National 12 - find out more...
 

Could I make a 29er carbon rig fit my crusader

Started by chopper, 21 Jul 2009, 08:17

« previous - next »

chopper

Could a 29er mast be made to fit a 12??
 
regards Paul

John Meadowcroft

Yes
 - If it is too short - there is no minimum so that is ok.
- If it is too long - cut it down to max length, or just done pull the sail to the top as it is the black band that is relevant, not the length of the stick.
- You may need to reinforce sheaves if they need to be moved as there is a rule about the height of the jib
- If the section is too big you could make the deck of the boat wider, conversely if the section is very small you can wrap carbon to make it the right size.
- If it is lighter than the minimum weight of 5.5kg you can add a corrector - do the same if the centre of gravity is too low.
- It may be too stiff - not stiff enough.  I anticipate that a lot of sideways stiffness comes from the trapeze - which you would need to dispense with - whilst from memory they have a lot of fore and aft bend so you would probably need a suit of sails specially cut for it.  It is also clealry designed for a kite - this may also have some impact too.
On balance whilst possible you would need to develop a suit of sails to work with it and that would negate any cost benefit of buying it
Jo Richards could probably make it work - can you? [Notably the mast section is one of the few standard items that Jo uses....]

Ian (Guest)

I guess you could but I'm not sure that you would want to.
The 29er rig is a three peice ali mast with only the top section made from glass. Its heavier than most 12masts I've felt and has  fixed spreaders that will almost certainly be in the wrong place., especialy as it was designed to be deck stepped and so everything would wind up to low when keel stepped.
Ian

Jeremy C

The 29er spreaders are not only fixed, they also hold two of the mast sections together with four ss bolts screwed direct into aluminium. this quickly leads to corrosion and also compression in the mast. With the sort of rig tensions put on a twelve even if the spreaders were in the right place I couldn't see the mast lasting very long!
 
In my view it is the worst mast ever made! very agricultural- the two main sections are non tapered so would be difficult to control bend and then you have the floppy glass top section - yuck! Now if you had the carbon mast from a 29er XX then you might have more to play with.
Trick Cyclist-3444<br />In the pink-3408<br />Kifi-2431- under restoration<br />Flying Saucer 1277 (joint owner)<br />and now Bart 3455 too (sigh!)

white offspring number 2

You wouldn't want to do that - it would be a real waste of carbon. Stick with what you've got's my advice. Or use an In.t14 rig!
I'm quite happy with my Tasar and 59er. Sunday out in 1 bft. Still got on the plane easily with 155 Kg crew weight.
Take care 12ers and greetings from Julian Bethwaite. He thinks you're a great class - a little crazy but great none the less!
Cheers!
Jim.

Jimc (Guest)

I concur with the "you wouldn't want to" part. I've had a bit to do with 29ers and seen someone experiment with bits from the rig on Cherubs. Its a very effective rig on the boat its designed for, and the whole boat, including the rig is a very impressive bit of production engineering. The challenges in getting the build cost down so that the boat could be sold profitably at a price parents were prepared to pay must have been formidable. But you can hear a big *but* coming. I'll cheat, I'll say however.
However there were, as noted above, compromises necessary to achieve all the design goals for the 29er. In addition very different bend behaviour is required from a skiff type rig with sails that never have to be squared off downwind. All this means that a 29er mast based rig would probably be much slower on a National than an old tin mast rig, and you'd most likely need to have quite a sail development program - several sets of sails or at least recuts to get anywhere near the performance that a standard tin rig will give you.

n12 Bottom Banner