Masts

Originally posted by JimC Originally posted by tack'ho In fact utimatley if you could build a unstayed mast light enough and stiff enough and control the degree of flexibilty over the length and in the desired planes well enough, you can get rid of your stays. Sadly suitable quantities of the appropriate specification of unobtanium are proving tricky to source... I think I've seen 4 attempts at unstayed rigs in development singlehanders in recent years, and the score is three definitely not competitive and one possibly competitive... None have demonstrated an advantage. Of course that's not to say its impossible. To my mind no-one has yet come up with what I regard as a really advanced modern single sail rig - or any non-spinnaker craft. The new Byte rig is certainly a big improvement on what was there before, but I an yet to see an advance I consider equivalent to the prebent flex top skiff style rigs for two handed spinnaker boats. Of course those rigs suffer from the big disadvantage that they are rubbish with the boom squared off... The rig for spinnaker free craft is a very big design challenge indeed.

As I know you know, but others possibly don't, the NS14 has sliding shrouds so that the leeward one can be let forward on a run. Coupled with a fully battened square head mainsail, over-rotating wing mast (often with tapered carbon tip) I reckon that makes it a fairly advanced non-spinny rig.

PS Tack'ho - that is Dan's own design Punk. 

Originally posted by tack'ho mmmm yer I could have a telegraph pole...sorry streaker rig (who if only they weren't constrained by class rules could have a better section carbon mast) and go slower...(ooo yer and they could have a plumb bow as well to maximise waterline length,  and go really narrow, and have foils....damn those class rules!)

Nobody said that the class rules should be changed to allow other rigs - only that there are no classes where both options are allowed and unstayed rigs have proved competative.

 

Originally posted by tack'ho In fact utimatley if you could build a unstayed mast light enough and stiff enough and control the degree of flexibilty over the length and in the desired planes well enough, you can get rid of your stays.

IF? Well thats the challenge, isnt it...

you cant have a sleeve sail on a boat with spreaders and shrouds etc, that is the main problem, well not one that you can take down without the whole mast being taken apart.  Sleeves should in theory be more efficient though, just more awkward having to take the mast out all the time especially on boats which keep their mast up in the dinghy pound.

Wing masts are the attempt at making an efficient mast that works like a sleeved sail without needing to take it down all the time, mainly depends what type of boat its for.  Some sleeves have zips so they can be taken down for example but this still cant get round a set of spreaders!

Originally posted by Guest#260 I thought it was a great innovation and it was a shame the ratings knobbled it

It wasn't much of an innovation - more an attempt at a rule cheat. The idea was to have a mast that rated as a very long section fixed mast (ie lots of drag) but twisted so that it behaved much more like a rotating mast drag wise. They hoped to get a rating allowance for much more rig drag than was actually present.

The measurer, quite correctly according to the rules, elected to give it a rating partway between a fixed mast and a fully rotating mast, and as a result the owner threw his toys out of the pram and went off in a huff because he'd spent a fortune on this stick and was no better off rating wise than if he's kept a standard one.

That particular rating rule aspired to do exactly that - rate any innovation on the exact effect it had on boat speed. That's the big difference between a measurement handicap rule and a box rule.

Edited by JimC

Originally posted by laser193713 you cant have a sleeve sail on a boat with spreaders and shrouds etc, that is the main problem, well not one that you can take down without the whole mast being taken apart.

The Moths seem to manage just fine...