Perry Sliver Class Day Sailor

Nessun Dorma

Super Anarchist
A friend of my father's had a split rig semi-custom boat where the mizzen was not in line with the mainmast. Said she sailed just fine (I was too younf to remember how she sailed), but the offset was noticeable. Even if it did sail with the mizzen off to one side (I guess you compensate), it would drive me bonkers just having to look at it every day. Come to think of it, I think the mizzen mast was behind the cockpit so they never saw it. Still, it suggests shoddy craftsmanship at best.

I once had a consultation client who owned a well known semi production boat. He had becvome obsessed with the fact that his entire deck was off to one side as much as 4". He had 4" more side deck on one side than he had on the other. He liked the boat but he was worried about the asymetry. The builder reassurred him by telling him, "That's what you get when a boat is hand built." I didn't agree. I like precision. It would drive me crazy to think my mast was not centered over the keel.
 
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Bob Perry

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When we did the Freeport 41 we needed volume in the cockpit coaming for headroom in the passageway aft. So we just shifted the entire cockpit off to one side to make one coaming bigger, i.e. wider. I don't recall anyone noticing it.

 

kimbottles

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Very cool Kimb! Was the boat bolted to the rollers?
The wheels were a tight fit, but we still had a few attachment points to make sure it all stayed together.

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SemiSalt

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WLIS
I once asked Jim how we knew the deck would fit the hull and his reply: "Kim, it is all the same computer file, of course it will fit."
As a computer programmer, it drives me crazy how much people trust what comes out of a computer. (Even more than how they trust the computer, printer, internet connection, or copier to work every time and especially when they have a deadline.)

 

Dan33

Super Anarchist
When we did the Freeport 41 we needed volume in the cockpit coaming for headroom in the passageway aft. So we just shifted the entire cockpit off to one side to make one coaming bigger, i.e. wider. I don't recall anyone noticing it.
I found out when I put the new traveller track on GK that the cockpit was off centre 1/2"...I did all the measurements from the centre line of the boat and couldn't figure out what it was always favoring one side.

Until then, I had no idea. God bless curved surfaces.

 

beauvrolyk

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All Moore-24 boats (only 24' long) have the cockpit about 2" off center. The toe rail on one side is about 1.5" longer than the other also. No one has ever been able to measure a performance difference between the two tacks. Other than that, the boat is wonderfully well built.

This is because Ron Moore used a car jack to push the mold out wider when he "designed" the Moore from a boat that George Olson had "designed". Now George was a real designer and did some great work. Ron a good builder was just trying to get his little 24' boat built using one of George's older cast off molds and got it almost right. He built one hell of a great boat from that modified mold.

The genoa tracks look a little odd as they line up with the toe rail right but not with the cockpit.

The boat sails great - symmetry is over rated - none of us are symmetrical!

BV

 

Tucky

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Maine
My family owned a Rhodes 18, built in 1965 by Cape Cod Shipbuilding (small early fiberglass builder). Typical white gelcoat. I got all excited about painting it black back in 1969 or so, so learned to brush enamel pretty well and had at it. After a couple of years I heard about longboarding, so I decided a good sanding was in order, and started in making her smoooooth. I'm sanding away and all of a sudden I start to see nail heads and plank lines showing up white and freaked out (that is what you did in the late 60's early 70's, man). Thought maybe the boat was glassed over wood, because I knew nothing about molds. Eventually I realized they had just sanded a wooden Rhodes fair enough and made a mold off an existing wooden hull. My careful longboarding was just showing up the high spots.

I'll bet careful measurement would show all kinds of errors in any wooden carvel boat. We've come a long way, baby. This project is really fun to watch, and I'm glad the students are learning current best practices.

 

kimbottles

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I once asked Jim how we knew the deck would fit the hull and his reply: "Kim, it is all the same computer file, of course it will fit."
As a computer programmer, it drives me crazy how much people trust what comes out of a computer. (Even more than how they trust the computer, printer, internet connection, or copier to work every time and especially when they have a deadline.)
I don't trust computers I trust Jim Franken.

Jim is an expert at all of this. Before computers he was an expert at hand lofting. He hand lofted that Bill Garden designed 160' power boat for Orin Edson (Eviva?) (He is also a very good designer.)

He is very modest but Bob and I think he is a genius. He is very careful and measured and checks everything carefully.

If any of you ever decide to build a boat you would do very well to hire this guy.

Bob and I have a great crew working on this boat but if we had to pick just one guy to work with again it would be Jim (and I am not taking anything away from the rest of the crew who are all outstanding.)

And he is a very nice guy to boot. Just a delight to work with.

Kim

 

Jose Carumba

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Pugetopolis
I once had a consultation client who owned a well known semi production boat. He had becvome obsessed with the fact that his entire deck was off to one side as much as 4". He had 4" more side deck on one side than he had on the other. He liked the boat but he was worried about the asymetry. The builder reassurred him by telling him, "That's what you get when a boat is hand built." I didn't agree. I like precision. It would drive me crazy to think my mast was not centered over the keel.
There was an old boat builder turned boat building instructor at a local technical college who once said 'the difference between an amateur built boat and a professional built boat is that the amateur built boat is perfectly symetric'. I could see his point but didn't really agree with it. In my mind one should always strive for perfection. Today with all the advanced tools available to the designer and boat builder (CAD & CAM) you can get pretty close to perfect. Errors can still creep in though. Sometimes molds can change shape over time depending on where and how they are stored, etc.

 

viktor

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Jose, I helped loft Pizazz many years ago.It was ,as you know,the first big yacht built there. There were a few, as Fred called them,isims that got by everybody.Some bigger than others.But most isims can be tweked as you progress in the build.I think that boat came out just fine.

Kim, Thanks again for all the updates. Is the school ever open on weekends? I may be going up that way to visit some friends in the near future.

VIK

 

Great Red Shark

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Honolulu
Great pics of the roll-over, thank you. I've wanted to flip my 30-foot dagger-boarder over for years to do some re-coring but never have had the guts to do it.

As for symmetry - I think all boats are assymetrical, it's just a matter of the degree.

Supposedly one of the later California sleds (Taxi Dancer ? not sure) was built with a laser-sight in an attempt to produce a symmetrical hull. Don't know how well it succedded, but when you think about it - the boat on either tack is loaded up and heeled over in such a way as to be pretty asymmetric, so it's kinda moot.

Like a Sunfish's lateen rig - looks like it should suck on one tack, but anyone that's sailed one will tell you: it works just fine.

 

austin1972

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.... it's the same file....

Years ago when I built computers we had a bug in the floating point math hardware of the CPU.
Stupid floating point. We'd build analytic models in SAS and the 8.3 floating point wouldn't translate correctly from the SAS code to the JCL on the IBM system.

Not a huge discrepancy but for some reason they rounded differently and the models required perfection and the proofs would constantly fail. It was the bane of my existence for almost a year.

 

kimbottles

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Jose, I helped loft Pizazz many years ago.It was ,as you know,the first big yacht built there. There were a few, as Fred called them,isims that got by everybody.Some bigger than others.But most isims can be tweked as you progress in the build.I think that boat came out just fine.

Kim, Thanks again for all the updates. Is the school ever open on weekends? I may be going up that way to visit some friends in the near future.

VIK
Weekends are somewhat hit and miss. But if we can schedule the timing I may be able to meet you and open the shop so you can view the crew's handiwork. Maybe we can get Jose and others to join us and make it an event.

 

Jose Carumba

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Jose, I helped loft Pizazz many years ago.It was ,as you know,the first big yacht built there. There were a few, as Fred called them,isims that got by everybody.Some bigger than others.But most isims can be tweked as you progress in the build.I think that boat came out just fine.

Kim, Thanks again for all the updates. Is the school ever open on weekends? I may be going up that way to visit some friends in the near future.

VIK
Yes, P'Zazz turned out to be a great boat. You did a fine job lofting it. The problem with the hand lofted boats is getting the izms reported back to the design department so they can be incorporated into the drawings. If they don't, the next boat may have problems with fitting decks and bulkheads into it if you don't template them from the hull. With the plug CNC milled directly from the 3D model we can be assured that the mold will be exactly what we designed. Of course the izms have to be worked out in the computer during the design phase but fortunately that's easy to do. It still takes a practiced eye, even on the computer to see that everthing is fair but the tools make it easier.

Coincidentally you may be interested to know that as we speak the old P'Zazz mold is being torn apart so we can use the framework and rotating mechanism for a new mold. The plug parts (11 of them) are in the mill right now.

Edit: Kimb, I'd like to see it now that it is rolled over. Let's arrange something.

 
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kimbottles

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Edit: Kimb, I'd like to see it now that it is rolled over. Let's arrange something.

Maybe we should pick a date and invite all of the local CA/WLYDO people.

I will check with Bruce and see when they are starting the deck, might be interesting to see it underway too.

 

Hike Bitches!

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Well that sure looks a lot less exciting than the old school method of getting a whole lot of guys together and plying them with beer until they think they can lift a huge hull and flip it over... Sweet hull, the fun continues!
sculp, I think that is the point. In this day & age, we expect anything in pictures & 'film' (cell phone cam) to be a tragedy...when it all goes as planned, there is zero drama. No reward for the masses, just the MFO. B)

 

sculpin

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Well that sure looks a lot less exciting than the old school method of getting a whole lot of guys together and plying them with beer until they think they can lift a huge hull and flip it over... Sweet hull, the fun continues!
sculp, I think that is the point. In this day & age, we expect anything in pictures & 'film' (cell phone cam) to be a tragedy...when it all goes as planned, there is zero drama. No reward for the masses, just the MFO. B)
I know, and drama is highly over rated (unless the drama belongs to someone I don't like). As a kid we built a 23' day sailer, and the hull turning was quite the event.

 

Great White

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Bremerton, WA USA
Edit: Kimb, I'd like to see it now that it is rolled over. Let's arrange something.

Maybe we should pick a date and invite all of the local CA/WLYDO people.

I will check with Bruce and see when they are starting the deck, might be interesting to see it underway too.
I would sure like to view the progress too. And I am available during the week also.

 
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Hike Bitches!

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Solomons, MD
Well that sure looks a lot less exciting than the old school method of getting a whole lot of guys together and plying them with beer until they think they can lift a huge hull and flip it over... Sweet hull, the fun continues!
sculp, I think that is the point. In this day & age, we expect anything in pictures & 'film' (cell phone cam) to be a tragedy...when it all goes as planned, there is zero drama. No reward for the masses, just the MFO. B)
I know, and drama is highly over rated (unless the drama belongs to someone I don't like). As a kid we built a 23' day sailer, and the hull turning was quite the event.
Hell, just flipping a Lightning hull or a Bucaneer hull can be an event around here. :eek:

 
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