De Haviland Mosquitoes.

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Kittyhawk

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A couple of Mosquitoes at 1:40 scale.
The model in the foreground in our beautiful native Rimu, the other in our despicable native Kauri. But I take no responsibility for it, it's what the customer wanted and he supplied his own timber.
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Wonderful. Mossie is a favourite warbird but I have never seen one in the flesh. I could stare at one of those all day.

Pete
Not far from us is Ardmore aerodrome which is also the home of the NZ Warbirds association. They also do a lot of rebuilding of vintage aircraft and have spent years getting a mosquito airworthy and it recently made it maiden(?) flight and it's flight path was right over our house. A mossie at low altitude and the roar of a couple of Merlins is something I'll never forget.
And here's a tricky question relating to my wooden models. The Merlin is a V12 so why are there only five exhaust extractors each side of the engine?
 
Some had 5 stacks and some 6. I searched De Havilland Mosquito engines and then looked at the images. One said "odd number of exhaust stacks..." I clicked it and it said the 5th and 6th stacks were combined to (A) keep the hot exhaust from the leading edge of the wood wing or (B) to keep the hot exhaust gasses from the radiator intakes. It was cooled a little more before getting into the intake. I think the designers thought they would screw with us 80 odd years into the future. "Hey Neville. Let's combine the 5th and 6th exhaust pipes into one. They will never figure out why! 🤣🤣🤣

Pete
 
Excellent! Thank you, that makes perfect sense.
Aircraft design is fascinating. Another puzzling thing is why the engine nacelles were carried back beyond the trailing edge of the wing, especially as the undercarriage retracted into it well forward of this. So I discovered courtesy of Mr. Google that a truncated nacelle caused disturbed air over the tailplane with a resulting loss of efficiency - extending them to a point resolved the problem. Interesting, and I wish I knew more about aerodynamics.
 
Fab! But why is Kauri despicable?
Kauri is a NZ icon.
The tree is magnificent, 60 metres high with a girth of 15 metres and a lifespan of 2000years. The few remaining are protected. Maori used it as well as Totara for their canoes and rumour has it that Nelson's Victory had Kauri topmasts in the battle of Trafalgar. In the early 1800's the Pioneer settlers felled a huge amount for buildings and a large shipbuilding industry, vital to the colony for transportation as our mountainous topography made road building incredibly difficult.
So the timber has assumed an almost mythical status. What seems to have been forgotten amongst all the hullabaloo about the timber is that only the heart was used - the sapwood was discarded.
By the time the 1960's and 70's came along and I started building a couple of yachts the timber was scarce and the sapwood was about all you could get. But to my generation that grew up with all the hype surrounding the timber Kauri, even the sap, had gone from being the best boatbuilding timber in NZ to the best boatbuilding timber in the world and quite probably in the entire universe. To say out loud that you didn't like Kauri would result in a stunned silence from your shocked and disbelieving audience.
I'm telling you this to give an idea as to the reverential awe in which the timber is held in NZ.
The man who commissioned the Kauri Mosquito is 74 years old. His father owned a saw mill and he had kept the few pieces since his boyhood. He bought them to me wrapped up in a blanket together with instructions on its storage until I would start on his model. Out of direct sunlight, not too much humidity, not too hot etc etc. And I had to recite three Hail Mary's before cutting into it. Alright, not really but you get the idea.
From my side of the transaction it was oh buggar, blooming Kauri......
The timber he gave me was sap.
First of all, the stuff is soft. Normal handling will mark it and it's very porous. My wife doesn't think much of my workshop practices so when I come for yet another bandaid she tends to repeat her favorite mantra 'in every job a little blood must flow', and blood is almost impossible to get out of Kauri. The timber has a tendency to split along the grain line - whack a nail into it without pre drilling and like as not it will not split there but on the closest grain line. It is frustrating to turn up a propellor spinner and then find some hours later that the work has split due to the stresses of being on the lathe. The timber is unstable. Cut and dress up a plank and leave in on the bench. Next day there's a good chance it will be either cupped or bowed or twisted, maybe all three. I normally finish my models with 240grit prior to oiling but Kauri requires 400 grit and care is needed to ensure the paper is absolutely clean. Any contaminant will score or stain the wood. And from my boatbuilding experience the timber is prone to rot and wood borer think it's a pretty tasty snack. And to cap it all off, Kauri is bland, bland, bland.
So I'm sorry, I've gone on a bit here but I'm very disappointed in the kauri mosquito, firstly on behalf of the customer who entrusted me with his treasured piece of crappy timber and secondly for my own sake because maybe my dislike of the wood prevented me from giving it my best.
 
Just wish we had the option of different hard woods here.....
There is some Oak trees here but never seen any timber.....
I like Olive but there's no planks.....!!!!!
even bigger bits to make a one peice breadboard are diff to find....

out of interest, knarley old Olive trees tend to die and rot in the center...but still give excellent oil quantities....
our oldest tree is rather like that and must be over 500 years old, roughly 1m in diameter.....
we got 27 liters of oil from our few olive trees.......nice to think it's ours when using it on a salad.....
 
Kauri is a NZ icon.
The tree is magnificent, 60 metres high with a girth of 15 metres and a lifespan of 2000years. The few remaining are protected. Maori used it as well as Totara for their canoes and rumour has it that Nelson's Victory had Kauri topmasts in the battle of Trafalgar. In the early 1800's the Pioneer settlers felled a huge amount for buildings and a large shipbuilding industry, vital to the colony for transportation as our mountainous topography made road building incredibly difficult.
So the timber has assumed an almost mythical status. What seems to have been forgotten amongst all the hullabaloo about the timber is that only the heart was used - the sapwood was discarded.
By the time the 1960's and 70's came along and I started building a couple of yachts the timber was scarce and the sapwood was about all you could get. But to my generation that grew up with all the hype surrounding the timber Kauri, even the sap, had gone from being the best boatbuilding timber in NZ to the best boatbuilding timber in the world and quite probably in the entire universe. To say out loud that you didn't like Kauri would result in a stunned silence from your shocked and disbelieving audience.
I'm telling you this to give an idea as to the reverential awe in which the timber is held in NZ.
The man who commissioned the Kauri Mosquito is 74 years old. His father owned a saw mill and he had kept the few pieces since his boyhood. He bought them to me wrapped up in a blanket together with instructions on its storage until I would start on his model. Out of direct sunlight, not too much humidity, not too hot etc etc. And I had to recite three Hail Mary's before cutting into it. Alright, not really but you get the idea.
From my side of the transaction it was oh buggar, blooming Kauri......
The timber he gave me was sap.
First of all, the stuff is soft. Normal handling will mark it and it's very porous. My wife doesn't think much of my workshop practices so when I come for yet another bandaid she tends to repeat her favorite mantra 'in every job a little blood must flow', and blood is almost impossible to get out of Kauri. The timber has a tendency to split along the grain line - whack a nail into it without pre drilling and like as not it will not split there but on the closest grain line. It is frustrating to turn up a propellor spinner and then find some hours later that the work has split due to the stresses of being on the lathe. The timber is unstable. Cut and dress up a plank and leave in on the bench. Next day there's a good chance it will be either cupped or bowed or twisted, maybe all three. I normally finish my models with 240grit prior to oiling but Kauri requires 400 grit and care is needed to ensure the paper is absolutely clean. Any contaminant will score or stain the wood. And from my boatbuilding experience the timber is prone to rot and wood borer think it's a pretty tasty snack. And to cap it all off, Kauri is bland, bland, bland.
So I'm sorry, I've gone on a bit here but I'm very disappointed in the kauri mosquito, firstly on behalf of the customer who entrusted me with his treasured piece of crappy timber and secondly for my own sake because maybe my dislike of the wood prevented me from giving it my best.
Great answer! I Asked ask I spent a month in NZ in 2005 with friends in Auckland, and spent a memorable few days hiking in and around the Kauri Forests. From which I took the understanding of the reverence that these trees hold. I was also in awe of them in the flesh, so to say. Hence my question. I loved the answer, both the emotive, and the practical. Additionally I also came home with a bowl made from swamp Kauri, which is one of my prize possessions. A wood that is far from soft and dull.

Fitz
 
Kauri is a NZ icon.
The tree is magnificent, 60 metres high with a girth of 15 metres and a lifespan of 2000years. The few remaining are protected. Maori used it as well as Totara for their canoes and rumour has it that Nelson's Victory had Kauri topmasts in the battle of Trafalgar. In the early 1800's the Pioneer settlers felled a huge amount for buildings and a large shipbuilding industry, vital to the colony for transportation as our mountainous topography made road building incredibly difficult.
So the timber has assumed an almost mythical status. What seems to have been forgotten amongst all the hullabaloo about the timber is that only the heart was used - the sapwood was discarded.
By the time the 1960's and 70's came along and I started building a couple of yachts the timber was scarce and the sapwood was about all you could get. But to my generation that grew up with all the hype surrounding the timber Kauri, even the sap, had gone from being the best boatbuilding timber in NZ to the best boatbuilding timber in the world and quite probably in the entire universe. To say out loud that you didn't like Kauri would result in a stunned silence from your shocked and disbelieving audience.
I'm telling you this to give an idea as to the reverential awe in which the timber is held in NZ.
The man who commissioned the Kauri Mosquito is 74 years old. His father owned a saw mill and he had kept the few pieces since his boyhood. He bought them to me wrapped up in a blanket together with instructions on its storage until I would start on his model. Out of direct sunlight, not too much humidity, not too hot etc etc. And I had to recite three Hail Mary's before cutting into it. Alright, not really but you get the idea.
From my side of the transaction it was oh buggar, blooming Kauri......
The timber he gave me was sap.
First of all, the stuff is soft. Normal handling will mark it and it's very porous. My wife doesn't think much of my workshop practices so when I come for yet another bandaid she tends to repeat her favorite mantra 'in every job a little blood must flow', and blood is almost impossible to get out of Kauri. The timber has a tendency to split along the grain line - whack a nail into it without pre drilling and like as not it will not split there but on the closest grain line. It is frustrating to turn up a propellor spinner and then find some hours later that the work has split due to the stresses of being on the lathe. The timber is unstable. Cut and dress up a plank and leave in on the bench. Next day there's a good chance it will be either cupped or bowed or twisted, maybe all three. I normally finish my models with 240grit prior to oiling but Kauri requires 400 grit and care is needed to ensure the paper is absolutely clean. Any contaminant will score or stain the wood. And from my boatbuilding experience the timber is prone to rot and wood borer think it's a pretty tasty snack. And to cap it all off, Kauri is bland, bland, bland.
So I'm sorry, I've gone on a bit here but I'm very disappointed in the kauri mosquito, firstly on behalf of the customer who entrusted me with his treasured piece of crappy timber and secondly for my own sake because maybe my dislike of the wood prevented me from giving it my best.
You obviously work with this wood and know what you are talking about, I'd been told kauri was very rot and worm resistant, do you know if that's true of the hart wood?

As everybody is saying the models are beautiful, and the mossie a truly remarkable aircraft
 
I too love your rendition of all of the aircraft you have made and especially the Mossie.

It was a great shame that they didn't have the glues that we have today. They were a world beater until the heat and humidity of the far east got to those glues.

When I was stationed in Singapore in the late 60s I spent some time on 81 Sqdn. I was working on Canberra PR7s and missed the Mossies by a few years. They were the last sqdn in the R.A.F. to have them and they were the photo recon version. I would have loved to have spent some time on them!
 
I too love your rendition of all of the aircraft you have made and especially the Mossie.

It was a great shame that they didn't have the glues that we have today. They were a world beater until the heat and humidity of the far east got to those glues.

When I was stationed in Singapore in the late 60s I spent some time on 81 Sqdn. I was working on Canberra PR7s and missed the Mossies by a few years. They were the last sqdn in the R.A.F. to have them and they were the photo recon version. I would have loved to have spent some time on them!
My father was a navigator on Mosquitoes when the squadron moved to Singapore in the early 50s. He loved them ……he was then on Canberras for the remainder of his flying days😊
 
Additionally I also came home with a bowl made from swamp Kauri, which is one of my prize possessions. A wood that is far from soft and dull.
Yes, swamp kauri is something special and having spent 100's of years underground there is no doubting it hardness and rot resistance. Swamp kauri is still dug up now and again and invariably ends up at auction where artists and craftsmen bid truly eye-watering amounts of money to aquire it. I envy you your bowl.
Kauri is an enigmatic timber in that you can never be sure what to expect from it - probably why I don't like it.
Concerning the models you may have noticed that in the pic of the two aeroplanes together the kauri one is to the rear and all the close ups are of the Rimu one. That's because I'm a bit ashamed of it. So here's a closeup of the kauri one.
20210714_112512.jpg

The fuselage and engines are made of sap wood - that's the stuff that's so soft it takes offence just from you looking at it. The wings and tail plane are made of mottled kauri and I don't know exactly what that is. I think its the interface between the sap and the heart. Its the stuff that splits and chips. The propeller blades are from Rimu because try as I might I couldn't do them in kauri.
In the pioneer days NZ had only three exports - gold, kauri timber and kauri gum. The timber gave rise to the story that Nelson's Victory had kauri topmasts and the kauri gum was in high demand for many reasons but the only one I know was that it was used in the manufacture of high grade varnishes. Gum digging was the province of the Dalmation immigrants of which there were many thousands. Tools of the trade were a spade and a long metal rod with which they probed the ground where ancient forests once stood and then dug when the rod hit something. The transient gum diggers were so synonymous with NZ's early colonial history that the word has entered into the vernacular. Got a bad tooth? You don't make an appointment with the dentist - you go to see the gum digger.
I'd been told kauri was very rot and worm resistant, do you know if that's true of the hart wood?
In the early 70's the child bride and I bought an acre of rural land and it had a very dilapidated tiny gum diggers cottage on it, built of kauri. I got a building inspector to give an opinion as to whether or not it could be saved. And his opinion was it was only all the woodworm holding hands that was preventing it from falling down. So the timber is prone to infestation.
Concerning rot I have no first hand experience but as a boy I used to haunt all the local boat builders and I can still smell the kerosene. It was mixed with copper naphtenate and lathered all over the kauri boats under construction. This was a rot preventative and the smell lasted on board for years so I suppose sap kauri was prone to rot if untreated. Heart, though was durable and there is a small fleet of 'A' class yachts still racing today, well over a hundred and twenty years after their launch date. Heart and sap, good and bad,
Sorry, I've rambled on again - never ask and old man a question...
 
Yes, swamp kauri is something special and having spent 100's of years underground there is no doubting it hardness and rot resistance. Swamp kauri is still dug up now and again and invariably ends up at auction where artists and craftsmen bid truly eye-watering amounts of money to aquire it. I envy you your bowl.
Kauri is an enigmatic timber in that you can never be sure what to expect from it - probably why I don't like it.
Concerning the models you may have noticed that in the pic of the two aeroplanes together the kauri one is to the rear and all the close ups are of the Rimu one. That's because I'm a bit ashamed of it. So here's a closeup of the kauri one.
View attachment 113997
The fuselage and engines are made of sap wood - that's the stuff that's so soft it takes offence just from you looking at it. The wings and tail plane are made of mottled kauri and I don't know exactly what that is. I think its the interface between the sap and the heart. Its the stuff that splits and chips. The propeller blades are from Rimu because try as I might I couldn't do them in kauri.
In the pioneer days NZ had only three exports - gold, kauri timber and kauri gum. The timber gave rise to the story that Nelson's Victory had kauri topmasts and the kauri gum was in high demand for many reasons but the only one I know was that it was used in the manufacture of high grade varnishes. Gum digging was the province of the Dalmation immigrants of which there were many thousands. Tools of the trade were a spade and a long metal rod with which they probed the ground where ancient forests once stood and then dug when the rod hit something. The transient gum diggers were so synonymous with NZ's early colonial history that the word has entered into the vernacular. Got a bad tooth? You don't make an appointment with the dentist - you go to see the gum digger.

In the early 70's the child bride and I bought an acre of rural land and it had a very dilapidated tiny gum diggers cottage on it, built of kauri. I got a building inspector to give an opinion as to whether or not it could be saved. And his opinion was it was only all the woodworm holding hands that was preventing it from falling down. So the timber is prone to infestation.
Concerning rot I have no first hand experience but as a boy I used to haunt all the local boat builders and I can still smell the kerosene. It was mixed with copper naphtenate and lathered all over the kauri boats under construction. This was a rot preventative and the smell lasted on board for years so I suppose sap kauri was prone to rot if untreated. Heart, though was durable and there is a small fleet of 'A' class yachts still racing today, well over a hundred and twenty years after their launch date. Heart and sap, good and bad,
Sorry, I've rambled on again - never ask and old man a question...

Well I for one - and I'm sure there are others here - who find your info absolutely fascinating. Re the Mossie you're "ashamed of", well I must say if that's something to be ashamed of I'm VERY glad you haven't seen some of the "stuff" I've produced (us old blokes must stick together - "she'll be right Trev"!
 
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