#1 2011-02-24 20:06:53

Registered: 2011-02-24
Posts: 339

V800/V26/F26 - Rigging and Pointing ability

[Moved from 'Technical Advice' pages, dated 14/02/05]

The advice given here is supplied by Ian Powell who owns and sails "Much Ado", a Victoria 800 with cutter rig, on the River Crouch. Ian initially replied to a query raised by Colin Deuchars at the beginning of the 2004 season. Colin's boat, "Erica", is a cutter-rigged Frances 26 and so, not directly comparable with "Much Ado". We start with Colin's original question.

"My Frances 26 cutter seems to have a lack of pointing ability. The sails are old, although in reasonable condition, a little baggy maybe but not so bad as to cause a major pointing problem. There is no traveller fitted and the cutter rig will be less efficient than the sloop but I should out-point a Centaur. I can only get about 100 degrees to the wind! This seems to have been a problem only in the last season. The mast set-up is no different from the previous year. Can anyone offer any suggestions?"
Colin Deuchars - 21st April 2004

Colin received no immediate response and we don't know how he fared during the season but, in the autumn, Ian made these observations.

"I notice that Colin Deuchars seems to have essentially the same problem we had, although he doesn't say how the weather affects his lack of pointing ability. Slack rigging and baggy sails might actually be an advantage in light winds but as the wind rises they become more and more of a handicap. Our sails are certainly not new any more but our windward performance increased dramatically as we tightened up the rigging screws. Colin's sails are not going to stretch more whilst in storage so his problem is unlikely to be the sails. A traveller would undoubtedly help but as he has never had one it cannot be the cause of his problem. The only thing that has been changed in any way is the rigging. It has to be undone to lower the mast and then retightened. The question has to be asked, 'Is it really exactly the same as it was last year?'

Bob Hathaway describes setting-up a fractional rig F26 in the Technical Manual but the requirements are almost the same. A bit of pre-bend in the mast (bowing forward) is desirable in both masthead rigs and fractional rigs, and a taut forestay is always a prerequisite for good windward performance. Just like a fractional rig, our inner forestays need the lower backstays to be set quite tight. To get the outer forestay tight, and to induce a bit of pre-bend, the main backstay also needs to be quite tight. To balance all that, the lowers need to be a bit tighter than the 'dangling loose on the lee side' that masthead rigs can get away with. We've currently got a bit more than half a diameter of pre-bend and the shrouds are 'on the edge of loose' on the lee side. As a result she points higher, sails faster and she is more stable - and the more the wind blows the more noticeable the improvement. We're still experimenting so we'd really like to hear from someone with more experience at this."
Ian Powell - 7th November 2004

Ian reported further on this subject in mid-December.

"I thought you might be interested to hear that we've continued tweaking our rigging and we now have proper stress measurements of the results. The usual advice is to set all the rigging at 10% of breaking strain for cruising and 20% for racing, but realistically 10% wouldn't be very efficient in anything more than light winds. With a fair bit of trial and error we've found the best results so far with about 12% for the main backstay and 15% for the lower (staysail) backstays."
Ian Powell - 16th December 2004


Board footer

Powered by FluxBB