kimbottles

Perry Sliver Class Day Sailor

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This is way too complicated. I have a (~1975?) Johnson 6 you can use.

 

It works for all the boats in Ontario. Don't see why you guys should be any different.

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I guess Bob already considered this, but why not a caterpillar drive?

 

Because you need a nuke reactor to power one.

 

40-mr_fusion.jpg

 

 

Doc tossed in a banana peel and some beer for fuel.....might be a problem there.

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So you have harvest and cows/steers? Sounds like a lot of work to me. I still have my cow fantacy going. If I ever move off the beach I'll move inland into dairy farm country. I'd like a house next door to a dairy farm so I can watch.

 

Here' s a pic of Point Reyes National Seashore complete with cows and ocean - you can have it all!

 

http://m.flickr.com/photos/stwiso/3235224709/lightbox/

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No...I am very behind when it comes to most pop culture references, with a few exceptions.

Brodie, that is funny because my 42 year old son says I am completely disconnected from contemporary culture!

 

But I did both read and see "Hunt for Red October" so I knew what a "Caterpillar drive" was...........never considered it on a "simple" vessel.

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Kim and I were at the yard this morning at 9am. By 11am the keel was back on the boat and a travel lift dropped the FRANCIS LEE into the drink for the very first time.

It was exciting.

 

The slings stayed in place but the boat was floated so we could check the flotation.

We have a few itemns to add yet, like: the rig, batteries, fluids misc gear, sails but we appear to be spot on for trim and floating just a bit light. We might get lucky and come in exactly at the designed weight or slightly less. We will not be heavy.

 

Can't say I was tremendously worried but you always are a bit nervous when a new boat is splashed for the first time.

Kim and I had to leave the yard to give a tag team talk to the PNW CCA chapter at SYC. I get very nervous at these talks. It was very nice to be doing it right after seeing the FRANCIS LEE float. It almost gave me confidence.

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Wow! That is always a special moment, especially for the designer when the client is standing right at his side... Congrats to all, what a sweet craft, it will grace our waters for generations to come.

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Kim and I were at the yard this morning at 9am. By 11am the keel was back on the boat and a travel lift dropped the FRANCIS LEE into the drink for the very first time.

It was exciting.

 

The slings stayed in place but the boat was floated so we could check the flotation.

We have a few itemns to add yet, like: the rig, batteries, fluids misc gear, sails but we appear to be spot on for trim and floating just a bit light. We might get lucky and come in exactly at the designed weight or slightly less. We will not be heavy.

 

Can't say I was tremendously worried but you always are a bit nervous when a new boat is splashed for the first time.

Kim and I had to leave the yard to give a tag team talk to the PNW CCA chapter at SYC. I get very nervous at these talks. It was very nice to be doing it right after seeing the FRANCIS LEE float. It almost gave me confidence.

Congratulations, Kimb and Bob.

 

Any pics of FL's first splash?

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Hey Bob, Kim, You two are old hands here, you know the rules. Photos or it didn't happen!

 

Ah well, it probably did happen. Congratulations!

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What, did the bars just close there?

 

 

Edit: Never mind, Sculpin deleted his post so this makes no sense.

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Conga rats Kim! Bob, you had any doubts?

There were Conga rats at the launch? Wow! :)

 

Congrats Bob and Kim, great to get to that milestone!

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Been kind of busy today with non boat stuff.

 

A couple nice Kiwi sailors I know stopped by to see the project.

post-8115-0-41142700-1381806693_thumb.jpg

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Oh yeah, the boat floats on her lines. (I knew it would be OK when I saw Bob parking his car nose in instead of nose out for a quick getaway.)

 

She was floating a few inches high but nicely trimmed, but she is not yet fully loaded or assembled so she will sink another inch or so later on (but her batteries are installed and on board already.)

 

This vessel will come in light so I will be able to allow SWMBO to add a few items later on.....maybe.

 

Bob and I were confident, but it is always great to have it all turn out well anyway.

 

Another anticlimactic moment in the Sliver project. (We have had a string of very satisfying anticlimactic moments with this project.)

 

After she came back out of the water we checked the wet line around her and it was even, level and symmetrical, kind of hard to ask for more than that!

 

 

 

 

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post-8115-0-98879300-1381806997_thumb.jpg

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Congrats, Kim. Good job, Bob.

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Jordan took one for the team when the wrench he was holding while they tightened the keel bolts slipped and kissed the bridge of his nose......one stitch and some super glue. But he was right back working on the boat like the trooper he is.....

post-8115-0-41432600-1381809396_thumb.jpg

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I guess Bob already considered this, but why not a caterpillar drive?

 

Because you need a nuke reactor to power one.

 

40-mr_fusion.jpg

 

 

Doc tossed in a banana peel and some beer for fuel.....might be a problem there.

 

He wasted beer?

 

Cheers

Craig

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Oh yeah, the boat floats on her lines. (I knew it would be OK when I saw Bob parking his car nose in instead of nose out for a quick getaway.)

 

She was floating a few inches high but nicely trimmed, but she is not yet fully loaded or assembled so she will sink another inch or so later on (but her batteries are installed and on board already.)

 

This vessel will come in light so I will be able to allow SWMBO to add a few items later on.....maybe.

 

Bob and I were confident, but it is always great to have it all turn out well anyway.

 

Another anticlimactic moment in the Sliver project. (We have had a string of very satisfying anticlimactic moments with this project.)

 

After she came back out of the water we checked the wet line around her and it was even, level and symmetrical, kind of hard to ask for more than that!

Kim - 2 questions:

 

1) what's up with the color balance of your photographic device?

 

2) when did you go to a forward cockpit and companionway? Looks like it might be wet in a breeze ;-)

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Fairing in the keel flange looks like it's going to be a lot of F_U_N!

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Fairing in the keel flange looks like it's going to be a lot of F_U_N!

 

Lots of bog but remember, the keel pan is recessed so really they'll just have to full it up and fillet the corners. From a (much) earlier post by Kim:

 

http://forums.sailinganarchy.com/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=163186

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The keel bolts have nuts welded on the lower end.

 

Sal is correct. The solid grp pan is recessed so they just have to fill the recess to fair it in.

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Oh yeah, the boat floats on her lines....

Kim - 2 questions:

 

1) what's up with the color balance of your photographic device?

...

 

Woo hoo! That's a big day, even if the result was expected.

 

He's using an iPhone. Kim, in case you don't know, you can tap the screen anywhere and the phone camera will focus and set brightness for that area. Tap around in different light or dark areas when framing a shot and it will change settings.

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What a great milestone. Congratulations!! Like flying, uneventful is a good thing in this context!!

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Oh yeah, the boat floats on her lines. (I knew it would be OK when I saw Bob parking his car nose in instead of nose out for a quick getaway.)

 

She was floating a few inches high but nicely trimmed, but she is not yet fully loaded or assembled so she will sink another inch or so later on (but her batteries are installed and on board already.)

 

This vessel will come in light so I will be able to allow SWMBO to add a few items later on.....maybe.

 

Bob and I were confident, but it is always great to have it all turn out well anyway.

 

Another anticlimactic moment in the Sliver project. (We have had a string of very satisfying anticlimactic moments with this project.)

 

After she came back out of the water we checked the wet line around her and it was even, level and symmetrical, kind of hard to ask for more than that!

Kim - 2 questions:

 

1) what's up with the color balance of your photographic device?

 

2) when did you go to a forward cockpit and companionway? Looks like it might be wet in a breeze ;-)

iPhone 5 have no idea how to change color, am not a photographer

 

Edit: Just read the post about tapping the screen, I will try it.

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I have also found on my iPhone 5 that it is pretty easy when you are going about life shooting snapshots to get the iPhone camera into one of the effects without really trying, so if the touching of the screen (you need to touch and hold for that other effect by the way) doesn't work, tap on those 3 circles on the bottom right of the screen, and then tap on the middle box, which puts you in normal mode.

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Kim-

 

First off, thanks so much for sharing this process with the lot of us. (After enjoying this thread for over a year, that was long overdue.)

 

Second, I think your iPhone is, indeed, applying a filter to your photos. (You can see an example of them here.) When you've got your camera app open, look to the right of the shutter button (if you're holding the phone vertically) for the icon of three entwined circles. If you tap it, I believe the screen will show nine filtered versions of the view. Your pics look like they're getting the 'Process' filter. Select the center option to go back to shooting with no filter. Hope that helps.

 

-J

 

 

edit- Oops. Hadn't refreshed before nroose posted.

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Been kind of busy today with non boat stuff.

 

A couple nice Kiwi sailors I know stopped by to see the project.

 

Well that explains a lot.....always thought Arne had Norski blood!

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The keel bolts have nuts welded on the lower end.

 

Sal is correct. The solid grp pan is recessed so they just have to fill the recess to fair it in.

Keel Pan recessed well into the hull......

post-8115-0-02732000-1381856289_thumb.jpeg

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Been kind of busy today with non boat stuff.

 

A couple nice Kiwi sailors I know stopped by to see the project.

 

Well that explains a lot.....always thought Arne had Norski blood!

Arne was the token non Kiwi in the photo, Bruce and Doug are the Kiwis (and very nice guys to boot!

 

I have also found on my iPhone 5 that it is pretty easy when you are going about life shooting snapshots to get the iPhone camera into one of the effects without really trying, so if the touching of the screen (you need to touch and hold for that other effect by the way) doesn't work, tap on those 3 circles on the bottom right of the screen, and then tap on the middle box, which puts you in normal mode.

Thanks, will do.

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The keel bolts have nuts welded on the lower end.

Welded nuts

Out of interest, what are the advantages of welding a nut over buying a bolt? Are bolts this size difficult to obtain for less than a king's ransom? Or just plain difficult to obtain? Or is there an engineering benefit?

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I love seeing boats (and other stuff, too) being designed and built. Thank you Messrs. Bottles and Perry for all you've shared with us here. It's wonderful seeing the boat actually floating in the water - much sooner than I anticipated. I'm looking forward to seeing it sail. How soon will the shakedown be?

 

Romain

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The keel bolts have nuts welded on the lower end.

Welded nuts

Out of interest, what are the advantages of welding a nut over buying a bolt? Are bolts this size difficult to obtain for less than a king's ransom? Or just plain difficult to obtain? Or is there an engineering benefit?

 

Bolts in Aquamat 22 did not seem to be available in the exact lengths we needed (at least I could not find any locally) and Pacific Fishermen had A22 shafts in stock so easy to get them in a day or so.

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The keel bolts are Aquamet I think. Google "aquamet bolt" and you don't get anything so I suppose this was the only way to go. I don't remember what the nuts are.

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Nice to see a picture of my boy! I thought he might get black eyes... Hopefully, no blood on the boat!

Jordan took one for the team when the wrench he was holding while they tightened the keel bolts slipped and kissed the bridge of his nose......one stitch and some super glue. But he was right back working on the boat like the trooper he is.....

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The keel bolts are Aquamet I think. Google "aquamet bolt" and you don't get anything so I suppose this was the only way to go. I don't remember what the nuts are.

 

How cool! Does the welding effect the strength?

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I think i is going for some effects with his photography. Kind of a Halloween look.

And not one shot of me wearing a tie?

Too Scary.

 

Kim, thanks for the keel-pan pic of the hull - seems a LOOOOOOONG time ago now, with the strips just being planked up. So much Epoxy ago. But it's sure all coming together nicely now.

 

Thanks, all.

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How soon will the shakedown be?

 

Romain

 

When CSR finishes the boat and the sail maker finishes the sails......late Nov??

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The keel bolts are Aquamet I think. Google "aquamet bolt" and you don't get anything so I suppose this was the only way to go. I don't remember what the nuts are.

 

I have seen it spelled both ways: aquamat and aquamet.......spell check does not like either......

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Been kind of busy today with non boat stuff.

 

A couple nice Kiwi sailors I know stopped by to see the project.

Did anybody mention AC34? :angry:

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Been kind of busy today with non boat stuff.

 

A couple nice Kiwi sailors I know stopped by to see the project.

Did anybody mention AC34? :angry:

They are both very experienced and accomplished professional sailors. Although they would have liked to get the Cup back down to Kiwi land, they both expressed admiration for the comeback and they both said SF was the best sailing venue in the world and much better than Auckland. Gracious classy guys both of them. Bruce MacPherson and Doug Christie (good Scots names!)

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Bruce MacPherson and Doug Christie (good Scots names!)

Brucey!! That's a party walking on two legs, for certain. He also owns the freshest produce/fruit stand in West Seattle.

 

Top bloke. I suppose Doug Christie is a fair guy, too, at least by standing that close to Bruce.

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Bruce MacPherson and Doug Christie (good Scots names!)

Brucey!! That's a party walking on two legs, for certain. He also owns the freshest produce/fruit stand in West Seattle.

 

Top bloke. I suppose Doug Christie is a fair guy, too, at least by standing that close to Bruce.

 

Fearless MacPherson we call him based on some of his sailing exploits.......maybe the best sailor I have had aboard, surely one of the most energetic and fun guys around!

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So when about is the loosely projected day for a sea trial?

 

Looks absolutely beautiful, but without a rig i half expect either a giant with a double paddle to take it for a spin or a guy with a big drum and a company of Vikings to row it off to a distant battle.

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So when about is the loosely projected day for a sea trial?

 

Looks absolutely beautiful, but without a rig i half expect either a giant with a double paddle to take it for a spin or a guy with a big drum and a company of Vikings to row it off to a distant battle.

 

See #7449

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The keel bolts are Aquamet I think. Google "aquamet bolt" and you don't get anything so I suppose this was the only way to go. I don't remember what the nuts are.

 

How cool! Does the welding effect the strength?

Yes, but as it is just a locking weld on the end of the stud, the heat affected zone (where the weld has changed the material properties) is quite small, and the stud/nut connection should retain most of its strength. If it had been a stud structurally welded onto the keel plate it would be a different story, with the heat affected zone right in the highest stressed area.

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Jordan...simple advice...impact wrench. Be easy with it, but use it. A torque socket kit extension is a wonderful tool.

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When the day arrives. I would love to see a shot from a few boat lengths back off the leeward corner with the leeches perfectly lined up while FL power reaches away. Something spiritual for me about that view of a pretty sailboat.

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When the day arrives. I would love to see a shot from a few boat lengths back off the leeward corner with the leeches perfectly lined up while FL power reaches away. Something spiritual for me about that view of a pretty sailboat.

Thats the same view the wind sees, except from the other end.

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Bob, Kim.

 

Looks like you missed a trick going for only two bows. Should have gone whole hog with three.

 

 

(It's art, apparently. Even so, looks like a nice bit of clinker boat building, even with a ply floor. The cynic in me wonders about finances.)

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When the day arrives. I would love to see a shot from a few boat lengths back off the leeward corner with the leeches perfectly lined up while FL power reaches away. Something spiritual for me about that view of a pretty sailboat.

Yes, I agree.

 

Kim & Bob , it looks fantastic. So nice to see pics of it dipped into the water. It looks very much as it "belongs" there. It appears to be waiting patiently, longing to be given it's "wings", so it can fly stealthly through the water. Gorgeous design.

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Just realized we splashed Kim's boat in fresh water. So,,,we are 449 lb.s lighter than I thought. Or, we will float.246" higher in salt water.

Lighter is always better at this stage.

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Just realized we splashed Kim's boat in fresh water. So,,,we are 449 lb.s lighter than I thought. Or, we will float.246" higher in salt water.

Lighter is always better at this stage.

 

Time to redo the waterline....

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IB:

No, that's precisely my point. We will come in within an RCH of the designed DWL.

But I'll assume, considering the source, that you are joking.

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Just realized we splashed Kim's boat in fresh water. So,,,we are 449 lb.s lighter than I thought. Or, we will float.246" higher in salt water.

Thought: you splashed in that dreamy stretch of the Cut contaminated by industrial-strength Ballardium. That shit is so dense its molecular weight is equivalent to Scott Anderson's bank balance (about 7 Billion, +/-).

 

Thus, the boat is about a fifth of Scotch heavy. Drink the Scotch, 'overboard' it, and hit the marks you designed.

 

Coincidentally, .246" = 7 Billion RCHs. Fact.

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You can't calculate RCH equivalents without another dimension. Simple math, i.e. .246" by ? It's a two dimensional problem.

I keep RCH's as an absolute and I don't convert them. I like them clean.

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You can't calculate RCH equivalents without another dimension. Simple math, i.e. .246" by ? It's a two dimensional problem.

I keep RCH's as an absolute and I don't convert them. I like them clean.

 

And red apparently...

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You can't calculate RCH equivalents without another dimension. Simple math, i.e. .246" by ? It's a two dimensional problem.

I keep RCH's as an absolute and I don't convert them. I like them clean.

 

And red apparently...

 

You know some RCH's that aren't red?

 

Age?

 

I never thought that about you. That's a little kinky.

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Oh yeah, the boat floats on her lines. (I knew it would be OK when I saw Bob parking his car nose in instead of nose out for a quick getaway.)

 

She was floating a few inches high but nicely trimmed, but she is not yet fully loaded or assembled so she will sink another inch or so later on (but her batteries are installed and on board already.)

 

This vessel will come in light so I will be able to allow SWMBO to add a few items later on.....maybe.

 

Bob and I were confident, but it is always great to have it all turn out well anyway.

 

Another anticlimactic moment in the Sliver project. (We have had a string of very satisfying anticlimactic moments with this project.)

 

After she came back out of the water we checked the wet line around her and it was even, level and symmetrical, kind of hard to ask for more than that!

 

Congrates, I new there was a good reason to check in.

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"You can't calculate RCH equivalents without another dimension. Simple math, i.e. .246" by ? It's a two dimensional problem.

I keep RCH's as an absolute and I don't convert them. I like them clean."

 

Huh? What?

 

Soo does that mean that the fairing stays on the bulb will not have to be removed to add more lead?

 

Kidding

 

6mm will get taken up up by things SWMBO finds necessary, and will be right.

 

FD

 

edit to add quotes from Bob

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Having never sailed one, I have a question for the folks who have experience on boats with the contemporary thin blade/bulb keels like FL has.

 

Do they need to be moving at a bit of (or substantial) speed to develop some lift to provide lateral resistance or is there enough lateral plane to resist leeway even at minimal speed through the water?

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Jon, Jon, Jon:

Look at how much pure fin FL has and compare it to most production boats. This is a 10' draft boat with plenty of planform aea in the fin. It's not a blade thin, short chord fin. Every keel needs some leeway to begin generating lit. That's where angle of attack comes from. No angle of attack on a symetrical foil means no lift. A fin like this will develope lift very quickly. Whie it is not a huge fin in terms of square footage of planform it's still a big fin with a very efficient geometry. And that is why you see it on the FL.

 

What do you expect me to say, "Holy cow, now you mention it I don't think it's going to work at all. The boat's just going to go sideways!"

" I should have thought of that. Damn it."

 

You see Jon, I cheated. I used a little program called a VPP program that intergrates the appendages and their charcateristics with the hull and quite accurately predicts performance over a wide range of conditions.

If there has been an inadquacy with the keel fin this would have been evident in the VPP data. You would have seen it on the polars. I don't do any new designs without VPP data these days. We do not have to guess anymore.

 

It occurs to me that I haved two of my boats with more radical keels than the one FL has. That would be the 65' ICON that draws 13.8' with the keel down and the FT10m that draws 7.62' keel down. I am unaware of any different feeling you get when to tack either of these boats in light air other than the fact that they go fast quickly and both boats are renouned for their light air speed.

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Jon:

I think I may have left out a key element to helping you understrand how a keel like FL's works so well.

 

The foil choice is controlled to a large degree by the pragmatic consideration of what structure you need in the fin to take the bending loads of the heavy bulb.

 

The mom and pop low spect ratio production boat racer/cruiser keel will usually have a fairly thin foil. Maybe with a thicknes ratio aas low as 10% to reduce frontal area. There is plenty of volume in the fin to get in the required lead due to the ample planform.

 

But the high spect ratio keel like FL's has to go to a thicker foil in order to get in the fin structure. In a keel like this you might see a thickness ratio as high as 14%. Could be higher. Designers are pretty secretive about this ratio.This gives you a very good foil for delivering lift at low speeds.

 

You can't use 14% on the low aspect ratio fin. It would be just too fat a keel given the relatively long chord length. I used 14 % on the Norseman 447 because initially I was going to stick the engine down in the top of the fin. That's the thickest keel I have done with that type aspect ratio. I would prfer 12% for that kind of keel. So with the vertcial leading edge or near vertical leading edge, the high aspect ratio and coupled with the thicker foil you have a very efficient keel.

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Jon, Jon, Jon:

Look at how much pure fin FL has and compare it to most production boats. This is a 10' draft boat with plenty of planform aea in the fin. It's not a blade thin, short chord fin. Every keel needs some leeway to begin generating lit. That's where angle of attack comes from. No angle of attack on a symetrical foil means no lift. A fin like this will develope lift very quickly. Whie it is not a huge fin in terms of square footage of planform it's still a big fin with a very efficient geometry. And that is why you see it on the FL.

 

What do you expect me to say, "Holy cow, now you mention it I don't think it's going to work at all. The boat's just going to go sideways!"

" I should have thought of that. Damn it."

 

You see Jon, I cheated. I used a little program called a VPP program that intergrates the appendages and their charcateristics with the hull and quite accurately predicts performance over a wide range of conditions.

If there has been an inadquacy with the keel fin this would have been evident in the VPP data. You would have seen it on the polars. I don't do any new designs without VPP data these days. We do not have to guess anymore.

 

It occurs to me that I haved two of my boats with more radical keels than the one FL has. That would be the 65' ICON that draws 13.8' with the keel down and the FT10m that draws 7.62' keel down. I am unaware of any different feeling you get when to tack either of these boats in light air other than the fact that they go fast quickly and both boats are renouned for their light air speed.

 

Thanks Bob. I wasn't suggesting that the keel wouldn't work properly - obviously it will. I was simply curious if keels like that had to be moving to avoid a lot of leeway due to having so little surface in the water - sort of like the way boats with high freeboard behave during slow speed maneuvering.

 

I have no experience with those new style keels and I've heard some stories.... which is what triggered the question.

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I can only add that from personal experience, extreme keels - like the foil on the Melges 24, CAN get more than a little Stall-y at very low speeds. - it's quite easy to loose steerage at very low speeds, and thus you are well advised to keep the thing moving well (above 2 kts) in order to 'track' well in crowded spaces (starting lines, dock fairways under sail). That is the price for low drag that yields the high speeds, I suppose.

 

I don't see this as a factor with FL - I believe her length will assist in tracking where the bottom of the Melges is kinda 'gripless' in comparison.

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Jon, Jon, Jon:

Look at how much pure fin FL has and compare it to most production boats. This is a 10' draft boat with plenty of planform aea in the fin. It's not a blade thin, short chord fin. Every keel needs some leeway to begin generating lit. That's where angle of attack comes from. No angle of attack on a symetrical foil means no lift. A fin like this will develope lift very quickly. Whie it is not a huge fin in terms of square footage of planform it's still a big fin with a very efficient geometry. And that is why you see it on the FL.

 

What do you expect me to say, "Holy cow, now you mention it I don't think it's going to work at all. The boat's just going to go sideways!"

" I should have thought of that. Damn it."

 

You see Jon, I cheated. I used a little program called a VPP program that intergrates the appendages and their charcateristics with the hull and quite accurately predicts performance over a wide range of conditions.

If there has been an inadquacy with the keel fin this would have been evident in the VPP data. You would have seen it on the polars. I don't do any new designs without VPP data these days. We do not have to guess anymore.

 

It occurs to me that I haved two of my boats with more radical keels than the one FL has. That would be the 65' ICON that draws 13.8' with the keel down and the FT10m that draws 7.62' keel down. I am unaware of any different feeling you get when to tack either of these boats in light air other than the fact that they go fast quickly and both boats are renouned for their light air speed.

 

Thanks Bob. I wasn't suggesting that the keel wouldn't work properly - obviously it will. I was simply curious if keels like that had to be moving to avoid a lot of leeway due to having so little surface in the water - sort of like the way boats with high freeboard behave during slow speed maneuvering.

 

I have no experience with those new style keels and I've heard some stories.... which is what triggered the question.

I suspect we will have to avoid "pinching" when we first come out of a tack, but once we have any speed on I bet she points pretty high, and being light she should be able to obtain that speed fairly quickly. The joy of this kind of design just might be that her extra speed will allow her to do a number of things well.

 

I am very curious as to how she handles, I know she will handle very well, just might have little characteristics unlike some of my previous vessels. (I suspect she will sail much like my Swede 55 or my 30 square metre boat. Just faster, especially when sailed backwards.)

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I'm sorry Jon, I'll give this another shot:

You ask if anyone has had experience sailing a boat with a keel like this. I have. I would have to hear very specific stories associated with very specific boats before I paid attention. I'd also want to know who was telling the story. Lots of poor sailors can stop a boat in light air.

 

Look at the race records for the FT10m and ICON. Look hard when the races are in light air. Those boats and very effective even dominant in light air. If were going to race this weekend and I knew it would be light and I could pick my boat, I'd take an FT10m. So if there is some kind of keel anomaly going on it's a very good one and I like it. Given the design characteristics of this particular keel, I can't speak for the Melges, I expect it to perform very well in light air. The nice, thick foil should prevent it from being "stally". I'd associate "stally" with a thin fin. We don;t have that.

 

Of course if you are trying to optimize performance in light air manouvering you do not pinch coming out of a tack. You don't do that in any boat in light aiir. Do you? You tack gradually so as to maintain as mch boat speed as possible. You sail the boat "fat", i.e. gennny or jib not jammed in, to let the boat build up some speed, you get the keel lifting and then slowly bring it up on the wind when you have the boat speed. Pinching out of a tack in light air is the kiss of death on any boat.

 

Jon, you also associate high freeboard with problems manouvering in light air. This I don't understand. In heavy air freeboard would be a problem but not in light air.

I'll give you two examples, not stories. I did a two tonner HEATHER for Seattle conditions. I did a quarter tonner UNION JACK for Seattle conditions. In Seattle both boats were unbeatable. YACHTING magazine wrote an article giving credit to HEATHER for "destroying Class A Racing in Seattle". I can say with fair certainty that HEATHER won every race in the PNW. One way I gave them boat speed in light ir was to give them tall rigs. One way I made the tall rigs even taller was to give the boats high freeboard. There is more wind the higher you go. The IOR gave you benefit for high freeboard and I knew in light air freeboard would never be problem. BINGO a sistership to UNION JACK is still consistantly winning in Puget Sound in light air. I think a few people posting here have experience with BINGO. Having sailed both boats I can assure you that their freeboard has never been a problem.

 

An image I have of HEATHER that I will never forget is a race start postponed, the boats all floating around with no way on, drifting. But up and down the start line sailed HEATHER, steaming along under full control. I'm sorry I don't have any digital images for HEATHER.

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I apparently didn't explain myself very well with the original question but I think I got my answer anyway. What I was wondering was if the new type of deep, short chord keels provided enough planform area to prevent excessive leeward drift at no or very low boat speeds or if the boats needed flow and the lift thus generated to prevent excessive leeway. I was thinking about situations like screwing up a tack and losing speed - would you get more leeway than a more conventional or older style keel before getting some speed back on?

 

Basically I was wondering if this style of boat and keel had unique "driving" requirements. Old, very full keels are notorious for being troublesome to tack in light winds, my own boat has a very high clipper bow and even though it's cut away underwater, any hesitation or delay in tacking will blow it - the bow will get blown back. I just wondered if the new keels had some sort of handling quirks of their own the way those older style boats did.

 

As to freeboard - I was referring to low speed maneuvering, like at gas docks, in marinas or other restricted areas, not light winds.

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Jon:

Maybe a place to start would be an accurate and objective comparisons of planform areas. I think you would be surprised. This would be better than assumptions. I'll bet that if you calculate the planform area of a typical mom and pop production boat of today you will find that it has LESS planform area than a deep, high aspect ratio keel.

 

Do you really, I mean truly, think that if there were some design flaw for performance in these keels you would be seeing them on every state of the art racing boat today?

Sometimes you just have to resign yourself to the fact that the old guys, and I rever most them, were wrong. They had limited tools, Some day some kid designer will look at my work and say, "It was interesting and wrong but he had limited tools".

 

But I think that basic steering techniques will be the same in this boat as in any other boat. It's a sensitivity thing. You feel what the boat is doing, you know what it likes and you do it. I do it like that.

I think the older style boats like yours have a plethora (We bought you a sweater El Guapo) of handling challenges because so much of the design is a ,,,,,,,,,,,,bit off. Not much science in those boats. No Vpp's. No understanding of foil behavior. But they can look marvelous and be fun family boats. I love traditional designs. I just draw a very distinct line between the traditional boat and a boat like ICON.

 

Problems with freeboard around gas docks is windage. That's all. Windage. This has zero to do with foils. But if I apprach this from a different angle I think you raise a good point. An older style boat like a Westsail, while it has plenty of freeboard and windage, it also hase a huge planform full keel under it. I would think that a high freeboard but with a full keel would be less bothered at the gas dock than a high freeboard boat with minimal planform under the water. It's a drag thing. It's harder to turn the full keel boat around with windage. Of course it's also harder to turn the full keel boat around when you want to turn it around. By virtue of all that planform the full keel boat does not want to turn. That can make approaching the gas dock an adventure.

 

It's a mixed bag. If gas dock windage is a valid criteria for you then go for it.

"Hey baby, did you see me manouvering at the gas dock today?"

 

I'll go to my room.

Wait a minute! I'm in my room.

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I grew up sailing a full keel Herreshoff 12 1/2, and then for about 10 years up until last winter, I owned an Ultimate 24. The high aspect foils are better at preventing leeway, but then on some boats there will be times when the foils stall. If you are maneuvering slowly in close quarters and get a gust, or if you are beam reaching in very light air with a spinnaker up that isn't efficient at those angles and get a gust, you can just go sideways. These things don't happen often, and probably the Francis Lee will be pretty immune due to her (?) long narrow hull... But the takeaway is that the high aspect foils are MORE efficient and result in LESS leeway under almost all conditions.

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Do you really, I mean truly, think that if there were some design flaw for performance in these keels you would be seeing them on every state of the art racing boat today?

Sometimes you just have to resign yourself to the fact that the old guys, and I rever most them, were wrong. They had limited tools, Some day some kid designer will look at my work and say, "It was interesting and wrong but he had limited tools".

 

.

 

That was what I didn't get across - I wasn't trying to say that I thought there was a "design flaw" in these new foils, obviously their overall performance is better than older designs. I was simply curious if they behaved differently or had unique handling characteristics compared to older shapes - like the Peterson trapezoid for example. I think the comments some posters have made about stall characteristics is really the answer to what I was asking. I DID assume a smaller planform than "conventional" fin keels was the norm, for reduced wetted surface and I also DID assume the foils would be more critical (thinner).

 

Learned something about both those points.

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Sloop, your question was well asked and has been well answered, Bob can be straight to the point sometimes, It's his way, I like that about him.

I don't see the the need to defend your question, I've learned a lot from your question and the answers Bob and others have given

 

FD

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Questions like that are good. They get me thinking and I suspect they get a lot of others thinking too. Thinking is good.

I think the bottom line to my answer is that there is far more to keel design and keel performance than the two dimensional profile of the planform.

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