Is my main sail sheet rigging OK?

[thunderhoof]

One reason to have three blocks on the boom is to spread the load so all the force on the boom is not at one point to reduce the chance of a shock overload breaking the boom. This design is often seen in mid-boom sheeting.

You might try eliminating 2 falls at the center blocks, reducing the purchase to 6:1. This should be sufficient for a 27 ft boat.
Is there a traveller on the cabintop? You might consider one of good design for two reasons. The first is to allow you to center the boom when going upwind in lighter air; the second is that it is easier to release the traveller cam cleat compared to the mainsheet cleat if you are suddenly overpowered.

[TrentePieds]

Right you are, Jim — knowing what you know, it'll not surprise you that I left those things unsaid quite deliberately. My not speaking about them is not, as you surely know, tantamount to my not knowing about them :-)!

If you can handle your sheet loads without mechanical help such as winches then you can certainly also handle those loads WITHOUT that help. You will also agree that I spent some time pointing out WHY the loads in a 20 knot wind are SUBSTANTIALLY less than in a 30 knot wind. You MAY agree — though that is less certain :-) — that with my usual propensity for crediting our cruising friends with some native nous, I left unspoken the possibility of reefing only because I didn't wish to elicit an "Oh, for gawd sake!" kind of comment. Ultimately the purpose of posts such as these is to help our friends to think through these things, constructively, in their own way, for their own boats :-)

So to tidy up a bit: The T37 sails on her headsail I'm sure. I've not actually sailed one a T37, but in some ways when you've sailed a one-tonner you've sailed them all. In a beast with a high aspect ratio rig such as this I suspect that at 12 knots or thereabouts, I'd have come down from the genny to a 90% jib. At 18 I'd be down to a 50% jib. and a single reef. By 22 I'd be down to the 50%-er and a double reef. But that's just because I'm such a coward :-)

So s'posing double reefing the main leaves you with 150 sqft of main ( REEFED "P" being 30ft out of 42 and REEFED "E" being 10ft out of 12) then the main sheet load in 20 knots would be 90 x 3/5 = 54 lbs, in 30 knots, something in the region of 120 lbs.

As you also know, these figures are "good enuff" figures. Spurious accuracy is the bane of sound, practical calculations.

Cheers :-)

TP

[Drinky Crow]

Does this run on ball bearings?



'cause,.... can't tell from website.