Sorry, 7000 should have been 1700 pounds. I always hate it when I sound like an idiot, even though my wife says I have a habit of it.
Blaise
Blaise, I kinda thought that sounded excessive. My engineer brother always seems to come up with
phenomenally high stress figures for the rig. He figured our Raider 33 upper shrouds were loaded to 12,000. I said, the boat only weighs 9600! And what happens when shrouds get overstressed? - the boat heels over! I mean,
duhh! - the water always yields, spilling off the load, so there is your friend. You can't stress the rig to breaking point unless you can keep it under full sail, under heavy conditions, and fully upright, to pose the maximum resistance to the load. And you've got to be either a complete cluck or a sorcerer to actually do that.
As a simple rule of thumb to gauge practical rigging stresses, look at the series of running-rigging blocks the manufacturer provided with the boat.
Schaefer '03' = 1000 lbs.
Schaefer '05' = 1500 lbs.
Schaefer '07' = 2000 lbs.
If that's too tricky for you, look at the size of the rope or size of the clevis pins - corresponds to the blocks.
'03'-series = 3/8" (3/16" pin).
'05"-series = 7/16" (1/4" pin).
'07'-series = 9/16" (5/16" pin).
I rigged most of my H25 with '05'-series, having calculated most of the sail loads at around 1250 (max). That would suggest the excellent '404' series, no longer made. I use '05'-series for sheets, halyards, and deck cheek blocks. I have a couple of '03'-series, mainly for reef and outhaul lines.
Anything you can't inspect easily (spinnaker-halyard block) or have any question about: scale up. Anything with more than a 90-degree bend: scale up (my foot blocks are '07'-series). Also, remember that wire rope sizes at one-half running-rigging sizes are way oversized for the actual loads. In general, you're in safe hands to load anything to 1/2 or 2/3 manufacturers' rated load, all other things being up to the task.
The next question, of course, is if the attachment points on the boat are up to the task; and gauging that is my stock in trade; but I'm here to provide the best general guidance I can without me charging you money or you wanting to sue me.