Alternative to marvelous Buccaneer 24

lol that must have been slowing you down a lot!

 

Been asked by James Burwick to throw some sketches and ideas around for a Round Britain race 11x11 metre trimaran foiler ... for an English madman but to be built in France ... so here is the main hull, sort of stuff that you'd expect from me - pretty much a big Sid - but not built in bent ply but carbon and high tech stuff.

 

Gary. R-B race eh!.
Thats pretty exciting stuff. Keep us posted with design progress.

 

Very cool! Curious to see how it looks in that size!


Barry

 

it will be interesting to see how hi sech compares with low tech (stressed ply)

 

Lifted Sid's mast on my own; Jacques was up North looking at grandchildren and new farm kittens, Ian offered to help while he polished his immaculate new dinghy, but I thought why not, did it slowly, winch up, tighten shrouds, adjust spanner, hence all the footprints going backwards and forwards. Kind of satisfying though.

 

And on the bright side you would confuse any tracker alive! Haha would love to see details on that mast, rigging setups and sail hook up and such. Also realized in that pic just how shallow that cockpit is, I'm assuming it's a trapeze only affair?

Barry

 

Barry, here is the very old, like 35 years, Flash Harry wing mast. You can see the carbon reinforcing running up the thickest area of the mast and directly under that is the 4mm ply I beam. There are hollowed ring frames at 1 metre spacings plus leading and trailing edge stringers - for the 3mm skin attachment areas and also the 6mm mainsheet track (which you can just see). The hounds fitting is a wooden beak, reinforced with uni- carbon wrapped round the leading area of the mast, with a shackle taking the three shrouds; the female bearing is wood and glass, as is the male bearing; the halyards have to finish on the mast - otherwise you won't be able to rotate it. All my masts are designed and built the same way. Harry's mast is 9.1 metres by 460mm, weighs around 20 kgs.

 

Gary, What do you mean by a hollowed ring frame for the support structure of the mast? Do you have any pics of the said support structure for us to see? Tim

 

Here's a mast I drew up for Captain Sideburn a decade ago or so; you can see the I beam, well, the frames are drawn on 3mm ply, cut out, then you place them all together in a pile and cut where the I beam line is - so you cut them in near half; then you have to drill a hole in leading and trailing section frames and with holesaw, cut out the middle areas to make a ring frame - but leave some material at the I beam connection bases (the ring frames are for your halyards to fit inside - because no one is going to the trouble of making an aerofoil shaped mast and then hang draggy halyards outside) - then you lay the scarfed I beam on floor, glue two fine stringers to each of the upfacing sides (for the skin to get a decent glue area attachment) then glue each leading section ring frame upright to the I beam (use a generous cove) - when that cures roll the beam over (you'll have to support it against a wall or lengths of timber, then do the same thing to the trailing sections. Reading this must be incredibly boring. Then lay on leading and trailing edge stringers, glue the skin on, epoxy everything of course. Cheers.

 

By rings he means like ribs of a wing. That drawing helps it all come together. How beefy does the mail and female bearing have to be to eliminate binding? I kinda had the thought in my mind a fork tounge and ball setup, that way bend wouldn't effect action, but if there's not too much of a problem and incorporated bearing like that is much simpler and lighter.

Barry

 

Barry, not ribs but ring frames.
I put some dry lube or grease in the bearing cup, works fine, no binding.
Actually you don't want the mast to rotate too easily otherwise it will flap when you pass through the eye of the wind during a tack - and that will stop you dead - that is if you have a decent chord wing mast, a small chord mast like say, on a Tornado, no problem. The wing mast needs to pivot but that's all you need. The rigging tension usually keeps enough load on the bearing to keep this in a good compromise. If it flaps you have to grab the spanner and hold it steady, or lock it fore and aft to counter the flapping, then ease it away to the correct rotation angle once on the new tack. You'll know when the wing mast gets towards the correct rotation because the acceleration will be very noticeable.
The shrouds and forestay going to the protruding beak at the hounds allows you to get correct full rotation, like 70-80 degrees for downwind. If shrouds are fixed to the side of the mast at the hounds, then you'll be lucky to get 10-15 degrees rotation - which is next to useless.

 

Gotcha, not sure how feasible it would be, but what if you somehow had a boom incorperated into the mast? Think it would allow more control of rotation? Not built in of course, but more like a part made separate with a saddle then glued on like the boom mount on a carbon mast. Actually typing that out I answered my own question! That would probably induce twist in the mast or action of the mast.


Barry

 

If you have the main sheeting position slightly aft on the boom of directly above the traveller track, then when you sheet on it pushes the boom forward and that definitely helps control. But when you tack, usually the main sheet is eased a little, not always on some boats but usually and that takes the forward push load off the mast ... so mast can flap. Actually on a decent chord wing mast, the sheet has to be eased to allow the mast to rotate to new tack or gybe.
The boom to mast connection mount can be whatever you like, but conventional and simple spinnaker pole-like fitting, parrots beak and ring, does an excellent job; can move up, down and sideways, no pressure points.

 

Hi Gary,
Thanks for the reply about the mast construction. It was not boring at all. I have thoroughly enjoyed all aspects of this thread immensely as I have always loved the building aspect of things. How long of a mast could be built in this form do you think? How long were the masts that you have built for your boats?
Thanks again,
Tim