Author Topic: By Jupiter  (Read 75307 times)

Offline muddled engineer

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Re: By Jupiter
« Reply #330 on: May 31, 2019, 05:18:50 PM »
Hi Mike and all,

I am not sure if  can bring any of my enines down to Guildford as I have no transport any more, but I will
be there if I can walk. or get the bus.

Eric :old:

Offline Vixen

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Re: By Jupiter
« Reply #331 on: May 31, 2019, 05:25:28 PM »
Hello Eric :old:

You live only a few miles from the show ground. I would be happy to collect you and your engines each morning and return you home in the evening. Not a problem

Cheers

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline muddled engineer

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Re: By Jupiter
« Reply #332 on: May 31, 2019, 07:58:10 PM »
Hi Mike,
Thanks a lot Mike, let me know  what time you want me ready.

Eric :old:

Offline Admiral_dk

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Re: By Jupiter
« Reply #333 on: May 31, 2019, 08:52:40 PM »
Quote
how do you stop the test bench from flying away?
    :lolb:   :lolb:  sorry, but I got a good laugh out of this one ....

On another note (almost literately) ; It became a very bad day in the first half of the nineties when it was announced that the last Honduras Mahogany tree had been cut down => no more of one of the absolutely best woods for guitar building was no more  :'(

I talked a few month ago with one off the best custom guitar builders here in Denmark and when I mentioned this, he say that this was not the case anymore ...  :headscratch: ...
It turns out that there where a lot off saplings in many of the stripped woods in Honduras and these where left where they stood => there are now a good amount off young trees => if left alone, this species will have a fine chance of recovery  :whoohoo: (though I will not have any in my time).

Offline Vixen

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Re: By Jupiter
« Reply #334 on: May 31, 2019, 09:10:08 PM »
Hello Per,

That's correct, in addition to propellers, Honduras mahogany was also the material of choice for the finest hand crafted guitars. It was used both for the neck and also for the sides of the sound box, It gave a deeper, richer, more mellow sound (voice) to the guitar than any alternative wood. So it's good news that the Honduras forests are slowly recovering, but as you say, not in our time.

Quote
how do you stop the test bench from flying away?
   
Reduce the pitch and lower the note :lolb: :lolb: Works for propellers and gutars.

Mike

« Last Edit: May 31, 2019, 09:29:23 PM by Vixen »
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Art K

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Re: By Jupiter
« Reply #335 on: June 01, 2019, 04:39:11 AM »
Mike,
There was an article in a recent Smithsonian Air & Space magazine about a gal who learned from her grandfather how to make propellers and when he passed took over the business. Now you have the opportunity to work with the brown stuff, enjoy.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Vixen

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Re: By Jupiter
« Reply #336 on: June 01, 2019, 09:28:51 AM »
Hello Art,

I have heard about this young lady. She hand crafts the blades in the traditional way, none of this CNC router rubbish. Blonde and attractive as well.

Mike  :old:
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline dieselpilot

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Re: By Jupiter
« Reply #337 on: June 01, 2019, 12:42:12 PM »
http://www.culverprops.com

How fast do you intend to run the engine? That prop won't hold it back to 2000RPM.

Offline Vixen

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Re: By Jupiter
« Reply #338 on: June 01, 2019, 12:51:21 PM »
The Jupiter engine revs to about 2,400 RPM. however the reduction gear reduces the prop speed to about 1,200 RPM. Nice and  slow 'n' cool

The Culver prop calculator says a 40" diameter x 28" pitch prop turning at 1,200 RPM should give a wind (air) speed of 32 MPH and a tip speed of 210 Ft/sec.

That's what I chose for bench running the Jupiter

Mike 8) 8) 8)

« Last Edit: June 01, 2019, 01:20:17 PM by Vixen »
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Jo

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Re: By Jupiter
« Reply #339 on: June 01, 2019, 03:10:32 PM »
Don't get your thumb in front of it Mike  :paranoia:

Jo
Enjoyment is more important than achievement.

Offline Ian S C

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Re: By Jupiter
« Reply #340 on: June 01, 2019, 03:16:36 PM »
I worked on aero engine overhaul back in the 1960s, and for test running our engines, mainly 260hp IO-470 Continental we had a coarse pitched prop with shortened blades, this prop was calibrated to absorb the required power at the correct rpm. For other engines we had an adjustable pitch prop.
Ian S C

Offline Vixen

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Re: By Jupiter
« Reply #341 on: June 01, 2019, 03:30:18 PM »
Don't get your thumb in front of it Mike  :paranoia:

Jo

Ha ha, point noted. Radial engines are quite benign engines to hand start by swinging the prop, unlike that wicked Fellgiebel single cylinder that bit poor Eric so badly.

To be on the safe side, I will be plugging an electric starter into the rear of the engine

Mike :zap: :zap:
« Last Edit: June 01, 2019, 05:08:57 PM by Vixen »
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Vixen

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Re: By Jupiter
« Reply #342 on: June 01, 2019, 03:41:06 PM »
I worked on aero engine overhaul back in the 1960s, and for test running our engines, mainly 260hp IO-470 Continental we had a coarse pitched prop with shortened blades, this prop was calibrated to absorb the required power at the correct rpm. For other engines we had an adjustable pitch prop.
Ian S C

Hello Ian,
I had hoped to call in and see you earlier this year, but my month in NZ South Island was canceled at the last moment.

Yes, I could use a course pitch club propeller if I wished to run the Jupiter at full power at the correct RPM. Instead, I chose a full diameter propeller with fine pitch which would not unduly load the engine and would not produce an excess of thrust and windage. Even so, the test stand will need to be well tethered to the ground. I have no plans or intentions to fly the Jupiter

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Vixen

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Re: By Jupiter
« Reply #343 on: June 03, 2019, 02:25:05 PM »
Hey Rolf, can you see what it's going to be, yet?





All we need now is some glue

Stay tuned

Mike
« Last Edit: June 03, 2019, 04:08:07 PM by Vixen »
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline crueby

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Re: By Jupiter
« Reply #344 on: June 03, 2019, 04:57:56 PM »
Oh, a vertical takeoff lawn mower!
 :slap:
Oh.

 

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