RCV 120 SP props ?
 

Hi

I have got this brand new RCV 120 SP that I want to get running.
What size prop should I get ?
I have searched the internet, and I get everything from 18x10 to 22x18 props......a crazy gap.

I know that rpm should be at 500-5600 on the prop, but I dont have a bunch of high pitch props to test out, and they are very expensive to just go out and buy a few and try out.

I want to use it on a warbird, so it needs some speed. APC 18x14 maybe ?

I have bolted it on to my H9 Ultra stick for break in.



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While I'm not sure of the best propeller size, you've done the right thing:

Photographed the engine before running it as it will never be this clean again!

I'd suggest 18 x 10

here you go,,,
Jim

RCV 120-SP

https://www.rcuniverse.com/forum/glo...-vs-saito.html

https://www.modelflying.co.uk/forums...investigation/

Flying Sites - R/C Aero Portal - RCV ENGINES

Thanks, I have seen those. :-)
I was hoping for some practical experiance.....like " I have a spitfire and it flys great with a 18x14 prop "
But I guess not many fly these engines compared to the "normal" 4 strokes. :-)

I have an APC 18x10 in my prop stash, and will have to see what RPM`s I get out of that.
But thinking it must need a 14 og 16 pitch to get the plane moving when the prop speed is at half of the normal rpm.

A very interesting engine. Quite a feat, making that right angle turn with power delivery in such a lightweight and compact package.
The gearing places some pretty heavy demands on available lubrication no doubt.

I think it'll be OK... my 10,5 kg FW190 did pretty well with a 10" pitched prop spinning 5600 RPM on the ground (it gained about 1000 RPM in the air).
Different engine (ASP radial) but comparable RPM, and quite a heavy bird...

Went to the local hobbyshop, and they had a APC 18x12, so I bought that. They also have a 19x14.....but will try the 18 first :-)

We will see how it works out :-)

https://cimg5.ibsrv.net/gimg/www.rcu...162ad3d588.jpg
https://cimg6.ibsrv.net/gimg/www.rcu...b008ee9abb.jpg

Any flight video update!? Would love to see it.

Good news...I have not crashed it......because I have not flown it yet :-)
Sorry, I have not got it in the air or even had it at the field to run in. Hopefully when the snow melts again, 2024 will be the year.