The Le Rhone 9C

[MJM460]

Another of your interesting unusual engines.  It looks like it will be quite a challenge.

I will certainly be watching along.

MJM460

[kvom]

I wish I'd known R&T was on this year;  might well have attended.

Great project here.

[john mills]

this will be an interesting project i will be following
I wonder how they went building the original engines how did they make the cylinders and what numbers of these
engines were made it must have been quite a challenge with the materials and equipment at that time.
John

[Elam Works]

I wonder how they went building the original engines how did they make the cylinders and what numbers of these engines were made...

According to Gérard Hartmann in his monograph "Moteurs de légende : Le Rhône" 2004 it was "More than 10,000, including 5,600 in France by Gnome et Rhône from 1915 to 1917, 1,300 in Britain" No mention of the ones made in the USA under license. The 9J, 9Ja, 9Jb, and 9Jby (110 to 130hp) is given as "9350 ex (Gnome and Rhône), 1100 (Britain), Italy, Germany, Sweden, United States (1400)". The aforementioned monograph has a lot of background information on the evolution of the LeRhône, in French. However it is surprising how far you can get by running it in batches through Google translate!

The 9C (80hp) was certainly made in the USA, as seen in the first attached image.

As to the question of how they made the cylinders, turret lathes, lots of turret lathes. While not terribly clear in these photos, photos of other rotary cylinder fin cutting operations show the use of a gang of parting type tools. The LeRhône (and the Gnome 9B) had the boss for the sparkplug brazed in, so they could turn the upper fins uninterrupted. Engines like the Clerget required the top several fins to be milled so as to leave a island of material for the sparkplug boss. There is a video on the Imperial War Museum website showing the head fin milling operation on a Clerget cylinder head using an early vertical miller, starting about a 1:48 into the film. The rest of the film is interesting too. 

https://www.iwm.org.uk/collections/item/object/1060022698

Though I cannot see if a template or stops are being used to set the spacing and length. Examining the milling marks on the head fins of LeRhône 9C and 9J, they too used a endmill type cutter with a slight side taper and corner radius. However the fins on the LeRhône have an added complication of sweeping through an arc, to match the combustion chamber and have a uniform (approximately) cylinder head wall thickness.

-Doug

[john mills]

Thanks for showing
 each machine set to do an operation  and the part moved to the next machine for the next operation
basic machine tools just lots of them with lots of people to run them and lots to do lots of hand work.
John

[Twizseven]

Really looking forward to following this build (as well as Steamers and Vixens builds).

Love those old photographs.  Amazing what could be achieved back in those early years.

Colin

[lohring]

Those pictures bring back memories of the era when I worked in manufacturing.  NC machining was in its infancy.  Screw machines and turret lathes were the height of automation.  Those engines were made when labor was cheap and technology was expensive.  It was the beginning of more and more advanced manufacturing techniques.

Lohring Miller

[Craig DeShong]

What’d ya say?  Eh?... Eh?... EH???



I was fitted with my first set of hearing aids yesterday; as you can see, I went with the economy model. 

No, really; these things have progressed quote a bit since my Grand Dad had his pair.  Now they even have a smart phone App to monitor, adjust, and fine tune them.  So, I sat at Friday lunch today, amongst the guys, and fiddled with the phone app.  It’s kind of like going to the optometrist, is THIS better? or possibly, THIS? 

Regardless though, I will tell you that the world sounds significantly different with them turned on than off.  There is no ‘silver bullet’ to eradicate hearing loss; time will tell just how effective these things will be for me. 

On a less personal note, Thanks to everyone who is responding and especially to Doug, who added some additional historical information to this thread.   I appreciate all the added information that gives more relevance to this historic engine.

I started on the machining for the Le Rhone today.  I had an immediate false start when I turned on the lathe.  The sound it was making wasn’t what I was used to hearing and I stopped it immediately before I realized that it probably was the hearing aids, and when I turned the bloody things of; that suspicion was confirmed. 

Here I have a 5 ½ inch diameter piece of Aluminum chucked up in the lathe and I’m making a facing cut to square the end.  This will become the engine case after “some” work. 


Just a bit of work done today; as I stated the pace will be a bit slower on this build.  Here I’ve turned the diameter to the extreme outside cross-section dimension.  The outside surface of the engine case is sort-of elliptical in shape.  I’ve used a parting tool to establish the inboard diameter up against the lathe chuck.  Tomorrow Ill start whittling down this surface to form the outside contour.

[Brian Rupnow]

Craig--you are a bold man to set out on such a journey. Best of luck with your build.---Brian Rupnow

[steamer]

That's a mighty big piece of aluminum!   I'll in for the duration!!

Dave

[pieterb]

this will be interresting. I have a 1934 Gnome Rhone motorcycle. in their logo they used the aircraft engine (see logo on tank).

good luck

[ShopShoe]

That's quite a bike.

It looks like it includes lots of things that would have been considered advanced for the era.

I'm not a motorcycle guy but I like looking at the history of technology development.

If it runs I bet I would like the sound, too.

ShopShoe

[Craig DeShong]

Thanks for stopping by to see the latest.  Special thanks to:

Brian- I was looking for a challenge, hope I didn’t bite off more than I can chew!

Dave- I too was surprised how big it was when I picked it up from the supplier.   It’s big enough that I ought to be able to see what I’m doing when I make all those small parts that fit inside and whirl around. 
 
Pieterb and Shopshoe- interesting to see a Le Rhône motorcycle.  I hadn’t even though about what other products might have been made by the company.

Well, as promised, I spent a little time on the exterior of the engine case, trying to make a flat surface conform to an ellipse- biased toward the chuck side of the lathe.  I managed to hit my two outside dimensions and the middle dimension too.  This was more artistic work with some initial flats with the turning tools followed by LOTS of filing by progressively finer files and then some sand paper.  I’m pretty happy with the result.

[Admiral_dk]

Great result making a difficult 'organic' shape 

While I can do a decent single rounding by hand (90 degree corner to round) - compounded radiouses flowing together is altogether a different matter ....

I will also be in the Peanut gallery following this build    

Per

[Roger B]

I will be following with interest