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Posted by precise_builder | Jul 24, 2019 @ 08:15 PM | 1,908 Views
This is my long term project in 1:16 scale for 3 x 70 mm EDFs in 4s configuration.

The model will be semi-composite, using Norbert Rauch foam-balsa-composite method, tail cone and nose cone will be composite, 3D printing parts are considered as well.

As of right now, the tail "cone" plug is ready for creating a mold, the nose is pending.

Engine nacelle and ducting molds are ready.

Tail S-duct is in progress. More pictures are on the way.

To be continued...
Posted by precise_builder | Jul 19, 2015 @ 10:25 AM | 1,948 Views
Hi folks,

I recently started my semi-composite Yak-40 project at 1:12 scale, that features molded fiberglass nose and balsa/depron/fiberglass fuselage and wings.

The Yak-40 will be powered by three 50-mm edf at 0.6 kg of thrust each.

At the initial stage of the project I decided to take advantage over the exciting composite technology as it provides excellent look, great stiffness and longevity of parts.

I will launch a thread in rc airliners as soon as more essential parts are ready.
Posted by precise_builder | Dec 30, 2013 @ 03:37 AM | 5,167 Views
Hi folks,

I would like to share my experience in assembling of 70 mm edf units capable of producing up to 4,5 lbs or 2 kg of thrust using 4S lipos. My choices are edf outrunners cyclone power cs480 2800 or 3300 kv and very popular 10, 12 change suns and 14 bladed XRP. I prefer hyperion 45C batteries, using 2600, 3300 and 5000 mAh to power my stuff.

The reason I decided to use 70 mm edfs is mostly because this size can be fit in most of the light edf jet planes, providing sufficient thrust and optimal scale of the airframe, keeping the whole project affordable.

No doubt 10 and 12 bladed change suns is the most reasonable choice, considering value, potential thrust and sound. The next question is the right motor. My first experiments with only 3S 1800mAh 20C battery at hand, 3300kv cyclone power and 12 bladed change sun peaked at 1300 g of thrust which I measured on a primitive but working test rig equipped with a digital pull scale (pics coming soon). That pull was already enough to keep my interest with cyclone power motors.

Next stage was familiar to everyone mess with balancing the fans, rotating them against the motor, rotating shaft against the axle, spinner against the fan, etc etc. Finally I managed to accumulate a bunch of decently balanced setups, although issues besides the balancing had come right away too. They were:

Issue #1 - Stator coils may be wired differently. A second cs480-2800kv in my collection, rotor balanced well, with also balanced...Continue Reading