Cox Sportsman .15 R / C and Homemade Muffler

Nice, good job, throttles real well. Did I miss the part where you made a rear carb intake?

Yes y no how loud the .15 is m'y self use mufler y have fit on the sportsman y did try rc wit carb fix wit pice tube just using the valve on the carburator work Good y have two of them tink of build model for them use twin .10 To .15

Cribbs74 wrote:Nice, good job, throttles real well. Did I miss the part where you made a rear carb intake?

Hello friend! ... actually now after a few years I have manufactured the silencer. It's what I show here ...
But the history of this engine and trying to control the speed, goes back a few years ago, where many members of the group gave me ideas of how to do it, it was then that Brad gave me the option of placing an air valve as shown here:
https://www.coxengineforum.com/t9410-video-cox-sportsman-15#119842
Based on Brad's idea, I started rehearsing and finally succeeded.

But as I said at the beginning, now I show the manufacture of the silencer.

1/2A Nut wrote:Very nice Mauricio a much more friendly engine with the header and
manifold keeping the tone of the exhaust easy on the ears! If you can
find these brass fittings makes for a simple solution for good breathing.

thank you dear friend

davidll1984 wrote:Yes y no how loud the .15 is m'y self use mufler y have fit on the sportsman y did try rc wit carb fix wit pice tube just using the valve on the carburator work Good y have two of them tink of build model for them use twin .10 To .15  

Hi David ... the engine works with great power, tomorrow God willing, I will do some flights!

Congratulations Mauricio. Is the muffler held down on the crankcase by the lowermost cylinder fin after you screw in the cylinder, like most of the COX mufflers?

balogh wrote:Congratulations Mauricio. Is the muffler held down on the crankcase by the lowermost cylinder fin after you screw in the cylinder, like most of the COX mufflers?

Thanks very much friend!.
No Andras, in this case it is held by the second fin of the cylinder counting from the bottom up.
It turns out that the base skirt of the cylinder is the same size as the bottom fin, therefore, as this muffler is one piece, the drilling does not stop or seal.
In the drawing you will see the sketch of how it really fits and is firmly fixed.
Points A and B were the idea of placing Oring in case it were necessary, but seeing the operating experience, everything is very well sealed and watertight, so that Oring is not necessary. Anyway I can place them as follows:
A) between fin 1 and fin 2, an Oring can be placed there
B) By making a groove in the muffler, an Oring can be accommodated.
But I repeat, A and B were an option in case of gas leaks and afterburners, but everything seems to go very well without them.

Brad the propeller is: Cox Grey 8 x 4

Well, the result in flight was perfect, the engine runs very well in all positions and acrobatics.
The engine sound improved considerably making it much more pleasant.
Here in this video, there are two flights, the first with zero wind and the second with wind between 35 and 40 km / h.
I like how this Cox Sportsman .15 engine turned out with a lot to give and enjoy ahead!

A very beautiful flight. It's been a long time since I flew a .15 sportsman or any other plane i
miss it. My controller fail lost signal twice with two different plane my secon controler is in drone reparation place for the seting of one of my new toys free style 250 drone y use m'y litle 4x4 Every day. since the last modification its lots of fun like noting To stop him

Flight with Snark 5T and Cox Sportsman .15 r / c.
Camera on board ..
an air record of our club, hangar area and our model airplane runway ...
I hope you enjoy the video...

Thank you Mauricio, very well done. It is quite energizing to watch such a flight in the morning when you wake up and check CEF entries on the telephone while still in bed!    

Where was the camera fixed on the plane, was it under the fuselage, crosswise? My small keychain camera sits mostly on the wing near the tip in order to avoid castor droplets hitting the lens.

balogh wrote:Thank you Mauricio, very well done. It is quite energizing to watch such a flight in the morning when you wake up and check CEF entries on the telephone while still in bed!    

Where was the camera fixed on the plane, was it under the fuselage, crosswise? My small keychain camera sits mostly on the wing near the tip in order to avoid castor droplets hitting the lens.

Thank you very much András for your comment, I am very happy you like the video.
The engine really works perfect, everything built into it like the air valve and the silencer seems to have always been there, since it behaves 10 points out of 10.
It allows you to make controlled flights and enjoy this powerful engine a lot.
Here I show you how to install the camera, everything is very simple. A plywood board, held up with rubber bands and built-in foam rubber to minimize vibrations. Everything turned out very well.
I hope you can and keep flying, I really wish it to be so!
Thanks again friend!

These dogs are here because people have abandoned them and they appear in the club, they become great friends, so there they are part of this wonderful hobby ... in this photo, waiting to eat!  

That was a fantastic flight video! Felt like I was in a passenger seat looking out the window. what Fun! Dancing with Dogs...not quite the same as wolfs but just as much fun.

Si cute This black white dog reminds me of my little doge a corgy galoi named cocotte y mis m'y friend Deceased 10 years ago
Look like

Marleysky wrote:That was a fantastic flight video! Felt like I was in a passenger seat looking out the window. what Fun!  Dancing with Dogs...not quite the same as wolfs but just as much fun.

Thank you very much for your comment Marleysky!! Thank you again ... I'm glad you like the flight!
These dogs are great, a bit of affection and they return all their affection ... there are 4 of them and they walk together throughout the club, there they have the whole property to run, they have water and food, so they have a great time.




Now I also have personal canine custody for my models hahaha    

davidll1984 wrote:Si cute This black white dog reminds me of my little doge a corgy galoi named cocotte y mis m'y friend Deceased 10 years ago
Look like

Thanks David, yes, animals are incredible beings!