Author Topic: Edwards 5 Cylinders.  (Read 3795 times)

Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #60 on: March 15, 2019, 11:25:24 PM »
Nice  :)

I tend to think of the master-rod as the one straight up = cylinder no 1 .... not that it matters  ;)
Oups!! ;-)

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Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #61 on: March 21, 2019, 11:36:16 AM »
Test.

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Offline Vixen

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Re: Edwards 5 Cylinders.
« Reply #62 on: March 21, 2019, 04:22:15 PM »
Nice  :)

I tend to think of the master-rod as the one straight up = cylinder no 1 .... not that it matters  ;)

It was actually common practice for the master rod to be located in one of the two lower cylinders. The master rod does it's own share of the work plus a small percentage of sideload from each of the other slave rods. The lower cylinders are olier (due to gravity) than the upper cylinders, therefore were considered the best place to locate the higher loaded master rod and piston.

By some forgotten drawing convention, it was also normal for the Master Rod to be drawn in 'Number One' cylinder even though it practice it could be located in one of the two lower cylinders.

Mike
It is the journey that matters, not the destination

Online Admiral_dk

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Re: Edwards 5 Cylinders.
« Reply #63 on: March 21, 2019, 05:05:21 PM »
Quote
By some forgotten drawing convention, it was also normal for the Master Rod to be drawn in 'Number One' cylinder even though it practice it could be located in one of the two lower cylinders.

Well that explains a lot. With that said - I have seen quite a number of sawn-through engines @ a number of museums and not one of them had shown the master-rod in any other direction than up …. but if the drawings are shown as you say - I would show the engine the same way - unless the rest of the plane / mounting hardware indicates differently.

Offline Vixen

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Re: Edwards 5 Cylinders.
« Reply #64 on: March 21, 2019, 07:05:39 PM »
The designer and  the engine builder are free to place the master rod in whichever cylinder they chose. It really does not matter, the engine will run correctly.

Bristol's chose to take advantage of the oilier environment in the lower cylinders, other designers do not

Chapter 23 ; 'Engine Erection Procedure' of my Bristol Mercury MK VIII works manual states that when fitting the crankshaft assembly into the rear crankcase half "Position the articulated rods in line with their respective cylinder half apertures; the master rod being aligned with the No 6 aperture.

Chapter 20; 'Assembling the Engine' of my Bristol Jupiter Mk VIII works manual similarly states " The master rod is situated in No 6 aperture"

So that's how I built my 1/4 scale Bristol Mercury and My 1/3 scale Bristol Jupiter engines.

In both cases the drawings in the manuals show the master rod in no 1 cylinder. Go figure that out !!!!!!!!!!!!

Other engine builders may do it differently, it's your choice.

Mike
It is the journey that matters, not the destination

Online Admiral_dk

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Re: Edwards 5 Cylinders.
« Reply #65 on: March 21, 2019, 09:30:21 PM »
Mike - I'm not questioning your statement, and the oiling issue makes perfect sense .... it's more that I find it a bit amusing, that the drawing convention makes many (like myself) think that the master-rod always is number one and always up ....  :-[

Thank you for the "heads up" and sorry glorfindel  :-[ ;D