Multi-masted sailing cats

[jamez]

Malcolm Tennant designed a Schooner rigged 42'cat back in the seventies and re-drew it a few years later, incorporating knowledge obtained from sailing the prototype, with a single masted rig. I have attached a drawing of the original and a copy of the article on the Mk 2. The comments regarding sailing the schooner version make interesting reading. However the original may have been flawed by having the masts too close together. looking at pictures of Newicks 'Pats' and Chris Whites Juniper there seems to be a little more rig separation. The wharram schooner rig has the masts relatively further apart and seems to work well.

[robherc]

After reading that excerpt, and looking at the drawing, I'm reminded again of Eric's comment:

Originally Posted by Eric Sponberg

Because of the speeds involved, up to two masts is acceptable, but it would border on problematic to go with three, if only for the accumulating downwash effect of each mast on the other behind. The third mast would not generate that much usable lift.

Seems like having the 2 sails THAT close together, esp. with the mainsail being rectangular, you'd be creating all kinds of downdraft on the mizzen...almost enough to make me wonder if it wouldn't be able to move FASTER to windward with the mizzen mast removed...eliminate the drag from it.

I'd be interested to see how much (if any) difference moving the mainsail a couple feet forward would make in such a design.

[brian eiland]

The ketch-rigged Damfino, with its unstayed carbon masts, offers perky performance, hitting 16 or 17 knots off the wind in a stiff breeze.

Dick Newick's latest: http://tinyurl.com/Damfino

[brian eiland]

I've always been a fan of the ketch rig for a cruising vessel. I think you will find quite a few discussions and cross references in these individual postings in this subject thread:

Ketch Rigged Cat by Chris White
Aftmast rigs???

Diomedea Exulans
Aftmast rigs???

Brion Toss, on 'Mizzens'
Aftmast rigs???

[Fanie]

Hello Brian,

I was looking for you... didn't know you was hiding here Need to do some discussion on the aft mast with you if you have spare time.

As for multi masted muti-hulls I'm with Marshmat, personally I like the idea.

The cost increases exponentially on the larger stuff (liked that Philips mast... phew !) while smaller usually is cheaper, especially when you buy bulk like two of everything.

Smaller is also easier to handle, and you always have a backup if one half brakes down. It doesn't have to be complicated either. I just spent a few days in someone's boat yard, some things are awesome, some scary and some rigs makes you nausia like they just kept adding rigging (and weight )

I'm planning my second aft mast rig (Brian) if I can get the funds together. This time a cat with two aft masts. If I get my way it's going to be fast.

Btw, I did some testing the last 3 days on my little sloth I mean tri with the aft mast... discovered some neat things there.

[robherc]

Originally Posted by Fanie

I did some testing the last 3 days on my little sloth I mean tri with the aft mast... discovered some neat things there.

Please share...that sounds like the kind of info we could all benefit from! (unless you intend to use it as a trade secret... )

[brian eiland]

Originally Posted by Fanie

Hello Brian, I was looking for you... didn't know you was hiding here. Need to do some discussion on the aft mast with you if you have spare time.

I believe I saw something in the forums about this, but I've not spent much time here due to many other projects at the time including a long visit by my new wife from Thailand. Where was that reference?

[Fanie]

Hi Rob, maybe a bit later, I have to (yet again) make some changes to the sail to confirm what I think it's doing it actually does. Have to help the sail maker with his laser to (hopefully) get a bit of discount. It's amazing how the costs esculate when you try things out and have to chop and change all the time. Anyone want to sponsor this, must be peanuts for you guys.

Hi Brian, it's in the boxy fisher thread.

Sorry Marshmat, the intention is not to hijack your thread. As I've mentioned I favour two masts. If you have a cat for instance and you have two aft masts (my preference) it could lend itself very well for auto tacking etc. Haven't worked the details out but I am working on it. Better performance, more sailing area and the shorter masts won't even be seen by pyrates

[Fanie]

Oh I forgot to mention Marshmat, it may well be possible to sail directly to wind, if I get the rig I want together I may well be able to do so. I hope this would spark some fire, I'm tired of hearing how many thousands and thousands of years nothing in sailing has changed and that it's at it's best and optimised already Every second 'sailing' guy tells me that.

I even had one guy tell me the philamons on Lake Cariba have been using this aft mast setup for centuries and is only good for sailing downwind. I've just been sailing in and out of his marina for three days and he hasn't noticed us coming in or going out no matter which way the wind blew good grief. You can probably tell he's a hardcore monohuller and he probably missed that I'm not a philamon from Lake Cariba too

[marshmat]

I would be very curious to hear more details of how your test boat is working out, Fanie. I can think of a few ways one could mount a double aftmast setup; if it's not a "classified" project, would you be able to put a photo or two up so we can get a better idea of how you've set it up?

The ability to self-tack does seem to hold a fair bit of appeal to many people. Tall, high-efficiency windward rigs with big overlapping genoas may be powerful, but whenever the yacht club holds a race, the guys with this kind of rig have half their crew out on the foredeck wrestling with the sails. For cruising, I think there is something to be said for a rig that handles itself as much as possible, and can be controlled from the helm station without electrics.

On another note, to spark further discussion, let's say for the moment that we accept that two or three masts on a cat/tri will be less efficient than one mast. Let's also hypothesize that a sloop-rigged cruising cat will typically outrun a cruising mono sloop (of comparable cost and living space) by 50% or so, averaged over a few days of sailing on all points. I would think that after switching each boat to a 2-mast ketch or schooner, or 3-mast schooner, the cat will still be substantially faster than the mono (although it probably won't catch its sloop sister to windward). And it'll do this without heeling, and- if spreaderless shrouds, luff pockets or rotating masts, and relatively short booms are used- will be able to set its booms forward of the beam when running. Or would we expect something different?

[robherc]

Hmmm....this is still in the "I've though about it for 15 seconds and it MIGHT have a chance at working stage, but here you go (don't just shoot from the hip please, give it some thought before you go throwing rotten vegetables at me for this):

What if, instead of a rotating mast (EXPENSIVE), or a luff-pocket (hard to reef), we made one or more booms long enough to connect to EITHER mast? So, when running, we could sheet in the boom, connect it to the rearward mast (if the masts are the same height, that's the only way this would work), and then have another sheet that controls which mast the head of the sail is attached to...let out slowly on the foremast headsheet as you take in slowly on the aftmast headsheet (kinda like what you do when tacking a genoa). Finally, pull the pin on the front connection for the boom (to the foremast), then sheet it out to where you want it & POOF...270-360* tackability!

Anyone think this has ANY chance of being viable...even if only to freak out everyone else on the water?
(I'm working on a rough sketch, I know it's a bit hard to envision)

[robherc]

OK, here's the sketch.
So far I'm still thinking it's a POSSIBILITY...though it'd prob. take at least 3-4 more sheets to control the attachment of the mainsail to the diff. masts...and a way to attach/detach the sheets...but I haven't worked that part out yet.

So, I guess the real question is: Does anyone think I'm NOT completely friggin' looney for this idea?

[ancient kayaker]

Matt:

getting back to your original question, I think the real answer may be very simple. In a mono if you need more power and your mast height has reached the limit of what the hull will hold up in a breeze then adding another mast makes sense. A cat will cheerfully hold up such a tall rig than a mono that the need for another mast is not there.

[Fanie]

The rig I'm working on is not classified, but in an attempt not to throw rotten vegetables at this, I would like to test a few things first. I don't have anyone around here willing to stick his neck out (time & money) to help me with anything so proceedings are painfully slow and it is difficult to do everything single handedly, especially the cleaning up afterwards

At this stage I have only a little tri that is poorly shaped for any kind of speed, I'm not a tri fan either, I favour cats (even the hairy ones and especially the two legged ones ) The little tri is also not suitable for more than one mast, so I must look at getting or building two hulls first.

The only drawback two sails may have is on a beam reach or broad reach, depending where the aparent wind direction is. In this case you have one sail doing all the work while the other world contibute less to foreward motion, but would it be so bad ?

The rig must be a single handed one, or two if you have someone with you. Isn't that the ideal, instead of a bunch of guy's wrestling with stuff. I think it is well possible, if I'm not mistaken some rigs are like that.

[ancient kayaker]

I have seen several cats with two masts, one on each hull. Have you considered this arrangement? At first sight it would seem that one sail would blank the other on a broad reach but the speed of the boat moves the apparent wind toward the bow. In a fast boat blanking is probably only a problem with the wind well aft in which situation one can either tack downwind or rig the booms out.