Greetings from Italy

Welcome Franz,

Your name sounds German not Italian!

Let us know what you are making with that lathe.

Ron

WELCOME TO THE FORUM Glad you decided to join in the fun!

Welcome to The CEF Forum Franz !!! Happy to hear from you , you sound like a engine guy .

Thanks to all the warm welcome!
Yes the nick name seems german but its only my italian name translated into German
My office colleagues began to call me in that way because of the fact that I project automotive components mainly for the German market .
I try to show some photo of my last work ….

Nice rear disc valve engine. Did you make it?

Welcome to the forum.

Yes i did it all by myself , its a 2.5 cc with zimmermann rear valve.
I had a "half idea" to take part in the Italian GIP 46 control line speed trophy, where rolling bearings are not allowed if using self-built engines.
So I tried the zimmermann valve as engine admission because I was hoping it would increase performance.
But unfortunatly the performances remained low anyway , with a graupner 6.5X6.5 and 10% nitro i can read about 15500 rpm ….i must definitely improve something ...

franzkleber wrote:Yes i did it all by myself , its a 2.5 cc with zimmermann rear valve.

Hi Franz,

Beautiful workmanship, and a very nice looking engine!

Have you flown it yet?

I know nothing about speed engines, but there are lots of speed fans on the forums.

Best of luck.

Bill

Here's your long awaited to The Forum!

That is some really fine craftsmanship there! Beautiful engine!

Looks like some Ron Valentine level work to me.

Welcome to the forum ... I'm glad you join, there are wonderful people here.
A pleasure to know about your work ... thanks for sharing!

Welcome Franz..I am particularly happy that a new member strengthens the growing "European section" of CEF. Italians and Hungarians have always been famous for our CL speed engines like Rossi, Moki etc.

And I could not agree more that COX engines are fantastic.

Also wanted to ask if you have tached your TeeDee09 with the 3D printed air scoop submitted to the COX Engine of the Month competition, and what your experience was? I would think that because of the ram pressure inside the scoop the static around the spraybar is higher than atmospheric so the atmospheric tank must be pressurized for a steady run?

Many thanks to all folks … unfortunatly i have to admit that i am very .... very far away from Valentine works !
I started "playing" with model engine only about 3 years ago …. and this "virus" has infected me deeply
I must say that I was lucky to meet an Italian guy who has been doing this kind of works for a long time, we live far away, he lives in Emilia Romagna near Modena but he became my mentor !
Last time we mets at a SAM 2001 Flying meeting its engine on the test bench exactly in the same conditions as mine exceeded 20,000 RPM!!
I was desperate and very disappointed moral of the story i have to work a lot more!

Also wanted to ask if you have tached your TeeDee09 with the 3D printed air scoop submitted to the COX Engine of the Month competition,
[/quote]


Hello balogh pleased to answer ,yes i tached it on the test bench only , with an APC 7x4 and a fuel 67 alcohol-23 oil-10 nitro i have seen a steady 15.600 RPM.
I find the suction very good , its start quickly and easily , and i want to try to increase slightly the venturi.
Now is equivalent to a hole diameter 2.9 mm (that is 6.6 mm2) i must check the original diameter on one new old stock engine ….. i think its a little bit bigger ...

franzkleber wrote:Also wanted to ask if you have tached your TeeDee09 with the 3D printed air scoop submitted to the COX Engine of the Month competition,

Hello balogh pleased to answer ,yes i tached it on the test bench only , with an APC 7x4 and a fuel  67 alcohol-23 oil-10 nitro i have seen a steady 15.600 RPM.
[/quote]

I forgot to mention that the glow head is COX original but as it burned ( ) I reworked it to use a standard glow plug OS P4 turbo

Thanks Franz. As far as my calliper goes into the 09 venturi I can measure 3.5 mm diameter.
Did you pressurize the tank when using the air scoop?
Yes the turbo plug is the right solution. Normal plugs in such small engines like an 09 are just performance robbers because of the gas volume captured between the normal plug and head threads that spoils compression ratio.

balogh wrote:Thanks Franz. As far as my calliper goes into the 09 venturi I can measure 3.5 mm diameter.
Did you pressurize the tank when using the air scoop?
Yes the turbo plug is the right solution. Normal plugs in such small engines like an 09 are just performance robbers because of the gas volume captured between the normal plug and head threads that spoils compression ratio.

Yes i am exactly of the same opinion , turbo plugs cost a little more but they are much better option.

The 3.5 mm sound right also to me , i will enlarge the venturi to 3.4-3.5 mm.
No pressurized tank because I'm not able to do and i like keep the think simple i am mainly passionate about engines and must confess that I did fly a control line airplane only once in my life with my 2.5 cc zimmermann , and after only 8 turns i broke the model in a bad Landing
I have to improve and learn a lot also in these fields ...

Franz in this topic below I described my experience with a similar ( but a bit stone-age) solution and others commented and added useful advice:

https://www.coxengineforum.com/t7472-compressor-charged-td049?highlight=Turbo+charged

Very Nice looking engine Franz ..  
I am not an engine builder but from the look of the parts they are very beefy as in the rod /pis assy thick crank web // all these will contribute to slower runs and the 10 % nitro have you tried or can you get 35% or higher nitro ( even if the event want allow it, if just to try ) The back plate of the fit to CC were the O ring is needs work as not to protrude out ... Just saying

Welcome Franz!

Very impressive work, is that your own design?

balogh wrote:Franz in this topic below I described my experience with a similar ( but a bit stone-age) solution and others commented and added useful advice:

https://www.coxengineforum.com/t7472-compressor-charged-td049?highlight=Turbo+charged

Wow you had the idea first and applied to a 0.051 TD!
One of the downside with my solution is the fact that it has become more complicated to cover the venturi to obtain more suction for an easy start … one finger is not enought and thepropelleris too close!
Still talking about the performance with 3.5 mm venturi and same fuel probably it can hit the target of 16.500 rpm …. i must try

KariFS wrote:Welcome Franz!

Very impressive work, is that your own design?

Hello KariFS , yes its all my own design and this explain also the low performance , it need some modifications to release all its potential but i am a little hesitant to make heavy changes.
Now it starts easily and makes a lot of noise and I like it enough .... i learn a lot and I will try to do better the next one ...

Franz put the bar higher! My 09 with stock carb swings a 7x4 APC prop at around 16k. I think this is basically what you may also read in the sceptre flight reports: http://www.sceptreflight.com/Model%20Engine%20Tests/Cox%20Tee%20Dee%2009.html


I think if the scoop really increases the airflow and the tank is pressurized a 18k speed with a 7x4 prop is doable!