Prodesign F18 90mm EDF

Realistic cockpit with instrument dashboard.

Prodesign fiberglass F18 with fixed landing gears. Very scale and nice design and built.

The intake is smooth and the decal is superb.

Will maiden her after upgrade with the ChangeSun electronic retract and shock absorbing strut.

75A 6s ESC with BEC

LM2596 - spec 40V to 5V, 3A switching BEC . Regret that the IR2101S pulse driver has max Vcc of 25V only, otherwise 7s can be used.

FDD 8896 FET x 6 , spec: 30V, 35A(max 95A each!) ; tota 35Ax3= 105A

Rebrand by many seller.

Starmax 90mm EDF

GI Joe : " Request permission to take off"

Stock landing gear length reduced by 2cm. No more problem with retracting gear.

Power ~ 1,100W at 6s 50A. Speed ~ 140kph only. With exit nozzle diameter reduced.

Plan to use 7s to gain more speed.

X-flight twin 70mm EDF Rafale

Very nice looking rafale with modified single 70mm EDF. Hoffman Magnetic at 4s x 70A ( limit of my lipo) ~ 1,000W. Certainly, at 1,400W it can fly even more ballistic!

My DIY is simple to make and cheap. What you need is

1) 3mm collars x 2

2) M3 screw and washer

3) A rectangular piece of fiber glass.

4) rubber band or propeller O-ring

The tension is set to ~2-2.5G . My rafale weights 1.4kg and the tension is set to ~ 3kg. The landing gear is all intact , even with hard landings.

L39 with front gear light

Installed a high power LED. The result is superb!

A DIY 3.7V regulator is used, with 700mA current drawn.

Will add red and green LED on th wings soon.

KDS flymentor 3D

The CCD unit.

3 axis gyro.

Will be installed in my new VTOL.

Solar panel lipo charger

The nice looking specification:
5.5V @ 500mA
Autocut overcharge/discharge of 2200mAh single cell lipo.

The unit can be charged also with a 5V source from a USB (some computer cannot deliver sufficient power)

Open the unit and found the stock lipo inside was crappy, and likely to be a used lipo . Testing and found the lipo only hold 10 % of the original capacity, and only hold voltage ~4.0V (should be 4.2V) with a lipo charger.

Reinstall with some better quality lipo and upgraded to 4400mAh.

BF109Z

Twin 109 with wingspan 1.2m. Setting : CC/CW 7030 prop. Slightly underpower with total current ~20A @3s.
The Emax motor has QC problem as you can hardly get any same kv motor, despite the label is the same. My first pair was found to have significant different current drawn (12A vs 22A). End up by purchasing another Emax. Lucky enough the kv is now matched with current drawn 12A vs 10A.

The C.G. with 2200mAh 3s Lipo can only be met by installing the BL outside the motor mount. The stock landing gear is quite soft. Will soon install retractable gear soon. It looks extremely scale in the sky. Since it is slight underpower with a low kv BL (1000kv),>

Flying character is quite different from other WWII fighter. In strong crosswind laning, the rudder can help very much as the aileron is not too sensitive, as the center of mass is far from center.

Freewing 3900kv EDF inrunner death

Freewing F35 stock 3900kv motor suddenly stopped in air. Luckily the plane landed safely. The ESC did not smell and likely the motor is burnt. Infra-red temp. measured >110 deg Cel.

The motor was found seized and postmortum was undertaken. Opening the can and the wires coating was found melted and seized the magnet. Distal third of the magnet is partially demagnetized (where the heat sink does not go that far).

Lesson to learn: Let the motor cool down before another flight! Especailly if the inrunner is aging.

Comparing high power EDF Brushless

Lt to Rt: 64mm EDF 4800kv SAPAC, 70mm EDF 3200kv 2842 SAPAC, 64mm EDF 3800kv Freewing.

The freewing has longer stator and thinner plate (0.18mm?). Their magnet seems to come from the same source and strength. Interesting, the SAPAC has lots of cogging.

Dynamically balanced?

2842 - Inside as well?

Rewind JustgoFly 500T Brushless

My JGF 500T (2000kv) has been a very powerful motor of high torque and low temp. After years of abuse, it died with core/stator melt down and burnt my cc35.
The stator is completely rewind with 14 strands 0.23mm in 5T.

Small amount of epoxy is used to hold the wires in place. Tested with 6x4e at 4s , current ~35A. rpm....forgot....Not bad.

The stock neodym magnets are still very strong !

One comment is the shaft is not replaceable. Mine got bent on a few occasions after crash, and needed to be straightened with some skill.....

BF109Z Zwilling Germany

This Twin 109 has never flied during WWII.

Building in progress....

TWM Voodoo P51 with retracble gear

Pre-installed retractable gear.
The pattern is nice looking. The only comment is the leading edge of the wing is not manufactured with balsa to make it smooth enough. The ridge of the spar is obvious here.

The battery tray allow easy access for battery change. The old version(not Voodoo) P51 does not have this latch/ battery compartment access ,and have to detach the wing after each flight.

Very light weight. Very manoeverable/ predictable and easy to built. Cheaper than foamy as well!

Repairing and Upgrading Phoenix CC35 ESC to 45A

2 FETs burnt in the front and 1 FET at the back.

A new FET is soldered to the back. Spare spaces available to upgrade to cc45.

My CC35 has served me many years as a reliable ESC. The soft start and high current cut programme has been working perfectly. The only downside is the onboard BEC is too weak and on 4s, you can barely plug in 2 mini servos, even so the BEC gets very hot.

Recently my JGF 500T (at 4s@40A) meltdown the stator core after I continuous fly my F16 at over 170kph. The high current surge burnt 3 FET (IRF 7832) on the CC35 ESC board.
Most of the time FET will burnt in a closed circuit with the In/Out pins shorted. Sometimes the single Gate pin will short as well.

I try to fix it , tools needed:
1) replace with some cheap IRF 7832 (cost~HKD $3 only)
2) 100W solder gun, best with temp. control., or blow torch soldering
3) Desoldering wire ( To clean any excess solder left on the board
4) Ohmmeter- to check for short circuit.


1) Remove all burnt FETs, usually complete row of a single polarity is burnt.
DO NOT BRUTE FORCE BY PRYING IT, OR USE TOO HIGH TEMP SOLDERING GUN TO TAKE IT OUT.
I use metal cutter to shear away the top of the FET, then carefully remove the pin with soldering gun. Clean any excessive solder with desoldering wire.
2) Check for short circuit or continuity of the board. Input -- Output - Gate
3) Apply flux on the new FET, to ensure a true soldering point.
4) Apply some glue to the back of the FET to stick it into correct place. (or anyway U can think of)
5) Press lightly on the FET (with a forcep) and apply solder. Be careful to limit the soldering time less than 2 seconds.
6) I test the ESC with a motor after soldering of each FET.
7) Finally I add another 6 FET to Upgrade it to 45A!

Photofast CR 5400 microSD-MS Duo Pro adapter

ATTO test, using Kinston 8G micro SDHC Class 4
Using Micro SD adapter--USB adapter- 20M R, 13M W
Photofast MS adapter -- USB adapter - 9.5M R, 9M W
SanDisk 4G MS Pro Duo-- USB adapter - 16M R, 6M W
Transcend Class 6 SDHC --USB adapter - 38M R, 38M W

Photofast adapter has higher write speed thatn SanDisk 4G, but almost 50% decrease in read speed.