem, often on a pivot bolt and led down to bisect the angle between the bowsprit and the stem profile. Its lower end usually had a U-shaped crutch over which the bobstay passed and was retained by a pin. The martingale was stayed transversely by wire shrouds shackled between its lower end and the outboard ends of the bowsprit spreaders."