505 plans?

[dirkklein]

hi all! i'm new here

i am looking to self build a sailing dinghy and was hoping that someone here could help. i have already done some research with regards to what type of dinghy i'd like to build, the i 505.

my reason is that it is still a very active class.

does anyone know where i can find a set of plans for this boat? and after that where i can get the sails and spars? i will be happy to purchase them.

i have found many manufacturers but none offer the sell plans for a self build project.

any help or a point in the right direction will be much appreciated!

dirk

[gggGuest]

Try the class association...

But the 505 would be a very challenging project as a first build,and very expensive and time consuming, because you need to build a mould, not just a building jig for the hull. Lovely boat but I wouldn't want to tackle one as a home build until I'd done a couple of simpler boats first. In fact, even having done some simpler boats, I'm still not sure I'd want to tackle one!

[Doug Lord]

In case you haven't seen this: http://www.int505.org/old_site/build01.htm

contact list-you can probably track down plans from here-but I'd listen to gg if I were you:

http://www.int505.org/index.php?option=com_contact&view=category&catid=18&Itemid=71

[CutOnce]

Try the class association...

But the 505 would be a very challenging project as a first build,and very expensive and time consuming, because you need to build a mould, not just a building jig for the hull. Lovely boat but I wouldn't want to tackle one as a home build until I'd done a couple of simpler boats first. In fact, even having done some simpler boats, I'm still not sure I'd want to tackle one!

The traditional way to get into the 5o5 game is to take a female mold off a known "good" hull, and then tweak it to incorporate the interpretation of measurements that will result in the best speed potential according to the "new" hull designer. This is a time honored tradition, and it requires you know someone willing to let you cover their hull in release compound while you make a 'glass mold. Once you got your female mold, you could pull a male plug out of it and use that for cold molding a wood veneer hull. Usually, the female mold is used to form 'glass hulls. People heading down the 5o5 production road usually tweak/fair/reshape a male plug pulled from a female copy till they've reached their shape goals. Once they've got an acceptable "master" they build female molds from it.

The most desired 505 hulls are Waterrats (Larry Tuttle) and (Mark) Lindseys as well as Hamlins (an isotope of the former) - usually with foam/hexcell core and kevlar layup. More generic are the Parkers etc. If I were investing in getting into the 5o5 game, I'd seek out a well-reputed owner of a top boat (one of the above builders) and start copying from there.

This all depends on how tough you are on intellectual property concepts. Personally, I could not do it, but many others have not got a moral problem with copying.

The latest 5o5 mold pulled I know of is at Phil's Foils and was pulled off a Parker hull. You could contact the former builder of Witchcraft 5o5s on Sailing Anarchy as he has a mold as well (as I last knew). I'm not sure if anyone else in North America has a mold around.

As others have mentioned 5o5s are a very challenging build target, and you may be better to consider something like a SwiftSolo or Quetzal build as these are more attainable.

--
CutOnce

[gggGuest]

Once you got your female mold, you could pull a male plug out of it and use that for cold molding a wood veneer hull.

More complicated than that, because the plug would be too big for cold moulding a wooden shell onto - the mould needs to match the *interior* dimensions of the finished shell, and a plug from a mould flopped off an existing boat would match the *exterior* dimensions. I suspect you'd be better off building a mould from scratch - probably strip planking it, which is of course at least as big a job as building the hull is.

I believe that SA has a Fireball fleet, and that would be about ten times as good a boat for home building.

[CutOnce]

More complicated than that, because the plug would be too big for cold moulding a wooden shell onto - the mould needs to match the *interior* dimensions of the finished shell, and a plug from a mould flopped off an existing boat would match the *exterior* dimensions. I suspect you'd be better off building a mould from scratch - probably strip planking it, which is of course at least as big a job as building the hull is.

I believe that SA has a Fireball fleet, and that would be about ten times as good a boat for home building.

Correct. I was writing fast and fingers exceeded brain speed. Fireballs are great boats as well, but the new "widebody" 'Balls made out of Kevlar have conclusively surpassed the performance of woodies. There was just a thread last month on building Fireballs on Sailing Anarchy, and it pretty much concluded the days of competitive woodie Fireballs are over. Like most classes the desires of the 10% at the front of the fleet ends up killing 90% of the participants ability to compete. It is really hard to balance "progress" with the incredibly easy result of obsoleting the fleet and killing the class. As soon as the class association let exotic layups get in, the decline in numbers started. This is the very issue the 5o5 people are fanatical about preventing - hence no carbon spars yet.

A really good helm in a woodie Fireball may be competitive at the club level, but to be in front at the Nationals/Worlds level is not possible any more in a homebuild.

--
CutOnce

[wet feet]

Doug gives a very useful link:read it thoroughly and it should help with a decision.A builder that seems to have escaped a mention is Rondar-they produce a good boat and Mader are worth studying.A 505 is definitely a challenge for a builder but a splendid boat even if my opinion is that the larger spinnaker spoiled the boat for close reaching.

[Doug Lord]

Doug gives a very useful link:read it thoroughly and it should help with a decision.A builder that seems to have escaped a mention is Rondar-they produce a good boat and Mader are worth studying.A 505 is definitely a challenge for a builder but a splendid boat even if my opinion is that the larger spinnaker spoiled the boat for close reaching.
===
WF, didn't the 505 class just decide to go with an asy spin?

[gggGuest]

but to be in front at the Nationals/Worlds level is not possible any more in a homebuild.

But as there are probably only about a dozen people in the world for whom that matters isn't it rather pointless for everyone else to be worrying about it? People vastly overrate the importance of boat speed. The average race is about 25% time variation between first and last. Even at the Olympics its usually between 10% and 15%. I have a limited amount of data which suggests that the difference between a tired old boat *with tired old sails* and a new one is about 5%. The difference between the latest whizzy wide bow kevlar fireball and an otherwise identical wood one is going to be far less. Yes, those few seconds really count for the top ten at the worlds when it comes to getting the nose out in front on the start line and being the first to clear air, but for the rest of us? Reckon it will be more or less impossible to tell the difference.

Especially when the most likely alternative is one of the ghastly "web site full of plans" boats you see about the place. A new wooden fireball with new rags etc is still going to be at least as quick as 90% of the Fireballs in the world and, with all the support available in terms of boat layout, tuning and all, not to mention other Fireballs to race against, is going to be a far better sailing experience than any of those specials.

[CutOnce]

===
WF, didn't the 505 class just decide to go with an asy spin?

No. The new long luff spinnaker on the 5o5 is symmetrical. There is a 5o5 variant in the UK that has an asymmetrical but it sure doesn't measure in as a 5o5.

With the long luff spinnaker, the 5o5 has improved it's options going downwind - it doesn't reach as high as it could with a flatter small kite, but it can soak and go dead downwind a lot better. It is a faster boat around the cans with the big rag.

The bigger kite made things a little more complicated with double poles, and trap twings becoming almost essential. We've got one of the largest fleets of 5o5s in North America here and the original small kites are not in use at all.

--
CutOnce

[CutOnce]

But as there are probably only about a dozen people in the world for whom that matters isn't it rather pointless for everyone else to be worrying about it? People vastly overrate the importance of boat speed. The average race is about 25% time variation between first and last. Even at the Olympics its usually between 10% and 15%. I have a limited amount of data which suggests that the difference between a tired old boat *with tired old sails* and a new one is about 5%. The difference between the latest whizzy wide bow kevlar fireball and an otherwise identical wood one is going to be far less. Yes, those few seconds really count for the top ten at the worlds when it comes to getting the nose out in front on the start line and being the first to clear air, but for the rest of us? Reckon it will be more or less impossible to tell the difference.

Especially when the most likely alternative is one of the ghastly "web site full of plans" boats you see about the place. A new wooden fireball with new rags etc is still going to be at least as quick as 90% of the Fireballs in the world and, with all the support available in terms of boat layout, tuning and all, not to mention other Fireballs to race against, is going to be a far better sailing experience than any of those specials.

I agree on the reality of the issue, but people's perception is quite another thing. Anyone not in the front of the fleet is scrambling for answers/excuses, and the wide bow excuse is widely accepted as why people aren't fast enough. One blown tack can wipe out the advantage, but that isn't usually admitted to in the bar.

Our fleet of Fireballs is shrinking, while the Albacores, 5o5s and I-14s are growing. Just an observation.

I'm in complete agreement about building a Fireball and think even considering a 5o5 build is way too much of a project with very little chance of success. Better off to buy a thrashed 5o5 for $3,000 sail it for two years and save your money to afford a Waterrat at about $25,000 used if you want any chance to be competitive.

A $5K build of a new Fireball would put in the game at club and regional level racing.

--
CutOnce

[Doug Lord]

No. --
CutOnce
===============
I guess they're just talking about it:

from Scuttlebutt, March 17, 2011:

WILL THE 5O5 BE THE NEXT SPRIT CONVERT?
The 5O5, so named for its length of 5.05 meters, achieved international
status in 1955. The class is now preparing for its 2011 World Championship
next week in Hamilton Island, Australia, but it won't just be competition
for the nearly 90 entrants. As 2009 World Champion Mike Martin details
below, the class will be giving thought to a major change for its future:
----------------------------------------------------------------------
The class is looking for ways to make the boat less expensive, simpler,
more versatile for crew. We looked at all sorts of things and determined
that converting the boat to a sprit pole and an asymmetric spinnaker would
accomplish these goals. The retrofit alone from the symmetric spinnaker and
current pole system to a sprit takes 40 fittings off the boat.

With the 5O5 being a two man symmetric spinnaker boat with the crew on
trapeze, the crew has their hands full with this very critical job of
gybing. I think with this change, the boat becomes easier to sail, makes
the boat less expensive, and easier to rig. And now that we have tested it
with the sprit that Larry Tuttle built and the asymmetric spinnaker from
Ethan Bixby, we have found that the boat sails great in this format.

Some may contend that we will lose tactical 'sit down sailing', but we
actually only sail deep downwind angles in a 3 knot zone (around 8 knots).
If it's light air, you're sailing tight angles. If it is windy enough to be
trapezing, you're sailing tight angles. And I contend that the tighter
angle sailing typical of asymmetrics is more tactical. You still need to
call shifts but you also are choosing sides, whereas deep running you might
be aiming close to the downwind mark the whole time.

Additionally, the class has long been committed to using reaching legs in
their championship course. The Worlds course is now windward, leeward,
windward, triangle, windward, leeward. The reaching legs are a lot of fun,
and while some people consider them less tactical, I have passed a lot of
people over the years on the reaches.

The primary system in the class for years had been a single pole on a
trolley. But when the class approved carbon spinnaker poles a couple years
ago, the weight savings allowed for a double trolley pole to be used. I was
opposed to the move to carbon because we had a boat handling advantage with
the single pole, but now the double pole has made gyping easier so that
more teams are proficient. So the development of the system has helped
equalize the fleet, but it also added a lot of complexity and cost to the
boat. -- Full report and photos, with comments from Andy Burdick of Melges
Performance Sailboats and Ethan Bixby of North Sails:
http://www.sailingscuttlebutt.com/news/11/0316/

[CutOnce]

===============
I guess they're just talking about it:

from Scuttlebutt, March 17, 2011:

WILL THE 5O5 BE THE NEXT SPRIT CONVERT?
The 5O5, so named for its length of 5.05 meters, achieved international
status in 1955. The class is now preparing for its 2011 World Championship
next week in Hamilton Island, Australia, but it won't just be competition
for the nearly 90 entrants. As 2009 World Champion Mike Martin details
below, the class will be giving thought to a major change for its future:
----------------------------------------------------------------------
The class is looking for ways to make the boat less expensive, simpler,
more versatile for crew. We looked at all sorts of things and determined
that converting the boat to a sprit pole and an asymmetric spinnaker would
accomplish these goals. The retrofit alone from the symmetric spinnaker and
current pole system to a sprit takes 40 fittings off the boat.

With the 5O5 being a two man symmetric spinnaker boat with the crew on
trapeze, the crew has their hands full with this very critical job of
gybing. I think with this change, the boat becomes easier to sail, makes
the boat less expensive, and easier to rig. And now that we have tested it
with the sprit that Larry Tuttle built and the asymmetric spinnaker from
Ethan Bixby, we have found that the boat sails great in this format.

Some may contend that we will lose tactical 'sit down sailing', but we
actually only sail deep downwind angles in a 3 knot zone (around 8 knots).
If it's light air, you're sailing tight angles. If it is windy enough to be
trapezing, you're sailing tight angles. And I contend that the tighter
angle sailing typical of asymmetrics is more tactical. You still need to
call shifts but you also are choosing sides, whereas deep running you might
be aiming close to the downwind mark the whole time.

Additionally, the class has long been committed to using reaching legs in
their championship course. The Worlds course is now windward, leeward,
windward, triangle, windward, leeward. The reaching legs are a lot of fun,
and while some people consider them less tactical, I have passed a lot of
people over the years on the reaches.

The primary system in the class for years had been a single pole on a
trolley. But when the class approved carbon spinnaker poles a couple years
ago, the weight savings allowed for a double trolley pole to be used. I was
opposed to the move to carbon because we had a boat handling advantage with
the single pole, but now the double pole has made gyping easier so that
more teams are proficient. So the development of the system has helped
equalize the fleet, but it also added a lot of complexity and cost to the
boat. -- Full report and photos, with comments from Andy Burdick of Melges
Performance Sailboats and Ethan Bixby of North Sails:
http://www.sailingscuttlebutt.com/news/11/0316/

I know Ethan - he's made sails for me. The asym experiment on the 5o5 by Tuttle/Bixby and also the "Alto" effort in the UK are interesting, but given the glacial speed of change in the 5o5 class things aren't going to happen any time soon. Everybody just spent a lot upgrading masts & traps for the long luff spinnakers, and they are all spending on dual poles systems and fittings. Add that to carbon booms and poles and the cost of the arms race in the 5o5 class is already high and the amount already invested is significant.

There is no way the existing fleet is going to vote to obsolete things yet again - the carbon mast issue has been on the table for 15 years without resolution. You don't have to just sell new fleet members on major rules changes - you have to sell a majority of the existing fleet before it even becomes an issue. I'm sure Larry and Ethan would "professionally" like the fleet going to asyms - Larry makes a bundle on retrofit kits right now - his spinnaker tube refit kit is the best option to convert bag boats to launchers. I helped with a conversion installing a "Larry" offset launcher a while ago. Ethan would love his North Gulf Coast loft to make new asym spins to sell to the same people who just bought long luff kites. Basically, the people who are talking up the change are those who stand to make the most money from it.

Don't take my word for it - go to any 5o5 regatta and listen to the people in the bar. You can't get 5o5 fleets to reach consensus on the wetness of water and the color of the sky. This idea (great as it is - I'm an asym guy myself) isn't going to fly within a ten year window.

--
CutOnce

[Doug Lord]

Here's a great picture of the 505 from the World Championships going on now in OZ( http://www.505sapworldchampionship2011.com/2011/03/26/ ) :

(click on the image)

[gggGuest]

... and also the "Alto" effort in the UK are interesting...
from what I can make out the Alto thing has shifted about 5 boats, which if correct suggests there isn't a huge untapped market for a sprit kite rigged 505...

[CutOnce]

from what I can make out the Alto thing has shifted about 5 boats, which if correct suggests there isn't a huge untapped market for a sprit kite rigged 505...

Same opinion here. 5o5s are sophisticated and complicated machines that require finesse and skill above and beyond boats like an RS800 or Laser 4000 to sail. The long luff symmetrical spinnaker adds to the challenge and workload during maneuvers, making the crew slot perhaps even more demanding than helming.

I can't see the 5o5 crew union lowering the bar any time soon.

Besides, if you want an asymmetrical two man boat there is no lack of options already.

--
CutOnce

[woudaboy]

I think there might be some confusion here. When the original poster refers to an i 5o5, is it possible he is referring to the i550 that is commonly made as a home built boat?
such as:
http://tokyotrashbaby.blogspot.com/

[Doug Lord]

From Scuttlebutt tonight:

REVISITING A SPRIT FOR THE 505


The International 505 fleet held its Annual General Meeting during the SAP
505 Worlds 2011 last month on Hamilton Island, Australia. Mike Martin, 2009
World Champion and recently appointed Chief Umpire of the America's Cup 34,
made some comments prior to the regatta on the possibility of the fleet
converting to a sprit pole as reported athttp://www.sailingscuttlebutt.com/news/11/0316/).

Following the AGM, Martin provided some feedback on what went down:

"Just to get a feeling of the class's interests we took a show of hands to
see who was in favor of going to a sprit - it wasn't an official vote - just
to see who was generally in support of it and who generally wasn't. I'd say
it was 60% in favor and 40% were against but then again, that was people at
the Worlds who are generally more progressive than the people who don't go
to the Worlds. In order for it to pass it's a vote by the majority of the
entire membership so it's still pretty on the fence.

My general pitch is that it's going to make the boat easier to sail - the
hardest part about sailing 505s is that it's really hard to find a crew.
It's a very difficult job up front and it's very busy so it'll make finding
crew easier, it's probably going to make the boat more tactical because it's
easier to jibe and it's going to make the boat cheaper because right now we
have this twin spinnaker pole system with two topping lifts and two guys,
two sheets, pole back systems and retractors - it's going to take about 40
fittings off the boat to go to a asymmetric kite so that's my pitch." --Read on: http://tinyurl.com/3knddek

[wooden505]

Hello Dirk,

here are some pictures of my wooden 505 project in progress. >>> http://www.okaycompany.de

Section drawings ("plans") and offsets are available on the international and the german 505 web sites.
I am quite involved with the international 505 class association in technical terms. Maybe I can help in case of questions.

Enjoy both - building and sailing ...

Andreas

[Paul B]

Hello Dirk,

here are some pictures of my wooden 505 project in progress. >>> http://www.okaycompany.de

Section drawings ("plans") and offsets are available on the international and the german 505 web sites.
I am quite involved with the international 505 class association in technical terms. Maybe I can help in case of questions.

Enjoy both - building and sailing ...

Andreas

That is a beautiful looking construction.

Is the shape per the original plan, or is it "massaged" per some of the modern shapes (Waterat, etc)?

Can if be built to the minimum weight?

[CT 249]

Hello Dirk,

here are some pictures of my wooden 505 project in progress. >>> http://www.okaycompany.de

Section drawings ("plans") and offsets are available on the international and the german 505 web sites.
I am quite involved with the international 505 class association in technical terms. Maybe I can help in case of questions.

Enjoy both - building and sailing ...

Andreas

Beautiful boat - and what looks like a Cobra Gun 320 windsuirfer from 1984!

A mate of mine still has one of those - the windsurfer, not the 505.