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Jul 30, 2016, 05:29 PM
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The re purposed long reach prop retainer nuts came in they fit like a champ woot!
Now the thicker hub APC props can be used. The nuts are made out of aluminum so
no weight penalty and reach all the way through. Test flew with the 5x4.5N the thicker
foil and more heavy prop only hit 111.22mph. The correct speed tip props came in lower
weight at 2.7g should be a drop in for the Fuji motors. Thrust was much better nearly
1:1 ratio. With the uncut speed props should bust 1:1. Pic of the very fat hub of the APC 5x3
great thread bit all the way thru. The washer works great as a stop for the start cone of
the Hornet 1/2A starter cone is flipped around using the small hole starts easy with no wear
against the prop. The thick airfoil creates great thrust for controlled sport racing. Better yet
for the first time I can use my custom cut carbon props such as the speed 4x5 shown the hub
bore is a perfect snug fit. 6 mm / .25in OD is the long reach prop nut. If at 32k / 152 mph.
Updated the STUMP design so I can use a pilot in the cockpit/ airfoil has been scaled to 2in
aileron stock.

Bench tested the correct 5x4.5 no back cut the lower weight and thinner blade allows good numbers
Static 20,752 rpm / .181hp / 135w / 12.3oz thrust / 88 mph.
Last edited by 1/2A Nut; Jul 31, 2016 at 03:09 AM.
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Jul 31, 2016, 12:11 AM
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DART - Fuji .05 / Profi Tuned Pipe HQ 5x4.5N Fast Speed Passes (9 min 9 sec)

Per doppler wav scope - 181 kph / 112.47 mph
Better thrust lower idle.
Last edited by 1/2A Nut; Jul 31, 2016 at 01:08 AM.
Jul 31, 2016, 02:15 PM
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Tested the correct HQ 5x4.5N
Static stock 23.66k with back cut 25,759 / 18.7oz thrust / .346hp / 258w / 110 mph
Clearly the prop calc has been fooled by unique narrow prop design this engine typically
only puts out 130/140w thrust so has leaped up / typically 12oz. It did kick in on the pipe
at these rpms. Will do a flight test today looks very promising. Sustained vertical with
high speeds is the goal est. unloaded down wind 31.6k / 135mph making it a superior
1/2A plane with freight train mannerisms, punchy upwind speeds, consistent full field
performance with an excellent idle. Two other changes made prior to testing I added
some fuel line to seal the NV and using racing blend more suitable for car engines
10% synthetic 10% castor 30% nitro. The thick castor lags the engine rpm and gums up
the bearings the engines con rod and pins gets stressed by this was the right move to make.

Update field tested the unloaded rpm.
Best pass was nearing an empty tank state.
32,079 rpm / 137 mph. per prop calc.
2nd best was 31.8k best pass parallel to the wind was 30.9k / 132 mph.
The 1/2A world is lucky to have an infusion of modern composite props to play with this is the results of my efforts.
I have tried many props and pretty much exhausted the last bits of possible speed with the .09 size plane it is time to
move on to another project that best utilizes the power of the Fuji .05 truly impressive engine and ease of use if
following my suggestions for parts used on the engine mentioned on the previous page.

Some pics.. last one fast full throttle pass up close as I dare.
Lastly the engine has been removed cleaned, reweighed and bagged up, here are the results.
Last edited by 1/2A Nut; Aug 01, 2016 at 12:17 AM.
Aug 03, 2016, 10:07 PM
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Cox TD / Profi Tuned Pipe / 25,193 Static - HQ Prop 4 x 4.5 (0 min 24 sec)

Published on Aug 3, 2016

Cox TD .051 / Profi Tuned Pipe / 25,193 Static / HQ Prop 4 x 4.5
Static 7.3 oz thrust / .132 hp / 99w / 107.3 mph
9.3in MRP / 140 deg timing / Pipe set for 25,215 rpm!

Fuel line was a bit big for 1/2A use / pressure line was correct.
For flight prop HQ Prop 5x4.5 will unload near MRP and produce
est. 11 oz thrust. Non SPI / 20% oil / 30% nitro.

Cox TD .050 Idle Testing / Profi 1/2A Tuned Pipe (1 min 34 sec)

Published on Aug 4, 2016

Late at night had to keep the noise down good time to set up the idle.
I did run it up till it caught on the pipe to show good transition back to idle
Noise had to be kept down it was after midnight. When bench testing best
to keep the pipe pointing down to avoid oil build up. Will be making one more
bench test vid showing best possible tuning for low and high end during
regular daytime hours. This is the cleanest running Cox engine to date
with 85 -90% oil going out the pipe!

Tarno Carb from Canada with air bleed. 20% castor / 30% nitro.
I used proper 1/2A fuel line and didnt need pressure it draws just fine
with the smaller line the Tuned Pipe acts like a pump drawing fuel / air in.
I recommend not using pressure with a RC carb as the pipe does a good
job on its own with this small size engine. I do use pressure with my
Fuji works great the Cox engine is a different animal.

Key things:
- Non SPI
- Use a cylinder with the exhaust facing back
- Use a brass C shape shim to block the channel in the Cox car muffler
- (this only allows one open exhaust port)
- Strive to have a clean transition and use a file to open up the stock muffler.
Last edited by 1/2A Nut; Aug 05, 2016 at 02:11 AM.
Aug 06, 2016, 10:23 PM
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Picco P-0 .05 / Profi Tuned Pipe - APC 4.2x4 / 28,585 Static (0 min 51 sec)

Published on Aug 6, 2016

Picco P-0 .0519 Cu. In. /.85cc / APC 4.2x4 / 28,585 Static
11.9 oz thrust .209 hp / 156w / 108.2 mph
- Mecoa Toki / Fuji Muffler APC 4.2x4 / 26.570k Static

If tested with the lean carbon HQ Prop 4x4.5 the rpm would bust 30k
Last edited by 1/2A Nut; Aug 06, 2016 at 10:30 PM.
Aug 08, 2016, 01:43 AM
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The Picco P-0 a known power house shall be up for field testing next first flights will be for base line data APC 4.2x4 should do around 33k. After that only low weight carbon composite props will load the axle starting with a 4.5x4.5 and finally a 4x5 should see 145+ To this day no one has a posted video of the Picco .05 flying a plane on YouTube. There are a few bench test vids here there but nothing in the air.

This was promising a Delta Force Vortex Micro Hydro till I realized he had no running vid on the water what a crying shame! The engine is a bit over propped by the looks of it using a 05 can motor prop x431 for a .05 IC engine is asking too much the torque is simply not there. 1622 aluminum alloy 2 blade surface prop would be my choice for a nice 45-60 mph outrigger micro hydro. The boat is using the wrong hardware just too big and heavy for the engine. Perfect for a .09 to a .12 The water cooling head was special wish I had one.

P1000638 (0 min 58 sec)

Bingo - Magic Time Picco .05 being used in something other than a RC car:

Picco P-Zero by M2MAX. (2 min 20 sec)

Published on Sep 24, 2015
Saint-Savinien SAW 20/09/2015.
Picco P-0 / .0519 Cu. In. /.85cc
33k + average
Best 36,014 rpm
Best 44.7k no load

micro H 0,8cc (0 min 55 sec)

french saw 2015 max 0,8cc (2 min 5 sec)
Last edited by 1/2A Nut; Sep 29, 2016 at 05:23 AM.
Aug 08, 2016, 07:57 AM
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P1000638 (0 min 58 sec)

That video was made in 2009, wonder if he actually ran it on the water?
Aug 08, 2016, 08:04 AM
Registered User
You would probably have to make up a water cooling head. With all the heat sink heads now, I think I would just go that route on a boat. No drag from the pickup tube, and all the tubing etc. They sound pretty good in the boat. I would worry about the weak crank.
Aug 08, 2016, 08:10 AM
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I did a full search and never found the running video for the hydro it has promise although the rigger is much better
on keeping the load off the engine.

Perhaps his version doesn't have a weak crank I asked Maxim for the build thread here it is he has some pics
and info worth reading / seeing. He uses a toothed belt drive for starting easy on the crank that way. Much
less pressure needed unlike a flywheel. He doesn't even use any real flywheel. Weight of the coupler and cable
metal prop are mass in their own right along with the S bend this helps keep the engine from going ballistic when
the prop jumps out of the water.

Note: He used a Octura X427 prop reduced / reshaped.
Possible speed 1.4in x 36,014k rpm 48 mph
Most of the run was averaging 33k + his car pipe is set up to run that rpm.

I used the translator good info as they figure out what works with the engine.

Something fun:

Manned multirotor part 12 Flying and tuning in 1080p! (11 min 23 sec)

The Smallest RC Engine In The WORLD! (2 min 9 sec)
Last edited by 1/2A Nut; Aug 25, 2016 at 12:00 AM.
Aug 21, 2016, 02:04 PM
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Some of my gear came in the mail still waiting on a rudder assembly.
Renderings so far, set up one of my Picco's and Profi tuned pipes. A full
wave pipe should make more power than the car pipes. Not sure which
design I will go with stability, low weight and proper ride angle is key for
top end speed. 1/2A rigger will be nice addition and something to do when
the wind or wet weather stops me from hitting the flying field.

Picco p zero outrigger hydroplane (1 min 28 sec)

Uploaded on Dec 31, 2015
Dr. Sam on International Waters made a P-Zero Rigger here is his effort:
Thread is here:
X430 prop cut down to 26mm best pass 38,436 rpm
1 oz fuel tank - Two pics are Dr. Sam's 1/2A rigger, followed by my finished rigger.

1/2A Engine break in time..
Outrigger - Picco .85cc /.0519ci / Profi Tuned Pipe 44,412 rpm (1 min 49 sec)

Published on Oct 2, 2016

Outrigger - Picco .85cc /.0519ci / Profi Tuned Pipe 44,412 rpm
Original designed outrigger hydro for Picco P-Zero
On the end of the 3rd tank I was able to lean it out enough
to get a idea of the top end still rich but on the pipe
should do about 46k no load once the needle is set.
30% nitro 18% castor Will post a maiden launch vid
perhaps next weekend.

1st Run a bit rich and too much prop but good run all the same:
I now have some suitable props to test next.

1st Run - Picco P-Zero Outrigger Hydro Profi Tuned Pipe (6 min 43 sec)

Published on Oct 9, 2016

1st Run - Picco P-Zero Outrigger Hydro Profi Tuned Pipe
.85cc / .05 ci / 1/2A car engine converted for boat use.
Very stable, needle valve set a bit rich for the first few
runs, need to lower the strut a bit, tracks very well.
Will do another vid after I tweak the setup.
Stock X427 / 20% castor 30% Nitro. Per Doppler
reading best pass 62.25 Kph or 38.68 mph.

2nd test day:

Picco P-Zero Full 2nd Vid Octura 1426 (modified) (7 min 6 sec)

Uploaded on Oct 30, 2016

Picco P-Zero .05 / .85cc engine - Cut Octura to 1426
RPM higher than the stock X427 Per Doppler reading for the
pass at 43 seconds on vid 36,902 rpm / 69.75 km/h - 43.34 mph
Med lift prop. 30% nitro / 20% castor.
Last edited by 1/2A Nut; Nov 21, 2016 at 04:52 AM.
Oct 16, 2016, 07:16 PM
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I have decieded to order another ARF I much prefer to design and
build but this one has shown great promise per Youtube vids and
I think will be a great fit for my Norvel .074

Mini Midget Mustang from Airborne models.

fastest midget mini mustang (1 min 3 sec)
Last edited by 1/2A Nut; Oct 17, 2016 at 10:19 AM.
Oct 17, 2016, 07:36 AM
Registered User
Really cool stuff, I enjoyed reading this thread and watching the videos!
Oct 17, 2016, 12:57 PM
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Wow that thing is fast...Cool
Latest blog entry: In flight
Oct 17, 2016, 09:05 PM
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Thank you,

Yes it is a stoutly built ARF by the looks of it and I have seen multiple vids of
folks pushing it to the hilt one has 4S going 189mph wow!!

Plus shipping to the door / Order amount: $90.98
Oct 19, 2016, 10:34 AM
Registered User
Originally Posted by Amp Abuser
Thank you,

Yes it is a stoutly built ARF by the looks of it and I have seen multiple vids of
folks pushing it to the hilt one has 4S going 189mph wow!!

Plus shipping to the door / Order amount: $90.98
At 27" wingspan an .061 would probably be plenty of power for sport flying.

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