What boatspeed should I expect, as a percentage of True wind?

[jmh2002]

Originally Posted by GRIT

Don't get me started talking about our specific boat, or it'll never end.

Oh, but it's nice to hear about your specific boat, that's also a very interesting part because it's very relevant to the whole performance discussion...

[smj]

Originally Posted by GRIT

Thanks for that SMJ.

No, we're not the 48.

We had Kurt make us our own design, from several of his plans. (the 45, the performance cruising 49, and the outsider 48)

We started with the 45 model (I read the Hull beam to length ratio was 10.9, but I think it was more like 11.2 ish) and had him stretch the hulls 4 feet, without widening them (which gives us about 12:1 hull beam to length ratio) We then had him shorten the bridgedeck by about 6 feet (using the mast beam from the outsider 48), lengthen the cockpit by 18 inches, we used the rudders from the performance 49, had him design a carbon bow beam, move the engines forward 6 feet, and several other mods to suite our preferences. We then nearly doubled the sail area of the stock 45 (which used to advertise as having 480 mainsail and 220 jib, we have 800 mainsail and 400 jib).

Kurt's retired our model, and has a new 45 with a bustle in the hulls, to widen them above the waterline. When asked about our boat, he calls it a "heavily modified" 45. He doesn't like the front cockpit, but likes the inside steering... We called it a 49x on our permitting papers. It actually measures 49.6 feet, not including the sprit.

We launched at just over 16000 lbs, without the mast but with more than 300l of fuel and a bunch of building supplies.

Don't get me started talking about our specific boat, or it'll never end.

Cheers.
Paul.

Hats of to both you and Chotu for doing something I could never commit to, a long term boatbuilding project! We had a contract on a Kurt Hughes years ago that fell through during the survey, the owner backed out of the deal. I’ve always liked his designs.
Do you use the website multihulldynamics.com? Great website that gives performance indicators based on manufacturers specs, so must be taken with a grain of salt.
Appears you are lighter than the 4X, have a slightly better lwl/bh but slightly less sail area, so maybe pretty comparable? Either way a boat to be proud of.

[GRIT]

Thanks SMJ.

That's no coincidence.

Knowing the original design was undercanvassed, we looked at comparable boats. We decided that the Outremer 45 ( which then measured 45 and now measures 48) was the closest we could find. The 4x didn't exist when we were designing the sail areas.

We used the 45 as the basis for our sail area. The ratios are a little different, since our mast is a good 4 feet further forward than the Outremer's is, so our mainsail is larger, and our jib is smaller.

We also used some ideas from the old style Gunboats, and the Chris White Atlantic series boats, for our front cockpit and helm layout.

I think we should be quite comparable, now that I know what their hull beam ratio is. I hadn't thought they were that skinny, so our design is much closer than I imagined. Yes, we should sail somewhere in between the 4x and the outremer 45, as our sail area is somewhere in between the two. All other dimensions and weights are also similar.

I have not used that site, but I'll take a look tonight.

Cheers.
Paul.

[GRIT]

Originally Posted by jmh2002

Oh, but it's nice to hear about your specific boat, that's also a very interesting part because it's very relevant to the whole performance discussion...

Thanks JMH2002.

If I start talking about what we've done, and why, I'll derail the thread completely!

I'm learning a lot from this thread. It's really nice hearing from folks like you, SMJ, 44C, FxyKty, et all. It's folks with experience on fast cats that have really made this thread an interesting read.

Cheers.
Paul.

[Sand crab]

Originally Posted by GRIT

Thanks JMH2002.

If I start talking about what we've done, and why, I'll derail the thread completely!

We want to hear more about your boat please. Actually yours and Chotu's too. Perhaps you can start a new thread and post pics (lots). Take us through the design and construction phase. We'll love it.

[GRIT]

That's very kind of you to say, Sand Crab. Thank you.

The boat's not yet finished. I'm going as fast as I can, but now that we're cruising; there's maintenance, and moving the boat here and there, that're slowing things down somewhat.

I hesitate to put interior photos up, but if there's truly and interest, I will start a thread when I get the Starboard hull finished inside.

For now, it will suffice to say, we're pleasantly surprised how well all our "modifications" have turned out.

Cheers.
Paul.

[fxykty]

Originally Posted by jmh2002

The 4X and 5X has quite a powerful (rotating) rig. Maybe you are still underpowered a bit, especially in cruising trim / payload?



If I remember correctly @fxykty was previously proposing a big headsail to be sheeted inside the shrouds to complement the self tacker on his earlier generation O55L.



I'm not sure if that eventuated, hopefully he will chime in here.

Still no upwind inside-the-shroud screecher for light wind upwind. With our 36sqm self tacker (plus 86sqm round top main) we are under powered under 9 knots TWS upwind. At best in flat water we can sail ~50% TWS but at closer angles 30-32* AWA due to the slower speeds for a reasonable but not exciting VMG.

I am still dreaming of a 70sqm screecher that will sheet to the aft corner of the cabin top for an effective angle of 6*. It only needs to go to 15 knots AWS so can be built fairly light. Unfortunately some structural upgrades take priority right now, but that sail and its sheeting position are next on the list.

All that said, due to our relatively new to us non-schedule cruising lifestyle we now wait if there’s not enough wind to sail well - fortunately on the mid Queensland coast that’s not too common. We do seem to be the one of the few boats willing to sail upwind though - we’re witnessing a lot of motoring or staying put during non-favourable wind directions.

Our gennaker (or code 0 I suppose it would be called now) does very well for AWAs 45-135* and even for wing and wing at 175* AWA. But except in really light wind (under 4 knots TWS, when we go slower) it’s hard to go upwind as the 90-100% TWS boat speed means our TWA is 75-80*.

I expect if we get the screecher then we’ll use the gennaker less and will want a large top down furling asymmetric for 80-170* AWA. We do have a symmetrical spinnaker that came with the boat but don’t use it much as it’s a bit more of a hassle to set up than the furling sail, but it does cover the 120-180* AWAs.

[JustMurph]

fxykty: I hadn't realised you were cruising the QLD coast, until I saw a photo of your boat pop up on my friend Dina's FB page (Fortuna). Small world!

[smj]

Originally Posted by Sand crab

We want to hear more about your boat please. Actually yours and Chotu's too. Perhaps you can start a new thread and post pics (lots). Take us through the design and construction phase. We'll love it.

I would really enjoy that. [emoji1303]

[jmh2002]

Originally Posted by smj

I would really enjoy that. [emoji1303]

Me too

[GRIT]

Thanks for your support guys. I'll see what I can do about that.

If I'm to start a thread though, it'll likely revolve around answering questions. That way I'm not just talking to hear myself talk. Perhaps other builders will chime in too.

I'll see about making some kind of video showing what we have, and why, which should get the ball rolling nicely.

Cheers.
Paul.

[GRIT]

Going back to the Original topic:

I'll be arriving in Ft Lauderdale, from St Augustine, in 2 hours or so. I was just looking at the average speed, and thought I'd post it here. Going slower overnight, with 2 reefs in the main, and a reefed jib. A fairly relaxing trip overall.

Winds 20 with gusts to 30 yesterday, and now winds 15 with gusts to 20. 160 awa yesterday, 120 awa now.

I meant to get a photo at 24 hours, but this is pretty close.

Cheers.
Paul.

[Chotu]

Originally Posted by GRIT

Going back to the Original topic:

I'll be arriving in Ft Lauderdale, from St Augustine, in 2 hours or so. I was just looking at the average speed, and thought I'd post it here. Going slower overnight, with 2 reefs in the main, and a reefed jib. A fairly relaxing trip overall.

Winds 20 with gusts to 30 yesterday, and now winds 15 with gusts to 20. 160 awa yesterday, 120 awa now.

I meant to get a photo at 24 hours, but this is pretty close.

Cheers.
Paul.

Very nice!

Giving me motivation to get my rig on this winter!

I think a relaxed overnight and max of 18 knots sounds like something I’d be quite happy with.

And you are getting these speeds SINGLE HANDED. I think that’s also important to note.

[GRIT]

You'll be happy with the rig on. It's a transformative moment, when you see it up. The whole world changes.

You're boat will probably be faster than GRIT, since you're so much lighter. I can't wait to see your numbers!

Cheers.
Paul.

[GRIT]

Originally Posted by GRIT

Going back to the Original topic:

I'll be arriving in Ft Lauderdale, from St Augustine, in 2 hours or so. I was just looking at the average speed, and thought I'd post it here. Going slower overnight, with 2 reefs in the main, and a reefed jib. A fairly relaxing trip overall.

Winds 20 with gusts to 30 yesterday, and now winds 15 with gusts to 20. 160 awa yesterday, 120 awa now.

I meant to get a photo at 24 hours, but this is pretty close.

Cheers.
Paul.

Those should both read TWA, not AWA. Apologies.