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  #1  
Old 07-09-2011, 10:06 PM
rapscallion rapscallion is offline
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Low Budget Racer

Here is the 3d iteration of the low budget 23' racer. First a recap of the design brief:

1.) true trailer sailor... No slip needed... so it needs to be able to be set up and launched very quickly.

2.) recycled beach cat rig.. Hobie 16 should be doable, Hobie 21 would be the best...

3.) as fast as possible in light of the budget and builder skill limitations...

4.) solo Chi-Mac capable (need some cabin space for gear and protection from the elements, and obviously seaworthy... Lake Michigan can be a harsh mistress...


I thought the Newick Val was a great boat to look at because of it's offshore success. I decided to use a center cockpit like the Val 31. Extren beams are used for the Beams Like the L7 Design. Dory hulls because they are easy to build, and If I use the ultraply like what was used in slider the boat can be built on a low budget.

when the boat is loaded down to 2200 lbs, it will draw 12"... hopefully it wont be that heavy when racing... The Amas when submerged half way, they have close to 2200 lbs of buoyancy. I don't want to fly the main hull, I was going to put Daggerboards in the amas to gain room in the already cramped cabin..

The boat should weigh less than 1200 lbs with the rigging and outboard included, and should set up rather quickly..
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Old 07-09-2011, 10:08 PM
rapscallion rapscallion is offline
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here it is
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  #3  
Old 07-09-2011, 10:33 PM
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Doug Lord Doug Lord is offline
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Quote:
Originally Posted by rapscallion View Post
here it is
===============
Raps, whats the L/B main and ama? Consider angling the amas a bit otherwise they'll get wider as they become immersed. Looks good.
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Old 07-10-2011, 01:13 AM
ThomD ThomD is offline
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I think if you are considering what you are considering, a good place to start would be the Newick Tremolino. Study the evolution of the plan over the decades. It is a Val 31 cut down to 23 feet, except that it got that whole use Hobie parts millstone for a while.

Another good boat to study is the Hughes, 23 Tremolino Eater. A boat improved from the Tremolino in pretty much every respect, as far as speed is concerned. Mine uses the Hobie 18 rig, and I find it sails well. The latest version is a quantum leap in every respect over mine.

The boat you have drawn would not have made a good shot at the economy racer thing much beyond the 60s. Look at 1:49 in this vid, the blue boat:

http://www.youtube.com/watch?v=qYmKqu4zIs8

A hull for their 24 footer is in their book. Cheaper, and lighter to build that what you are proposing, and already over 40 years "obsolete". Only problem with this kind of boat is you need a dry place to build. Nice thing about dory style boats is you can stage them from a single car garage, yet assemble them in the open. Sad to give up so much efficiency though. If I had serious restrictions, I might try building in the garage, and doing strip plank below the waterline, the rest dory, and the strip could be coated in the shop and taken out already sealed. You can even do it in several pieces. Don't worry about lofting there are ways of doing that with a few patterns and no real big brain work. The idea would be sorta L7 but you make all the parts. Home builders and pros did it before L7 did, think Gold Coast.

I have some experience with these tube boats, and they are a nightmare to set up. Probably someone has one that will set up in 10 minutes, but in general they are an all day thing, best case. The L7 seems like a whole lot better for launching, but has some limitations form wise. If you can get them it would be a lot better off the ramp than what I have.

I would try to keep the displacement in the 1700 pound range, max. That should be your design waterline, not to say you can't pile more people on. And therefore you weight budget needs to be just fat of 1100 pounds. The numbers for my boat were actually 800 and 1200.
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Old 07-10-2011, 06:57 AM
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gonzo gonzo is offline
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The minimum length for the Mac is 24 feet. Also, read the safety requirements. What you are proposing won't be allowed to race.
http://www.cycracetomackinac.com/the...ace-documents/
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Old 07-10-2011, 09:02 AM
rapscallion rapscallion is offline
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The main hull is 24' exactly. The beam is 17' 4".
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Old 07-10-2011, 10:15 AM
rapscallion rapscallion is offline
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Wow. The Gougeon 32 is in many respects exactly what I was looking for. I love the easy launch and dropping the mast to go under a bridge features... I know they are working on a wood/carbon fiber pod catamaran racer with many of the Gougeon 32 features.

And as for performance, I would like the boat to perform as well as the L7 and F25c. The L7 is rated very closely to the F25c, and that performance point is what I'm shooting for..
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Old 07-10-2011, 01:20 PM
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You won't even be close with the rigs you mention. Also, with old sails and gears you won't be competitive. Racing is expensive. You got to get good gear and be able to afford breaking it.
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Old 07-10-2011, 01:34 PM
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I agree with these recent comments.

I have seen a F25c overtake a ULDB 70fter to windward (Makika versus Icon) in the Van Isle 360. So it is much higher performance on all points of sail than you can ever get with a recycled beach cat rig. Even if you use a Tornado rig you'll need bigger headsails and then you have possible mast flex problems.

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Old 07-10-2011, 04:15 PM
rapscallion rapscallion is offline
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I have never seen an F25c sail, and I believe Richard's assessment of it's performance. The L7's Phrf rating is close to an F25c, But it doesn't use a beachcat rig either. The prototype did however, and it held it's own on the race course.

I have a 28' keelboat that i race on occasion... I have an idea how expensive racing is.. new sails, lines, crane fees, slip fees, bottom paint, ect...ect... I think the gougeon brothers were on the right track with the G32.

Most of the multihulls that race on lake michigan are F27s and F24s, with the occasional F31 and F28r.. The only multihull I have raced against was a contour 30, in a 138 mile solo race last year... the race took 36 hours... and the contour 30 only finished a couple of hours ahead of the keel boats... I would think a plywood trimaran would be able to be competitive in this area...
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Old 07-10-2011, 04:34 PM
bruceb bruceb is offline
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Racing isn't cheap

Rap, I didn't pay hardly anything for my used Buc 24, but by now with it starting to get competitive (it is, I am not), the necessary equipment adds up quickly. Say multihull and keep it light, and the cost goes up again- and you really can't do without some of the "racing" parts. Just be aware, the hull/hulls have very little to do with the total. If you design it to use some popular existing classes sails, it helps, but still a compromise both for performance and design. B
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Old 07-10-2011, 05:55 PM
cavalier mk2 cavalier mk2 is offline
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Stick to your point # 3 and have fun, you'll be able to compete with the other boats in your skill/equipment range and figure out if your skill improves. Expensive gear doesn't help if you don't know what to do with it.
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Old 07-10-2011, 06:16 PM
Corley Corley is offline
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Your boat hullshapes remind me strongly of Joe Dobblers Triad with it's angled planing floats. I'm not sure how that boat went but I'd speculate slow in light winds as the form drag would be quite high till you get on the plane I was reading about it the other day in the AYRS edition #55 from 1965.
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Old 07-11-2011, 02:00 AM
jamez jamez is offline
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Quote:
Originally Posted by rapscallion View Post
I have never seen an F25c sail, and I believe Richard's assessment of it's performance. The L7's Phrf rating is close to an F25c, But it doesn't use a beachcat rig either. The prototype did however, and it held it's own on the race course.

I would think a plywood trimaran would be able to be competitive in this area...
Don't forget the nut behind the wheel (and that's a figure of speech not an insult. IIRC designer Mike Leneman was sailing the L7 when it made some of those giant killing performances. It certainly shows the boats potential, but I don't think a less experienced racer could count on repeating it out of the box....

A ply boat (and the L7 is mostly) could do similar but it would need to be light, have a good rig and a skipper not afraid to put the foot down.
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Old 07-11-2011, 05:47 AM
rapscallion rapscallion is offline
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Originally Posted by jamez View Post
Don't forget the nut behind the wheel (and that's a figure of speech not an insult. IIRC designer Mike Leneman was sailing the L7 when it made some of those giant killing performances. It certainly shows the boats potential, but I don't think a less experienced racer could count on repeating it out of the box....

A ply boat (and the L7 is mostly) could do similar but it would need to be light, have a good rig and a skipper not afraid to put the foot down.
Agreed. I have never met Mike, but I have no doubt he is an exceptional sailor. All the comments about racing being expensive are correct, what I'm trying to do here is build an inexpensive boat that will allow me to race PHRF against other multis on mostly lake Michigan. Racing PHRF is kinda like league bowling...

I was excited to see the potential of a ply boat in this size with the performance of the L7, and I was hoping to get as close to that as I could given budget constraints. But maybe dory hulls are not the answer considering the average windspeed on lake michigan is 8mph during the june july and august. at higher windspeeds I didn't think the dory hulls would hurt performance that much, but in lighter air it may...
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