Cox .01 /.02 /.05 /.09 /.15 Speed Planes

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.

Great experiments and results Brad.

I am looking forward to seeing your field vid.

Thank you Balogh!!!  

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.

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.

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.

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

Brad
I like these simple yet great ideas!

Thank you András,   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

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.

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.

What is this, what do we have here??  

A big brother radial mount for the Medallion and Tee Dee .09!!!

Finally a fast way to adjust your nose heavy plane or to stream line for direct
firewall mounting, less load on the firewall, less vibrations to the airframe nothing
sticking out more than necessary always a big plus and you save the weight of
a engine mount / less stress the the firewall now a optional way to mount a engine
for CL use and for hard core FF planes. If you have a smaller engine hanging forward on
on a engine mount and need some extra power the .09 up against the firewall maybe
tucked in enough to allow just a RX battery shift to set the CG.

I plan to cut the beam mounts off and polish as done with the TD .051
Note Greg has made this one with additional beef to support the power of the TD .09!
Buy there here is the link this link will expire once the sale time period has ended but
you can always go to his main sales page to find the new link for them. For mounting
just hand tighten the mount, then with two screws mount the engine to some sacrifice
wood and use the cylinder to final rotate to a snug fit. From there you can now line up
the engine on the firewall to locate the best holes for final placement

Aluminum Backplate Radial Mount for Cox Tee Dee / Medallion .09 TD

https://www.ebay.com/itm/Aluminum-Backplate-Radial-Mount-for-Cox-Tee-Dee-Medallion-09-TD/202350220511?_trkparms=aid%3D777003%26algo%3DDISCL.MBE%26ao%3D2%26asc%3D52910%26meid%3D71d76410b3a8436a8110d89872689da7%26pid%3D100012%26rk%3D1%26rkt%3D12%26sd%3D202348533184%26itm%3D202350220511&_trksid=p2047675.c100012.m1985

Main Page for all parts relistings:

https://www.ebay.com/usr/gkamysz?_trksid=p2047675.l2559




More goodies to come keep watching this thread !

   

That's pretty slick Brad , and the new mounts look good Greg. Brad do you know how much weight you lost by removing the radial mounts on the CC ? still looking for those bird cages too .

Thank you Eric, I took a grinder to the lugs did not do a before and after check on the scale.
You can figure the lugs gone make up for the extra metal for the radial mount which is 6.1g
Stock backplate is 3.7g so a mere 2.4g extra (most excellent) you save the weight of the nylon
engine mount which is heavy and requires 8 metal screws in total in order use that method!
Major weight savings when performance is everything. The new mod will have me back making
a Nano .09 version to break my current speed record with a Doppler pass at 144 mph.
Solid mount means the engine will sing a higher note giving additional top end rpm.

This particular engine with the RC carb, 6.25 x 3.25 combat prop (6.4g) and stock spinner is 91.8g
Stock carb body and high comp head. I will bench test this combo at some point. The prop
is designed for 35k rpm with a high performance .15. I want to use it to produce 2 lbs. of thrust.
Will make a great acro prop with a mix of speed potential to 80 mph down wind.

Another piece of the puzzle came in the mail today a nice aluminum carb body.

Brad, the purple is quite light on pitch. Have you ever tried the green? Hmm seeing your above pic shows it listed as 3.25. That's about equal to the green as my purples are about 2.7.

I bought a batch of these off of ebay from a combat guy in Texas he has more for sale if interested.
Listed as 6.25 x 3.25  This prop would also be good for a SH -07 or a Norvel .074 and  Vmax 7 for RC use.
Could not resist 24 bucks for 5 props shipped / 4.80 a prop.

I have some green ones 4.96x2.75 but they are for 1/2A engines.  

F2D Combat Free Flight Propellers. 5 Props Per Order:

https://www.ebay.com/itm/F2D-Combat-Free-Flight-Propellers-5-Props-Per-Order/183095615665?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649


These are better for the .09 and .074 RC use.
I would like to try some but really for TD .09 RC speed would need 6.5" pitch.



http://www.best-hobby.com/shop/propeller-nn-f2d

AmpAbuser
Published on Jun 30, 2018

Cox Tee Dee 09 RC / 6.25 x 3.25 Glass "NN" combat prop
Static Peak: 18,733 rpm /25oz 1.6lb thrust / .234hp / 175w / 58 mph pitch speed.
Bench testing after brief break in period of 1/2oz rich /NV set to steady top end
still a bit rich to be on the safe side till full break in.  
Radial mount, Tarno .09 RC Carb, High Compression Glow Plug.
2 plug shims / 25% nitro / 20% castor. Muffler spring steel slider ring closed to
minimize sound expect open exhaust a good 1,000+ rpm increase.

Brad is your 09 an SPI engine? I have a similar config on my Cosmic Wind and Wonder planes and I measure around 15k static with a glow plug adaptor, a 7x3 Graupner prop and 20% nitro. I also have a muffler extension silicon pipe to keep gunk away from the fuselage.

The glow plug robs quite an rpm compared to the highcomp stock head but the idle with the latter and 20% nitro is not stable.

I like your 09 Tarno carb that I only have in 049 size...hunting for it on ebay without success so far.

Thank you, yes it is SPI as this was never a TD RC .09, I have two of those ready to go.
The only reason why I benched the engine with that muffler was to reduce noise.
I would much prefer a header and manifold arrangement to keep the rpm levels up.

This engine is set up for max cooling using an all aluminum case, it will be a speed engine
for a NANO style plane. The extra grunt of the TD .09 will be perfect for windy day flying.
The NN props make good thrust to punch through heavy wind. This time of year I am getting
constant gusty winds daily grounding me from flying smaller planes. Today gusty to 27 mph.
Some days are ok Sunday will be good in the morning, hits 102F in the afternoon ugg.

Do a weight check on your 7x3 Graupner prop. Compare to the NN glass prop at 6.1g
I have a Turbo plug adapter and was able to get 144 mph with the DART .09
For sure will be using the turbo plug adapter for the NANO project, leaner lower weight then
the DART the NANO should be next level in speed.

The Tarno .09 RC carb is very rare to find on ebay, average 1 shows up every 3-4yrs. if your lucky to spot it.
You can thread a standard carb stem as an option, I would recommend a aluminum carb body for long lasting always.
Supports the weight of the RC carb better. Another option if there is enough meat on the bone is to bore out the
threads in the aluminum carb body and with a O ring on the carb stem push fit and run a small dia. bolt through the
carb body to hold the stem in place. The Enya TV .09 carb will work for this retrofit.

If using a standard glow head adapter I would make sure you are only using 1 head gasket and oil the threads to help seal.  
Another top tip is use black oxide high strength bolts no warping under load less spinner slop.
See pic the stainless steel bolt is .133 dia. the black oxide bolt is .136 for a better fit in the spinner
and for a less sloppy thread fit in the crank shaft. It adds rpm by reducing vibration / heat and wear.
The bolt must have some non threaded area to help gain a slop free spinner.

Thanks for the tips Brad. Yes I have a hex socket head bolt from Matt and will get another one. Do you know who makes turboplug adapters in 09 size? Your Lubbock neighbor Kittingittogether only deals in 049 sizes?
Matt sold me 2 COX RC carbs in 09 size and because they have more meat around the airbleed bolt and idle bolt than the 049 carb they hold out better.

I will also check the Graupner prop weight.
You may recall from my Cosmic Wind and SIG Wonder projects that I have a garage-tuned 09 cylinder with booster grooves added by the previous owner. Well this one actually gives less rpm than my stock cylinders. I suspect the home made booster grooves may extend to the exhaust port top level and the timings of charge and exhaust may slightly overlap too early thus cylinder pressure not yet relieved by the exhaust opening may force gases into the crank?

The bolts need to be black oxide treated for the additional diameter otherwise there is extra play in the spinner hole.
Must have none threaded surface at the top of the bolt near the hex head in order to further reduce the slop.

No I do not know of anyone making turbo heads now. Mine was made by Ronald Valentine you may ask him or Greg.
Yes it is possible the booster flutes that the previous owner of your engine may have milled the height wrong and your
getting blow by / loss of fuel draw to get some power back perhaps a pressurized tank may help.  

Another top tip if you wish to improve power.
I have modified my stock muffler. It now has pressure tap and still retains a adjustable exhaust able to choke it down
to minimum noise for bench testing. One thing I did was reduce the diameter of the spring steel by coiling it in smaller
in dia. By doing that it grips better around the manifold and will stay put. The cylinder ports are facing in a good direction
splitting the opening in the manifold. That has one cylinder port facing the pressure tap so I expect good fuel flow.
The pressure tap has 4mm threads and goes into the existing hole that was made by the exhaust tip. The manifold
is too thin walled to support the pressure tap threads so I secured it to the manifold with a nut. Using a L shape pressure
tap you can rotate it up close the the RC carb without any issues with the feed line back to the tank.

Also to my shock the glow head was loose from the bench test. I should have checked it after the run least I know now.
Will do another bench test to try out the modified muffler. Goo control to one side of the plane with pressure good to go.  

Yes I also reduce the slide ring  diameter by coiling it. In addition I  wrap the slide spring in thin silicon strips used by plumbers to increase goo control because the metal contact between the slip ring and the lips of the muffler opening does not seal well.

I like your pressure tap addition. Did you use the stock hole for the muffler header that you removed?