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Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Sat Jun 02, 2018 4:36 pm

Thank you my friend Mauricio!  Smile

Guess what I moved the muffler forward some so it would spray away from the fuselage.
By doing so the rpm went up and I now understand why the most suitable position is
to have the exhaust ports front and rear facing so they split the flow evenly out the muffler.
3.75x3 / 4.25oz thrust / 34w / 63 mph pitch speed

+ 888 rpm. Bottom right diagram was the original position making 21,075 rpm.

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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  MauricioB on Sat Jun 02, 2018 11:19 pm

1/2A Nut wrote:Thank you my friend Mauricio!  Smile

Guess what I moved the muffler forward some so it would spray away from the fuselage.
By doing so the rpm went up and I now understand why the most suitable position is
to have the exhaust ports front and rear facing so they split the flow evenly out the muffler.
3.75x3 / 4.25oz thrust / 34w / 63 mph pitch speed

+ 888 rpm. Bottom right diagram was the original position making 21,075 rpm.


what a good find, friend !! .... the RPM has increased considerably ... it is clear that this will be a lot of talk ... I love to witness the step by step of these products!
Thanks for sharing!
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Sun Jun 03, 2018 12:55 am

Thank you yes just by need to divert the exhaust I stumbled on more rpm.

Note with a throttle sleeve and the same prop previously recorded.
Best read: 3.75x3 / 22,790 rpm / 65 mph this prop is best used for
thrust but has reach 91 mph pitch speed unloaded.

For a muffled engine with goo control the difference is - 827 rpm.
Not a bad trade off, if with a turbo plug that has a better adapter
fit will improve rpm further. The carb I am using lacks the precision fit
too and can be improved for better function. Another improvement for
better rpm is the spinner stock one sucks over bored so fits sloppy and
shifts when you tighten it down that wobble robs top end rpm and wears
down the crank liner faster. A bullet spinner with a threaded stud lines
up perfect. For now I only have the TD .010 and TD .049 sizes. I have
asked Greg to make them for the TD .020 will make the engine sing
and stop vibrations.

The TD .05 RC proved with pressure tap and Nelson plug one could dramatically
improve power. I saw around a 2k + static improvement with the combo that yielded
a max 141 mph prop pitch speed with the Nano IV down wind.
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  balogh on Sun Jun 03, 2018 9:36 am

Great experiments and results Brad.

I am looking forward to seeing your field vid.
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Sun Jun 03, 2018 3:32 pm

Thank you Balogh!!!  Beer Cheers

I had a air leak all this time and did not know it till I hit the field today.
Blowing air in the pressure line I could hear and feel air hitting my face
shocker! The aluminum tube from the vent line was bent down to clear
the muffler it had a crack just inside the firewall. I brought it home and
bent it back up straight and sealed with super glue. Now air tight.
I did try to fly it was acting up think the aluminum tube cracked during
engine runs. It was acting up so no good vid test to share yet.

I then had to take the RC carb off so I could clear the muffler from the
vent tube and put on a venturi. Cranked up the engine and the thing screamed
like the TD .050 does on pressure with the NANO III. Steady strong and very thirsty!
It ran good for about 35 seconds then blew the silicon pressure line off the nipple from
the muffler. Pooooof pop sound you could hear the pressure escape then the engine ran rough.
Same effect if on bladder pressure good steady fuel flow.

I put a slice of fuel line on the end of the pressure line to help keep it in place.
Then grabbed my camera and audio tach here is the results peaky NV with the
stock NV there is very little margin to set a steady rpm will need a fine 128 tpi
NV for the new RC carb to make setting range more broad. This is what I had
hoped for to mimic what was discovered with the TD .050 strong steady fuel
delivery with muffler pressure able to change with the throttle position will
be ideal. You get the same effect with a tuned pipe except even more so as
the pipe acts like a pump and draws fuel / air through the intake. Micro beast
power, with a bearing case the engine can handle the rpm without so much
heat build up.

Good clear pic of the launch:


Here is my fix to keep the pressure line from blowing off.


Most common read shown in pic and peaked hit at 25,032 rpm/ note the NV is hard to reach.
I had the plane setup for a left hand NV so to avoid hitting a finger the extension was added
I hate extensions bad on the NV. The tube can be pulled off once you have set it for field flying
per day as there is very little need to keep messing with the NV when using pressure. The muffler
is canted forward crowding the NV but did that to help get the spray further away from the fuselage.
Greg may provide a side exhaust insert for the muffler if so the NV will clear just fine.



Last edited by 1/2A Nut on Mon Jun 04, 2018 2:44 am; edited 2 times in total
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Sun Jun 03, 2018 8:09 pm



Published on Jun 3, 2018
Chasing the NV needs a 128 TPI  to get more consistent.
Yet to the ear the engine sounded steady singing along.
Not bad though testing found if you leave it a hair rich it
will ride the rpm spikes better heard more so by the tach

3.36 x 4.5 prop. Good rpm for the load and having a muffler.
2nd cylinder tested, exhaust port direction makes a difference
in max rpm. Best seems to be fore and aft. to split the muffler's header.
In the air it should sound seemingly more steady as the unloaded state
will hide the rpm spikes more so.

Given the above bench test, note flight test last weekend with a throttle sleeve:
Published on May 28, 2018
TD .020 / 3.37 x 4.5 Prop best peak hit 28,585 rpm / 122 mph pitch speed.
Best static in the hand at launch 23,192 rpm / 99 mph pitch speed

The muffler with pressure is exceeding the throttle sleeve.  
test 2 cylinder: 23,417 / test 1 cylinder: 24,387 (indoors)
Yet to test a fore and aft exhaust port cylinder should do the best.
Outside temps are very hot I don't expect to maintain as much rpm
will take the best cylinder arrangement to stay well ahead of the sleeve.

Small Cox Logo RC Plane


Last edited by 1/2A Nut on Thu Jun 07, 2018 8:59 pm; edited 1 time in total
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Thu Jun 07, 2018 1:43 pm

Will be building a better size Nano for the TD .050 to yield more speed:

Best pitch speed with good thrust per posted vid during testing with the Nano III hit 139 mph.
Time to reduced size and weight looking to drop off 1.4oz the plane should hit closer to 150 mph
pitch speed with the same prop a 4.22x5.5 target is 28,800 rpm.

The .049/.05/.051 engine size will be called the NANO X
A cnc header and Profi tuned pipe would be the next step for TD .049 /.05 and .051's:


Clearly a missing link here between the piped car engine and the TD .020 plane.
Showing 28" span / 19.5" and 15.5" span. A Norvel .061 would work in lieu of a Cox engine.
Goal is .010 / .020 /.05 and .09 size planes honed to best proportions powered by iconic Cox engines!
The Norvel .074 would be perfect for the 28" plane the span can support the weight with ease.
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Mon Jun 11, 2018 11:46 pm

This is how I start the fuselage simply blow up to scale on my computer monitor and copy to paper.



These are my templates from the built / flown projects and now the NANO X

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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  balogh on Tue Jun 12, 2018 12:25 am

Brad
I like these simple yet great ideas!
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Tue Jun 12, 2018 12:49 am

Thank you András,  Hand Shake yes these planes are simple to scale up or down in size
and strong using ply and spruce square stock for the fuselages.

I will have to do a NANO V for the TD .09 at some point.
It will go faster than the DART as the airfoil will be thinner for more speed and
100 sq. in wing 32" span, target weight 9.5oz dry. Another option since I have
done the .09 DART is a NANO for the TD .15 big power with many more props
that could be tested 6x7.5 at 24k / 170 mph / 274 kph would be worth doing for
windy / gusty days. Should do 150 mph into the wind.


AmpAbuser
Published on Jul 2, 2016

Best level pass 143mph / per prop calc / APC 5.25x6.25E
Wavescope: 232.07 kmh / 144.2mph /down wind  / 21,960rpm
The reading was taken at 1.52mins into the vid. Temp 96F
Static 17.1k rpm at launch / 9.52oz / 101mph / .167hp / 125w
30% nitro / 20% castor / 31.5 inches 106 Sq. In. wing / 11.7 oz RTF
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Tue Jun 12, 2018 3:55 pm

I am curious about the size of a NANO V / TD .15 size plane here is what happens
when I scale it up to size. The .15 is truly a beast of a engine making the TD .09
look like a .049. The engine as shown weighs 5.1oz with prop / spinner, target
weight maybe possible. A radial mount for this one would be kick arse!



Tested a 3.23x5 prop cut down from a 5x5 results seem good for speed.


Small Cox Logo RC Plane Small Cox Logo
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Happy Re: Cox .01 /.02 /.05 Engines & Mods / Nano Speed Planes

Post  1/2A Nut on Wed Jun 13, 2018 4:31 pm

Sad if you do a search for RC flying sport planes with TD .15 engines on the nose there are no Youtube vids.
Here is a size comparison from the other NANO's looking forward to building the NV.
The N-III is ok for a Norvel .074 and would be a easy lander if on the .09 size plane.


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