Subject: Re: [harryproa] Reducing sail with boom out over the water.
From: Doug Haines
Date: 3/7/2007, 2:49 AM

Hi ya,

I am getting a lot more food for thought, now that I work in a Schionning Cat Factory.
Something I sorted out in my mind today was the argument for general accomodation /cockpit layout in cats, tris and HP's.
I saw in Multihull World Sept 2003 just now, a GBE sportsdeck. Now I have never really thought of wanting o build or buy a bridgedeck cat  because of the huge living space, weight,windage and cost etc. I was heading more along the lines of trimarans (liking Chris White's designs) with accom. in a central hull. But this GBE sports deck reminds me of the HP Harryin that you get a little set of seats under cover with 360 deg. view and a helm station. The little table on the GBE would be good too, could be included at the expense of one of the double berths.  But that is all - no indoor sofas and kitchen. That's down below, same as with Harry. You're going to beat other cats in speed, and spend much less building.
Someone care to argue the bridge deck or a more Visionarry cruiser type saloon? Eg. Entertaining, warmth,
The cabin/saloon is open to LW when sailing, so this seems better than  a cat, where opening is aft, which could let weather in.

Also been wondering about matching up a longer LW like 15m with Harry WW 8.5 or 9m. Is that being too scared of the ocean and the 12m LW is plenty bouyant for surfing waves? Would you go up in rig too? Surely not up to Vis rig! Cross beams stronger or longer?



Doug Haines <> wrote:


For the booms: I liked the way the tow wraps around in the beams and thought a similar application applies here?
Remembering Uni Engineering - the corner points of a box section are higher loadedthan the middles of each side, due to forces from two diffrent directions. A boom would get forces sideways and up or maybe down too when sheeted in.

If the mast was done as a whole, then cut in half to fit the stub in, would you put two layers of db around as you would need two layers of db in a mast anyway and this way it holds the two halves together.

I'm guessing that the tapering section would mean you wouldn't really stagger the layers but have the constant number of layers all the way up?

Hope you can find aenough space for the kite on the river on a weekend, or will you try Cockburn Sound?
Hot today!

Rob Denney <> wrote:
Tube diameter sounds good, although the bigger it is, the stiffer the mast will be.  I can't see an easy way to get the stub in the mast without making it in 2 halves.  It also needs a bulkhead at the top bearing. 
I will let you know laminates in the next day or so.
If you are wrapping the tow round a tube on the mast and back onto the beam, then an I (This should be a capital i, but my keyboard doesn't have this.  The shape is the same as an rsj)  is better than a T.  Just be aware that i's are not very good at withstanding twist, so the main sheet should attach to the clew of the sail, rather than to the boom, unless the boom is heavily tapered.

Ya Hi,

Wel I'm trying to get the planning sorted for all the sizes and amounts of materials and things to start making the masts again:

I'll give you what I've got to so far. Changing the mast tubes ( termed mast step by Rob I think), that sit inside the hull in between the bulkhead halves. I made incorrectly small diameter tubes about 75mm inside diameter. So replacing these with I think it is 86mm inside diameter pipe. Wrapping carbon round that. No probs.  Re-doing the fillets from the bulkhead halves later and fitting tubes in. By the way staying with two masts.

Now with the tubes set I know I need the stub of the mast to be round 84mm or so.
This and the mast I want to do with solid carbon on molds.
I've got the foil section shape. I can scale this to get the molds all the way up tapering linearly to I'm guessing a good size is about half size at the top?
With the taper I'm confident that one piece molded will come straight off, though it may be to get the stub in if it is in two halves.
What I need is the lay up weights of carbon. Including the round stub.
Then also the boom. Do you mean I or T section boom?
It is attached with freee tube on the stub between wing and hull.
Wrap carbon tow around mast like design of beams?
I've got two 6m luff sails, so total mast is about 6+0.7+0.3+a bit  =7 and a bit metres.
PLease let me know what else I need to work on. I'm trying to bring the performancr (and looks) up to standard.

DOug wrote:
Rather than making a box boom you could consider an 'I' beam boom. This is much simpler as it doesn't require closing off, jus a top and bottom plate and a vertical web. The uni carbon or glass can be laid flat on the plates with double bias on the web to take shear loads. Hardware can be bolted through easily, lazy jacks can be tied at the bottom by drilling holes in the top plate. Wish I had thought of it before making the 4 Elementarry box booms :>(.
Let us know if you want to go that way and we'll send you details.
Mark Stephens
-----Original Message-----
From: [] On Behalf Of Doug Haines
Sent: Tuesday, 27 February 2007 9:16 PM
Subject: Re: [harryproa] Reducing sail with boom out over the water.

Thanks Rob,

I have had some fun trying to put a reef in while on the water - sailing the booms round inboard, dropping sails and pulling booms inboard, and sliding out along the hull to tie sails!

Doing it from at the mast is a necessity.




Rob Denney <> wrote:
Experimenting going ok.  Will be sailing tomorrow, all going well.
Glad the job is interesting, although it sounds like a bit too much effort for me!
The sail can be dropped with the boom anywhere, as long as the sheet is released so it aligns with the breeze.  The lazy jacks keep it in place, reefs don't need to be tied in.  Vis sail does not flake into the boom, is a bit of work to get it flaked and the cover on.  Not sure about harry as I have not sailed on it yet. 
The open boom is pretty complex to make, and the benefit on a little boat is negligible.  I would stick with the box and the lazy jacks. 
----- Original Message -----
Sent: Monday, February 26, 2007 8:11 AM
Subject: [harryproa] Reducing sail with boom out over the water.

Hello (Rob),

How's experimenting?
I'm busy with this new job - interesting, learnt how to get that mirror finish on the paint job (it's sanding again after painting 1200 grit floowied by polishing compound!)  and other proffessional tricks of the trade
I wanted to ask about reefing/dropping sails:
On the Harry/Visionarries,  can the mainsail  be dropped with the boom angled out over the water? Is this possible due to the lazy jacks and the hollow built into the boom?
When reefed does the sail flaked in the boom need ties to hold it in?
So therefore is this what I'd need to build for Elementarry?


brag_rotor <> wrote:
Hi Doug,

It bundles up in a civilised fashion the luff just concertinas - with
reef points you an make it all neat and tidy, but the only critical
attachment is at the clew, where we use a light line to haul it all
together for the mainsheet changeover. There's a second 'snap
shackle' on the mainsheet for that purpose. We make those out of rope
and save 32 a time.....

Photo of a reefed Wharram schooner here:-

Packing the sail into its cover can be fun if you are single handed,
but I can do it OK. Just wrap the sail around the gaff as
best you can, apply the gaskets or bunjees, and heave the cover on,
being careful not to make the sail too lumpy to fit.

This looks a very neat setup:- lbum=/Tiki-range/Tiki-30&image=DSC02289.JPG

But I suspect his sail material is half the weight of ours, and a lot
more malleable. Heavy duty HydraNet is a beast to furl, but we went
for its toughness and total lack of stretch. This means that we do
not worry about stretching the sails out of shape due to reefing, and
they didn't - even in a Biscay gale. Boilerplate sails.

Only bagging the sail single handed is any sort of tussle, anyway.
That's partly because the bag has to be tight to avoid flutter. Our
sail has lived in its bag since .... ummm .... 1999 I think. Just
hose it down and do some sewing on the odd seam once or twice a year.

Here's another neat one, without a sail cover:-

Gives you a chance to see how it's been furled. They are no hassle,
in our experience.

A bit off topic, one of Steve Turner's clients wanted a Tiki without
the 'old fashioned' rig, and had Steve build him one of his GRP boats
with a full-on 25% oversize battened bermudan rig, no expense spared,
so Steve and the gang then had a chance to sail it against a standard
production boat.

Interestingly the standard boat had the advantage everywhere, except
downwind - 25% more sail area made a difference there. So one might be
tempted to assume that the Wharram Tiki Wingsail had around 25% more
drive to windward/on a reach than the fully battened bermudan...?

Reason that I mention this is that I found a photo of what may be that
boat when I was looking for furled/reefed sails....
Might be a different boat, who knows. Not an improvement in our

All the best, Ben

--- In, Doug Haines <doha720@...> wrote:
> HI,
> How does the sail fold up at the sleeve when you reef or take the
sail down?
> Doug

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