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Paul Pless
08-16-2018, 07:15 PM
Uffa. . .

21418

21419

21420

Yeadon
08-16-2018, 07:44 PM
Swoon

Hugh Conway
08-16-2018, 07:54 PM
Very nice. Need to build one, someday.

So, the ceiling clamps. Where, in what trade did they originate? Felibien in the 1600s called it a goberge
https://www.popularwoodworking.com/wp-content/uploads/felebien10_detail-663x1024.jpg
Modern luthiers call them "gobars". Where'd they come from?

ahp
08-16-2018, 09:15 PM
I wonder how Nezmuc's (sp?) 18 pound canoe was built, about 1900?

Hugh Conway
08-16-2018, 09:19 PM
I wonder how Nezmuc's (sp?) 18 pound canoe was built, about 1900?

nessmuk. rushton canoe c. 1880. https://journals.lib.unb.ca/index.php/MCR/article/view/17788/22168

moTthediesel
08-16-2018, 10:01 PM
nessmuk. rushton canoe c. 1880. https://journals.lib.unb.ca/index.php/MCR/article/view/17788/22168

Seeing those shots of the Uffa Fox dingy, my first thought as well was of Henry Rushton. I’m sure Fox was also influenced by the work of England’s many racing shell builders as well.

Peerie Maa
08-17-2018, 05:03 AM
Very nice. Need to build one, someday.

So, the ceiling clamps. Where, in what trade did they originate? Felibien in the 1600s called it a goberge
https://www.popularwoodworking.com/wp-content/uploads/felebien10_detail-663x1024.jpg
Modern luthiers call them "gobars". Where'd they come from?

Still used by Norwegian boat builders to control plank deadrise.

Rob Hazard
08-17-2018, 05:25 AM
That photo is listed as being Avenger, which was launched in 1928. She is widely regarded as the first true planing sailboat, though I know we've had heated discussions about that on this very forum...

Go-sticks or go-bars have been in use for centuries in harpsichord and piano building, for assembling soundboards, as well as pipe organ building, for making wind chests.

Keith Wilson
08-17-2018, 07:45 AM
Nice photo. Wood selection seems pretty critical. Impressive, but it really seems he's trying to get wood to do something it doesn't do all that well; the mirror image of trying to build a 1000-foot tanker out of wood.

I think props from the ceiling have been used since about three days after human beings started working in buildings with roof beans strong enough to stand the force. Or maybe in caves, before that.

John Meachen
08-17-2018, 02:57 PM
I think for a more objective view of the traditional 14 you might ask Andrew Craig-Bennet how much fun it was varnishing the interior of such a boat.It does look nice finished.I have never seen any mention of a connection to Rushton,but it is important to remember that Uffa served an apprenticeship with S.E. Saunders who were very good builders of early hydroplanes and seaplanes.

Peerie Maa
08-17-2018, 03:09 PM
Seeing those shots of the Uffa Fox dingy, my first thought as well was of Henry Rushton. I’m sure Fox was also influenced by the work of England’s many racing shell builders as well.

I would not bank on it. The stresses that the different hulls are exposed to bare no comparison. Shells have a very different framing regime and may well have been skinned differently.

oznabrag
08-17-2018, 03:12 PM
I think for a more objective view of the traditional 14 you might ask Andrew Craig-Bennet how much fun it was varnishing the interior of such a boat.It does look nice finished.I have never seen any mention of a connection to Rushton,but it is important to remember that Uffa served an apprenticeship with S.E. Saunders who were very good builders of early hydroplanes and seaplanes.

Mr. Craig-Benet (SP?) should explore the joys of airless spraying.

:D

I recently had occasion to paint two louvered doors, and decided that the brush was the go, simply because I didn't have enough of the required paint to fill my rig and deliver the product.

If I were to tackle varnishing the interior of that Fox dinghy, I would definitely run the sprayer.

10 minutes per coat tops, plus cleanup.

John Meachen
08-17-2018, 03:23 PM
It isn't the varnishing that takes the time in my experience.The rubbing down is a nightmare.

Keith Wilson
08-17-2018, 03:24 PM
If I were to tackle varnishing the interior of that Fox dinghy, I would definitely run the sprayer.Puttin the finish on is rarely the problem. Taking it off once it's started to peel doesn't bear contemplating.

oznabrag
08-17-2018, 03:30 PM
I don't want a Fox dinghy.

Gerarddm
08-17-2018, 03:49 PM
George Pocock racing shells from red cedar.

johnw
08-17-2018, 04:10 PM
That photo is listed as being Avenger, which was launched in 1928. She is widely regarded as the first true planing sailboat, though I know we've had heated discussions about that on this very forum...

Go-sticks or go-bars have been in use for centuries in harpsichord and piano building, for assembling soundboards, as well as pipe organ building, for making wind chests.
Sounds like an invitation to the 'no true Scotsman' fallacy.

According to Fox, if it was blowing hard enough, all the 14s would plane, but in the usual conditions, only Avenger would plane. So how 'true' does it need to be to qualify as a 'true planing dinghy?' Avenger was revolutionary, that should be enough.

Chris Smith porter maine
08-17-2018, 05:21 PM
nessmuk. rushton canoe c. 1880. https://journals.lib.unb.ca/index.php/MCR/article/view/17788/22168

That was a bit of gold thank you Hugh.

Chip-skiff
08-18-2018, 12:30 AM
The Kiwis were building and racing, fast, light sailboats long before Uffa Fox drew his first plan.

https://teara.govt.nz/files/p7132ar.jpg

There was a really good thread on the History of the Planing Dinghy that went for many pages. Just searched for it without success.

https://waitematawoodys.files.wordpress.com/2015/10/patiki-kahurangi.jpg

Andrew Craig-Bennett
08-18-2018, 02:29 AM
Tell me about it...

https://s20.postimg.cc/n5rd15ood/FEAF1B46-0902-4BED-8F7A-1DF20BCD1ED3.jpg (https://postimg.cc/image/pzuielquh/)


https://s20.postimg.cc/wunewivnh/1C4B4C04-5DB1-4BE8-AE3E-58F413BBE182.jpg (https://postimg.cc/image/kg0mw7455/)

Peerie Maa
08-18-2018, 03:24 AM
The Kiwis were building and racing, fast, light sailboats long before Uffa Fox drew his first plan.

https://teara.govt.nz/files/p7132ar.jpg

There was a really good thread on the History of the Planing Dinghy that went for many pages. Just searched for it without success.

https://waitematawoodys.files.wordpress.com/2015/10/patiki-kahurangi.jpg
By the stern down trim I would suggest that she is a semi displacement hull form, over driven rather than designed as a planing hull form.

moTthediesel
08-18-2018, 06:24 AM
I would not bank on it. The stresses that the different hulls are exposed to bare no comparison. Shells have a very different framing regime and may well have been skinned differently.

Oh, I take your point, but I was thinking more along the lines of the technical ability to produce, fit, and fasten wooden boat framing and planking of such delicate dimensions. Beside simply maintaining their shape and keeping the water out, those planing dingy hulls would also have to be designed to maintain rig tension as well. That’s a trick the racing shell builders would not have had to deal with. Even Rushton would be into new territory there, as his sailing canoe rigs were (I think) all self-standing.

Tom

Paul Pless
08-18-2018, 06:31 AM
http://forum.woodenboat.com/showthread.php?163530-History-of-the-planing-dinghy

Peerie Maa
08-18-2018, 06:33 AM
Oh, I take your point, but I was thinking more along the lines of the technical ability to produce, fit, and fasten wooden boat framing and planking of such delicate dimensions.

Tom

They have been doing that with sawn framed Thames skiffs for centuries.
https://www.epoxycraft.com/wp-content/uploads/2017/08/Thames-Skiff-29.jpg

Eversince they could make good quality saw plates to convert the wood.

Chip-skiff
08-18-2018, 01:51 PM
http://forum.woodenboat.com/showthread.php?163530-History-of-the-planing-dinghy

Thanks. I think that thread refers to the earlier one I remember. Just searched again with no success.

Here's a photo of Patiki (flatfish) yachts in the Ahuriri Lagoon at Napier NZ, c. 1931.

https://waitematawoodys.files.wordpress.com/2015/10/patiki-yachts-31st-january-1931-mahaurangi-maroondah-swallow1.jpg?w=580&h=338

Do those look like semi-displacement hulls?

Here's another shot of the Kahurangi:

https://waitematawoodys.files.wordpress.com/2015/10/patiki-kahurangi-30s.jpg?w=580&h=773

My recollection is that the planing-hull craft originated with yacht clubs in Auckland by the 1890s, racing on the Waitemata and Manukau Harbours. The Ahuriri Lagoon at Napier was found to be perfect for the planing hulls and huge rigs, and much of the racing enthusiasm migrated accordingly. The 1931 earthquake breached the lagoon and profoundly changed that stretch of coastline.

Peerie Maa
08-18-2018, 02:39 PM
Thanks. I think that thread refers to the earlier one I remember. Just searched again with no success.

Here's a photo of Patiki (flatfish) yachts in the Ahuriri Lagoon at Napier NZ, c. 1931.

https://waitematawoodys.files.wordpress.com/2015/10/patiki-yachts-31st-january-1931-mahaurangi-maroondah-swallow1.jpg?w=580&h=338

Do those look like semi-displacement hulls?

Too much rocker and the buttocks are not straight enough for a planing hull. They are more skimming dish form than anything else. Push a skimming dish hard and it will squat and become semi planing if it has enough reserve buoyancy aft.

Andrew Craig-Bennett
08-18-2018, 03:26 PM
I agree with Nick.

To me, the important point about Fox is that he had served his apprenticeship at a firm - S. E. Saunders, later Saunders-Roe, who built flying boats and very fast (world record breaking) powerboats. This gave him
the knowledge of construction and the understanding of planing hull form.

johnw
08-18-2018, 04:07 PM
Too much rocker and the buttocks are not straight enough for a planing hull. They are more skimming dish form than anything else. Push a skimming dish hard and it will squat and become semi planing if it has enough reserve buoyancy aft.
Designers used to think boats planned on their sterns, but this does not always seem to be the case. Consider the Oz Goose:


https://www.storerboatplans.com/boat/sailing-boat/oz-goose-an-inexpensive-family-sailboat-or-club-training-and-racing-boat/
How does a square Oz Racer/PD Goose sail?The Oz Goose looks odd – so how do they sail? Top recorded speed solo sailing has crept up in the last two years. Originally 12 knots it was raised to 12.9 (both on a tideless lake in Central Texas. And finally raised to 13.8 knots on a tideless lake in the Philippines. Here is the designer’s boat in upwind mode in about 15 knots of wind.
https://storerboats-2pcvbeepenn1.netdna-ssl.com/wp/wp-content/uploads/2016/11/Goose-TLYC-mik-facebook-mod-2-560x420.jpg


This shouldn't be too much of a surprise, as the American scows and the New Zealand patikis were planing before the end of the 19th century. Michael Storer, by the way, has some eccentric theories about planing, because the fact that his Oz Goose design planes goes against what he was taught, and he's trying to explain it.

Or maybe it's not planing, it's just an overdriven hull going at the speed that defines planing. I know we had an interesting discussion about how to define planing on that old thread.

Peerie Maa
08-18-2018, 04:22 PM
^ Racing catamarans are not planing forms, but they can really shuffle along.
Designers who thought boats plane on their sterns were misguided, They plane on the area at and aft of the stagnation point, which is usually under the LcG for the boat to retain trim.

johnw
08-18-2018, 04:30 PM
In any case, the question of whether New Zealand produced planing boats prior to Avenger is not dependent on the patikis.

https://lh5.googleusercontent.com/-eLtFlm7GjvA/UZ262Qfa6_I/AAAAAAAADuc/9jQA8t9hShY/w890-h503-no/New+Zealand+X+Class+5-22-2013+11-35-58+PM.jpg

johnw
08-18-2018, 04:35 PM
^ Racing catamarans are not planing forms, but they can really shuffle along.
Designers who thought boats plane on their sterns were misguided, They plane on the area at and aft of the stagnation point, which is usually under the LcG for the boat to retain trim.
That's why, the first time I saw a Firefly, I thought I was looking at a displacement hull. There was so much V at the stagnation point, compared to American planing classes of the same era, it didn't look like it would generate much lift. It did have some oak rubbing strakes on the bottom, I suppose those helped.

Peerie Maa
08-18-2018, 04:38 PM
In any case, the question of whether New Zealand produced planing boats prior to Avenger is not dependent on the patikis.

https://lh5.googleusercontent.com/-eLtFlm7GjvA/UZ262Qfa6_I/AAAAAAAADuc/9jQA8t9hShY/w890-h503-no/New+Zealand+X+Class+5-22-2013+11-35-58+PM.jpg

Avenger would have been faster power for power when flat out
https://sailcraftblog.files.wordpress.com/2016/10/avenger-lines-1.png?w=701&h=467

Her run is straighter, so she would have unstuck and flown easier.

johnw
08-18-2018, 04:48 PM
Avenger would have been faster power for power when flat out
https://sailcraftblog.files.wordpress.com/2016/10/avenger-lines-1.png?w=701&h=467

Her run is straighter, so she would have unstuck and flown easier.
I did say she was revolutionary.

Peerie Maa
08-18-2018, 05:07 PM
That's why, the first time I saw a Firefly, I thought I was looking at a displacement hull. There was so much V at the stagnation point, compared to American planing classes of the same era, it didn't look like it would generate much lift. It did have some oak rubbing strakes on the bottom, I suppose those helped.

Ray Hunt and Don Levi's deep vee hull forms were certainly planing forms. Deadrise makes for a softer ride in waves, the shape of the buttocks makes a planing form.

http://img.boatmaginternational.com/2018/01/Levi-Corsair_6.jpg

http://img.boatmaginternational.com/2018/01/Levi-Corsair_3-938x535.jpg


There was so much V at the stagnation point, compared to American planing classes of the same era May be your water is flatter than the sea water we race on. The flatter hull forms with lower chines at the bow common on US motor boats compared to ours would suggest that to be the case,

johnw
08-18-2018, 05:09 PM
Ray Hunt and Don Levi's deep vee hull forms were certainly planing forms. Deadrise makes for a softer ride in waves, the shape of the buttocks makes a planing form.

http://img.boatmaginternational.com/2018/01/Levi-Corsair_6.jpg

http://img.boatmaginternational.com/2018/01/Levi-Corsair_3-938x535.jpg
And the strakes are important for making them plane, which is why I thought of that in connection with the Firefly.

Peerie Maa
08-18-2018, 05:20 PM
And the strakes are important for making them plane, which is why I thought of that in connection with the Firefly.

No, the strakes reduce wetter surface area by shedding the film of attached water, hence friction, which reduces the power required by a small factor. They have little effect on generating the lift force as the water that they shed is no longer a part of the body of water supporting the weight of the hull.

johnw
08-18-2018, 05:42 PM
No, the strakes reduce wetter surface area by shedding the film of attached water, hence friction, which reduces the power required by a small factor. They have little effect on generating the lift force as the water that they shed is no longer a part of the body of water supporting the weight of the hull.
Your disagreement is with Hunt. From the Hunt Design website:


A high chine forward and multiple spray strips knock down spray, prevent water from climbing the topsides, add lift and reduce wetted surface. Less wetted surface means reduced resistance, greater speed and increased economy. A widely flared forward topsides encloses substantial buoyancy that reduces the potential for burying the bow or taking "solid" water over it.

The strakes do work as you say, but they also add lift, according to Hunt.

Peerie Maa
08-19-2018, 03:13 AM
Your disagreement is with Hunt. From the Hunt Design website:


The strakes do work as you say, but they also add lift, according to Hunt.

A minescule amount in the scheme of things. If you consider the immersed area of the rails, it is the same area as the bottom that they cover, so the only difference is that those immersed rails have no dead rise. The added lift is a second order effect and of secondary importance. He is not telling porkys, but he is exaggerating a tad.
This
and reduce wetted surface. Less wetted surface means reduced resistance, greater speed and increased economy.is the key statement.

johnw
08-19-2018, 01:35 PM
A minescule amount in the scheme of things. If you consider the immersed area of the rails, it is the same area as the bottom that they cover, so the only difference is that those immersed rails have no dead rise. The added lift is a second order effect and of secondary importance. He is not telling porkys, but he is exaggerating a tad.
Thisis the key statement.
The stakes are entirely immersed when the boat is stopped, so I would assume they help the boat get up on a plane. In any case, I think we agree that they both provide some lift and make the boat shed water to reduce wetted surface.