[Joe Henderson]

Dear Rock,

I have never seen a stay fitted with a bobbin thimble even come close to jumping out when the mast, inevitably, "whips a bit".

The seizing is in the same area that a normal seized - in thimble seizing is positioned, and ensures that the legs of the eye are no more open than with a normal heart shaped thimble.

Remember that bobbin thimbles are formed exactly the same as normal solid heart shaped thimbles ( which are sized and made to take a pin ) up to about 100 degrees each side of the crown and the line captures the bobbin in such a way that it is impossible to pry the thimble out of the eye.

Think of them as solid heart-shaped thimbles with 75 percent of the point cut off.

The clearances in the jaw and on the pin are snug, but not overly so, just the normal working clearance I would require for swaged or StaLok eyes on wire.

Clearance in the jaw, and in the upper tangs, has no effect on the security of the eye.

I have seen many seized-in, and both hand and machine spliced heart shaped thimbles that were slack up around the points with the thimble cocked-over in the eye, it would be difficult to pry those thimbles out of the eye too, but I have never seen one fall out in service.

You need a beefy rigging vise and the correct tools and materials to apply seizings that are reliable, long lasting and up to the task.

Regards,

Joe,.