Springstay location question

[Brion Toss]

Hi again,
Hard numbers would be better than I-think-that's-enough-angle at this point. Height up, distance out, and distance forward will give us our vectors. Could be time for a consult, if you don't want to work those numbers yourself.
Fair leads,
Brion Toss

[mariner2k]

Hi, I'm not sure what to make of the angles I calculated regarding mizzen lowers.
If you were to consider the distance of the shrouds forward of the mast as a plane, the angle would be just under 5 degrees.(X two shrouds) The angle from the mast to the actual chainplate is just under 9 degrees. Two questions arise:

First are these angles adequate?

Second, a more general question, does the fact that there are two forward lowers as opposed to say one straight forward(theoretically resembling a baby stay) make up for what appear to be shallow angles?

I do also have the fittings and a chainplate astern to add lower intermediates if necessary. Also,it is a deck stepped mizzen.

[Brion Toss]

Hello again,
Those are steep angles, in both planes. You can likely improve the forward lead by moving the chainplate forward -- you just have to stop before you interfere with main boom swing. But the lateral angle is a bother. Just to humor me, would you share the numbers you based those angles on?
Fair leads,
Brion Toss

[mariner2k]

And humor you I shall! On one of the angles I plugged in the wrong value. On the other I took a more careful measurement and the angle was actually a bit less.
So the angle from the mast to the chainplate turned out to be 14.5 degrees. The angle going on a forward plane is only 4.09 degrees.

Numbers are as follows:

Mast height to connection is 286"
Center of mast to where chainplate meets the deck is 74"
That angle should be 14.5 degrees at the top.

On the other:
mast height to connecter is 286"
going directly forward is 20.5 inches.
That angle is 4.09 degrees.

Disclaimer: I haven't done this in a few (35+) years I could be wrong.

Would I be correct in assuming that lower shrouds aren't design or located to support a mast fore and aft with any significance?

Thanks, Kevin

[Brion Toss]

Hi again,
On the one hand, you have a huge lateral angle; you could take the forward shroud tang up to about 30ft. and still have 12 degrees. On the other hand, the forward sweep would be negligible by then. So you could only get your forward intermediate (or a more effective forward staying at the current height) by moving the chainplates forward. Say, to about 4ft. or more forward of the mast, assuming that the shroud would not then be in the way of the main boom.
Fair leads,
Brion Toss

[mariner2k]

Ok, bearing in mind that the point of this exercise is to be able to fly a mizzen staysail. The double backs on the main can be dealt with when I change masts.
Assuming I can't move the lowers forward 4' (though I will check), I'd like to back up a bit.
My old ketch had a springstay opposed by running backstays on the mizzen cap. I know how you feel about springstays but could this be a do-able option?
Or settle with flying a small staysail from just below the jumpers, which would puts me around 20' from the highest deck.
Why would a builder design a ketch without the ability to use a staysail? I assume that there is a reason for that configuration.