Author Topic: Edwards 5 Cylinders.  (Read 5196 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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Online 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

Offline 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.

Online 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

Offline 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

Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #66 on: April 01, 2019, 02:24:55 PM »
Did those little rocker buttons this morning.

I never did such a small parts.

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Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #67 on: April 03, 2019, 06:22:44 PM »
Cam housing.

I did a dumb mistake when taking my G54, so i will have to redo it.

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Offline Admiral_dk

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Re: Edwards 5 Cylinders.
« Reply #68 on: April 03, 2019, 09:26:20 PM »
I must admit that I can't see the mistake + can't help thinking - can't it be fixed without starting over ?

Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #69 on: April 03, 2019, 10:42:22 PM »
I must admit that I can't see the mistake + can't help thinking - can't it be fixed without starting over ?
I have a 0.027" cocentricity error.

When i did the second side of the part, i zeroed (in cnc language, we say creating the G54) the wrong way, then my part ended with up 0.027" off.

If you zoom on the seco d pic, you will see that the "ring" doesnt have the same thickness all around.

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Offline Admiral_dk

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Re: Edwards 5 Cylinders.
« Reply #70 on: April 04, 2019, 11:20:44 AM »
OK - I see it now and why you will scrap it. What can I say - Errare Humanum est …. we all make them.

Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #71 on: April 04, 2019, 12:30:38 PM »
OK - I see it now and why you will scrap it. What can I say - Errare Humanum est …. we all make them.
Yeah, like i said to my student:" Those who do nothing dont make mistakes, but dont do that error twice" :-)

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Offline petertha

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Re: Edwards 5 Cylinders.
« Reply #72 on: April 05, 2019, 12:56:51 AM »
The great thing about CNC is you can make scrap parts in no time flat. It takes me days to machine something & realize I buggered up! HaHa.
To make you feel good, I broke a tap off on the proverbial 'last hole' of my crankcase - I believe it was crankcase #3 sacrifice to the aluminum gods. Learned something every time.

Your radial is coming along great, look forward to your continued progress.
btw - what alloy did you choose for crankcase?

Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #73 on: April 05, 2019, 03:15:03 PM »


The great thing about CNC is you can make scrap parts in no time flat. It takes me days to machine something & realize I buggered up! HaHa.
To make you feel good, I broke a tap off on the proverbial 'last hole' of my crankcase - I believe it was crankcase #3 sacrifice to the aluminum gods. Learned something every time.

Your radial is coming along great, look forward to your continued progress.
btw - what alloy did you choose for crankcase?

Aluminium gods and me are buddy for quite some times ;-)

I'm using 6061T6.

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Offline glorfindel

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Re: Edwards 5 Cylinders.
« Reply #74 on: April 05, 2019, 04:02:42 PM »
Valve.

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