Author Topic: By Jupiter  (Read 35639 times)

Offline Roger B

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Re: By Jupiter
« Reply #405 on: July 06, 2019, 05:58:30 PM »
Excellent as ever  :praise2:  :praise2: As a complete aircraft numbskull is the propeller torque transferred by the clamping pressure or by the bolts in shear?  :headscratch:
Best regards

Roger

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Re: By Jupiter
« Reply #406 on: July 06, 2019, 09:53:30 PM »
Hello Roger,

That's correct, A long thin bolt can always transmit a larger load in tension than it can in sheer. The engine torque is transferred by clamping the two steel discs of the propeller hub tightly to the wooden propeller. Theoretically the bolts should not see any sheer loads. The parallel splines on the front steel disc are there to ensure the engine torque is shared equally to both sides of the propeller.

Mike
It is the journey that matters, not the destination

Offline mike mott

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Re: By Jupiter
« Reply #407 on: July 17, 2019, 03:51:36 PM »
Hello Mike'
I have just finished my early morning read, and chose your build today. I am catching up on a few of the builds that cover the broad spectrum of this wonderful forum. All I can say is that it is very inspiring and humbling at the same time. I will be sharing your adventures with casting the manifolds a good friend who is an award winning silversmith. She has a regular group session at her studio on Wednesday mornings for half a dozed folk who are not beginners anymore. There is an area for wax work that I will look at with a different perspective after your journey with the wax.
Not knowing much about working model aero engines I am blown away by the detail and ingenuity that you have shown to replicate this engine,  I read through Dan's blog first before reading your contribution. A great work by both of you, thanks for sharing.

Mike     
If you can imagine it you can build it

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Re: By Jupiter
« Reply #408 on: July 17, 2019, 09:08:25 PM »
Hello Mike,

I have been quietly following your new workshop topic. You have made me quite envious of your 12 month a year, indoor, heated model building workshop. I have to settle for an  outside garage, which is OK for about nine months of the year.

Thanks for your generous words about the Jupiter. Like your Bristol cutter, the larger scale allows a lot more detail to be added. Yes, Dan set the bar very high and I struggle to achieve his standard of workmanship. We are well on the way to completing the engine.

Regards

MIke
It is the journey that matters, not the destination

Online Vixen

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Re: By Jupiter
« Reply #409 on: July 18, 2019, 05:35:07 PM »
Yes, decision made, it's split pins.

In Dad's old tool box, I found a small cardboard box containing one ounce of small split pins. The box was marked AM (Air Ministry) with the Kings Crown and dated 1944. Dad must have "liberated" them way back then. "You never know when these may come in handy". They had to wait 75 years for their time to arrive.

Mike





It seems that way back in 1944 everything was rationed and in short supply, only enough cardboard available to make a very tiny box, which contained 1 gross (144) split pins 1/32" (0.8mm) diameter by 3/8" (9.5mm) long. They are exactly right for the propeller hub bolts.

Mike
It is the journey that matters, not the destination

Offline mike mott

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Re: By Jupiter
« Reply #410 on: July 18, 2019, 06:12:43 PM »
It is great when something finds its time for being used, when it could have so easily have been discarded.

Mike
If you can imagine it you can build it

Offline Ian S C

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Re: By Jupiter
« Reply #411 on: Today at 04:12:17 AM »
Much easier having the split pins like that, last time I needed ones that size I had to make my own, clamped a bit of wire in a fretsaw frame and filed it flat to half thickness, then folded them to split pin shape and cut to lenght, a bit tedious.
Ian S C

Offline Jasonb

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Re: By Jupiter
« Reply #412 on: Today at 07:30:15 AM »
Don't envy the job of cleaning the rust off all of those pins

Online Vixen

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Re: By Jupiter
« Reply #413 on: Today at 08:39:08 AM »
A dip in citric acid pickle would be a whole lot easier than Ian's method of filing down some round wire to a D section

Mike
It is the journey that matters, not the destination