New Flight: Pitts -Skelton Aerobatic model (page 9)

Thanks András!
The idea is to prolong the muffler's output.
I have verified that with a piece of neoprene the engine drops about 500 rpm, so I am going to build a pipe or something that can evacuate the gases without the engine losing laps and not lowering performance.
The idea is to get the gases out of the cowl.

Aeromodelling masterpiece!

Thank you very much Levent, very kind your words ... it makes me very good to know that it is a work that is appreciated by you.

Mauricio instead of using a small diameter extension, why don't you add a large diameter silicon exhaust extender of a larger engine? The impact on the rpm is less than with a small dia extension. The small exhaust outlet stub on the muffler needs a few layers of silicon tape wound around it so that the extender can be fit snug.

While the fuselage rests from my hands I think about the wings of this beautiful model ...
Ribs or foam ... mmm ribs or foam ... I like wooden structures and ribs, but for a matter of robustness and effort, I decided on foam.
I must build it light and resistant at the same time ... here we go!












Good friends! ... I have my wings cut ready to be plated with a raft ...

balogh wrote:Mauricio instead of using a small diameter extension, why don't you add a large diameter silicon exhaust extender of a larger engine? The impact on the rpm is less than with a small dia extension. The small exhaust outlet stub on the muffler needs a few layers of silicon tape wound around it so that the extender can be fit snug.

Yes András , as you comment, the discharge diameter must be greater so that there are no restrictions on the gas outlet. Thank you for your collaboration ... I will evaluate how to do it.

Dear Andras, I have taken your suggestion and got to work, then:
I made a quick coupling by pressure, which is nailed automatically, being very firm.
  This accessory allows you to position the baffle with a larger diameter and hold it firmly, and then a plastic seal is placed on top
I made some adjustments to the hood and it is finally very well installed.
Thanks again András for your collaboration .

What can I say Mauricio? Again a solution you have implemented to perfection.

I use these larger exhaust extenders on my TeeDee 09 engines for castor splash control and they do not seem to reduce the rpm further than the muffler already does on the SPI cylinder..

This is one of the most innovative and finely crafted models I've seen! Go Mauricio!

Mauricio you may want to use an additional zip-tie to fix the exhaust extender to the motor holder firewall box, because its weight and vibrations may force it, together with the removable NV muffler end, to drop...I tend to lose these extenders from my OS Max 56 Fs if not fixed with additional zip tie..

Thank you Tee Bee for your words, thank you very much !!

balogh wrote:Mauricio you may want to use an additional zip-tie to fix the exhaust extender to the motor holder firewall box, because its weight and vibrations may force it, together with the removable NV muffler end, to drop...I tend to lose these extenders from my OS Max 56 Fs if not fixed with additional zip tie..

Thanks András , here I leave photos that explain how it is firmly and secure, from there it will not escape.

In the meantime to entertain and since I am showing the Norvel engine I leave here a contribution:
The Norvel .061 engine is the hardest engine I have ever had when it is new or not running. It has a big pinch or anchor in the top dead center, which nails in when it's new in an amazing way.
So this is the process I do to seat or roll a Norvel engine for the first time. The videos are not edited, they are in real time, so the process is long, but really worth it.
If it is of your interest, watch the videos and enjoy them, I hope they are useful.

Part 1:


Part 2:

Airplane is looking SWEET Mauricio !! I am surprised you went with foam wings but am sure they will look great , i remember when you made the cutter and it does a very good job with your guides, I will check out the videos in time Thank You Friend !  

Eric friend, of course you're going to see it in flight, let's make it so.
Yes friend, I decided to make them in foam because according to my calculations, for this wing size, I will achieve greater resistance at a lower weight or similar with foam than if I make a rib and stringer structure.
Remember that the wings are going to have reforms to be able to have aileron control (4), so if the rib wings had points to reinforce that are not convenient due to weight.
Making them out of foam, I can handle a light structure and strong enough so that the parts of it do not flex.

OK Makes since and drop the K i am a man LOL , Eric

getback wrote:OK Makes since and drop the K i am a man LOL , Eric

Eric my great friend, I hate not knowing how to write, I hate not knowing the name of each person I love, I hate not being able to hug when I feel like doing it ... ERIC, [bleep] the K I already did.
Now you've given me an idea ...

Wing plating process ...1mm thick balsa veneer




gluing leading edge and trailing edge
now wait for the glue to do its job ....




I hope I don't bore you, I hope I don't tire you ... I'm really enjoying this project with you!

Mauricio ...brother...you are one of the few CEF master builders and story tellers....I doubt any one is bored of YOUR posts....seriously sir

Please keep feeding us your exquisite builds, engineering challenges, and beautiful finished models

true craftsmen always will inspire other modelers to self innovate, or copy the master

Oh, I'm not bored.  I really enjoy watching your projects go from plans to flight.  Thanks for taking the time to take photos, write the descriptions of what you're doing and then posting them.  I know it adds quite a bit of time to the builds and it really is appreciated.

Please proceed sir.

Thanks guys for your kind words! ... then time to continue with the progress ...
The central rib of the upper wing is made of very hard material, it is a plate for making electronic circuits, the same on one side has a copper foil that adds to the resistance, but it is still light at the same time.
I could make it out of wood, but I like the strength and resistance of this material where the wing is attached to the uprights:


the holes that I show there, are made so that the epoxy that I will apply passes from side to side and thus there is a communication of the glue.
Once each semi-wing is joined, it will have a fiberglass sheet on the outside, we will see this later.



Well, here is a presentation of the wings ... I have to finish the leading edge, trailing edge, marginal edge, but this is what they look like now:


The wooden bolts that you see there will not remain on the wing when you close it, they are only placed now in order to align and get an idea that everything is in place:


so far this structure has been installed: the complete motor, propeller + tank + cone + bedplate + gas deflector + dural train + wheels + wheel covers.
It would be missing to place 5 micro servos + battery pack + key on off + RX + cover the complete model + figure of the pilot.
The weight the moment is: 392 gs = 13.8274 oz



So you can see then how the PITTS looks:



   

The Pitts is looking GOOD !!!