Brion As you suggested I ran the numbers with The Complete Riggers Apprentice using the curve for LWL for the ODay 35 (single spreader) and the wire size on the boat. The designer, CR Hunt, has not gotten back to me yet on the RM30. What I got is tuning at 20% breaking strength for the uppers I would be at 52% (or 1980/3780) of the shround load, and tuning at 12% BS for the lowers I would be at 36% (or 984/2730) of the shroud load. From that perspective I don't see a problem unless you tell me different. I ran some more numbers inregard to their comment in the manual that the wire was oversized. For the current 9/32 wire size on the uppers the safety factor is 3. If I would drop the wire size back to 1/4 the SF is 2. I think that explains their comment. I am assuming from all of this, and what I make out from your book, that back stay (masthead rig) would have the same kind of margin so that tuning to 20% of BS would be OK. Thanks for your assistance. Good Winds DaveM s/v DAMWEGAS