Technical Talk

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quicksilver-wsr
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Re: Technical Talk

Post by quicksilver-wsr » Thu May 14, 2015 9:48 am

True enough - eventually the tech matures and becomes useful.

I nearly posted on the space thread on here a few months back, because the crew on the ISS needed some oddball bit of kit they didn't have, so someone on the ground designed the part and beamed the CNC programme up to orbit, whereupon the ISS crew simply printed the part with their on-board 3D printer!

Some of the stuff that's coming off these things these days is proper real-world product. It's now quite feasible, for example, to do low-volume production runs with them and not bother with expensive tooling and manufacturing processes.

A tool that started off for prototyping is fast becoming a viable, economical tool for manufacturing.

Nigel

Gareth Hayes
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Re: Technical Talk

Post by Gareth Hayes » Thu Jul 23, 2015 9:11 pm

You've probably already answered this question somewhere, so please forgive my "level 3 idiot" ignorance. But how did you get K7 back in one piece? All those years she was stuck at the bottom of lake Coniston, much like RMS Titanic the big blue boat was in half. So what did you do once you'd got the two halves in decent shape again, weld them together, or somethin a little more complicated?

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Richie
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Re: Technical Talk

Post by Richie » Sat Jul 25, 2015 4:43 pm

Best way to answer that would be to go back to the beginning of the diary page and have a look see.
Clarence come out ov zat tank at vonz !

Daz27
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Re: Technical Talk

Post by Daz27 » Tue Jul 28, 2015 11:05 am

Richie wrote:Best way to answer that would be to go back to the beginning of the diary page and have a look see.
Watch out though, you'll quickly become addicted and be sitting at your computer every night like I do, jonesing and needing a diary hit... :D

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Renegadenemo
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Re: Technical Talk

Post by Renegadenemo » Thu Jul 30, 2015 2:29 am

Do you want it now or do you want it right?

https://vimeo.com/118564546
I'm only a plumber from Cannock...

"As to reward, my profession is its own reward;" Sherlock Holmes.

'Sometimes you gotta be an S.O.B if you wanna make a dream reality' Mark Knopfler

Daz27
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Re: Technical Talk

Post by Daz27 » Thu Jul 30, 2015 11:28 am

Renegadenemo wrote:Do you want it now or do you want it right?

https://vimeo.com/118564546
I want it right, kind Sir. Thankfully there is so much material in the older entries that I find the itch is mostly scratched by revisiting them. :)

dave
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Re: Technical Talk

Post by dave » Fri Jul 31, 2015 4:14 pm

In its final configuration. Campbell had steering difficulty with K7, as it had a bias to go to port (steer towards the left). This condition resulted in a number of investigations, removal of the centrally mounted water brake and re fitting of the transom fin into it's original position. All of which appeared not to alleviate the condition. So the water brake and fin were reassigned to their respective locations.
Noting the bird strike damage on the port fairing that to must have caused a significant increase in drag, contributing to a "Port Bias"

Before final lift off. K7 was travelling at a speed less than it's peak velocity of 328 mph. some 5 degrees off track. So why did it take off as he was also entering smoother water as well?

K7 was a three pointer hydroplane. With two planing surfaces, one on each sponson and the third mounted at the rear transom.
To correct the Port Bias (Being 5 degrees off course). Campbell would have to input considerable correcting force. In doing so would result in an increase in load on the port surface and a corresponding reduction in downward force on the starboard plane. This condition we have all experienced when driving a fast car and initiating a turn. The centrifugal force causes the vehicle to lean outwards and that is not at 300 mph.
K7 would naturally want to roll about it's stability triangle formed by Port sponson and rear transom surfaces. Thus creating a significant window for air to rush under, the rest being history.

It should be noted that a similar lifting condition was observed during the North - South run.

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Renegadenemo
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Re: Technical Talk

Post by Renegadenemo » Fri Jul 31, 2015 4:35 pm

They need have looked no further than the half a ton of extra gubbins bolted into the left side of the boat in the re-engining exercise for their steering troubles and a right steering input would cause the front to lift due to gyrosocipic precession so it's no great surprise it took off, especially without engine thrust.
I'm only a plumber from Cannock...

"As to reward, my profession is its own reward;" Sherlock Holmes.

'Sometimes you gotta be an S.O.B if you wanna make a dream reality' Mark Knopfler

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Mike Bull
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Re: Technical Talk

Post by Mike Bull » Fri Jul 31, 2015 4:48 pm

dave wrote:In its final configuration. Campbell had steering difficulty with K7, as it had a bias to go to port (steer towards the left). This condition resulted in a number of investigations, removal of the centrally mounted water brake and re fitting of the transom fin into it's original position. All of which appeared not to alleviate the condition. So the water brake and fin were reassigned to their respective locations.
Noting the bird strike damage on the port fairing that to must have caused a significant increase in drag, contributing to a "Port Bias"
Firstly, I would say 'name your source' re the steering being biased to the left- there's certainly mention (Neil's book, for one) that the steering felt 'unusual', and runs were made on the morning of the 10th December with the brake removed and the stabilising fin back in the centre of the transom, but nothing came of this and by that same afternoon everything was restored to it's usual position. Are we to believe that Campbell kept working the boat to ever faster speeds, still with errant steering?!

And re the duck dent- this occurred on the 27th and the boat didn't run again until the 4th- and we never had any feedback after that morning. So, who's to say exactly what (if any) appreciable effect the dent had?

f1steveuk
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Re: Technical Talk

Post by f1steveuk » Sat Aug 01, 2015 11:36 am

I think both Ken and Leo said any effect created by the bird strike would have been "negligable". Ken did once mention the possibilty of a torque reaction with the rotation of the engine effected the steering, but I'm sure the Orph' and the Beryl span the same way, and I can't think there would have been a huge increase in this effect?
Steve Holter, UK and France, and sometimes reality....................

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