RR Merlin….

I’ve looked at this comment several times and thought it didn’t sound right.
Having finally read it again with my brain engaged, for 8 thousandths, read 1/125th.

1/125 = 0.008

a rose by any other name 😉

The same chap who built the Merlin has done a RR Eagle 22, which is similar to a Napier Sabre but bigger and powered the prototype Wyvern. That’s double the parts of the Merlin. And what’s even more incredible is that these engines are exact replicas, not just externally similar.

Look At this link http://www.enginehistory.org/model_engines.htm

Be sure to look at the movie link and internal photos.. WOW 😮
Jimmy

Hang about. Not the Jimmy Page?

too bad he didnt have a real electric start!

Now , how about an R-4360 28 cylinder, 1/5th scale…
That would be impressive !!!!!

If it is 1/5 scale then the capacity should be 8 thousandths of the original and consequently the fuel consumption would be about the same if the rev’s were kept as per the full size. However, bearing surfaces would only be reduced by a factor of 0.04 so friction would be a significant factor….waffle …yawn…. wouldn’t ya just love one in an RC flying Spitfire….

I’ve looked at this comment several times and thought it didn’t sound right.
Having finally read it again with my brain engaged, for 8 thousandths, read 1/125th.

does it also use scale oil?

That’s what fish use. 😉

Looks like it’s liquid cooled to me. Doesn’t it just sound unreal !!!!!
I want one
I want one
I want one

Is this small Merlin (nearly called it a model) liquid cooled, does it also use scale oil?

I saw a 1/5 Merlin at Old Warden in about 1983. There was also a similar scale Gnome rotary. Both were run. The Merlin was impressive to say the least. It had that Merlin sound but just an octave higher! Imagine listening to sound recordings of a Merlin at 45rpm (for those than can remember pre-CD) instead of 33rpm.

It even had that great popping exhaust sound when it throttled back. It was one of the best things I have seen at a lot of shows I have been to over a lot of years!

Melv

Here is the a link to the other scale merlin ‘kit’
http://dynamotive.netfirms.com/merlin/

Jimmy

Ive seen previous photos of this engine before stating it was 1/4 scale.. To me it looks more 1/4 than 1/5.. Just look at those close up photos..
Dont see why he went to all the trouble to build the engine and then not have a scale starting system… Mabey an electric starter was too complicated for him to build 😉
Brave man to swing the prop by hand I must say

Also on the net ive seen a guy in the states who had started to manufacture castings for a 1/4 merlin kit but if I remember rightly it didnt have scale internals like this amazing master piece..

Thanks for the info. Love it.

Slipstream: I hope your information is correct, because I will be repeating it parrot fashion at dinner parties when I want to impress!

I wonder what the constraints were on the builder of this Merlin model that made him choose that particular scale.

Janie..’tis all true, volumes are a cube function, areas are a square function. I am not sure what constraints were imposed, there may be a convention in the model world that dictates 1/5 scale. It would be more practical but more expensive to go for a larger size from a metalurgical aspect and where tolerances become less critical. The closer to full size you go the easier it is to adhere to the scaling factor on component parts. For example, a 2mm thick piece of dural is fairly stiff, reduce it to 0.4 mm and it bends like kitchen foil. This means that, for example, conrods that were made of aluminium in the original have to be made of steel in the model.

This will either impress or force a change of topic at your dinner parties 😉

Slipstream: I hope your information is correct, because I will be repeating it parrot fashion at dinner parties when I want to impress!

I wonder what the constraints were on the builder of this Merlin model that made him choose that particular scale.

I wonder if the fuel consumption is one-fifth of the original.

If it is 1/5 scale then the capacity should be 8 thousandths of the original and consequently the fuel consumption would be about the same if the rev’s were kept as per the full size. However, bearing surfaces would only be reduced by a factor of 0.04 so friction would be a significant factor….waffle …yawn…. wouldn’t ya just love one in an RC flying Spitfire….

A stunning piece of engineering that…

I want one of those.
I wonder if the fuel consumption is one-fifth of the original.

Heard about this but never seen it. Speechles 😮