My Recent Scale Heli Project...

[JYZoom]

Video

[hagenuk]

Wow.....very nice and stable

[Adrianli]

My contribution

Flying pics too dark to post. So just some close up pics.

[Super-Hornet]

Thanks JYHeli and Adrianli for the photo and video.

I found the original horizontal stabilizer liau! I thought I lost it but manage to dug out from my scale heli box.

The original horizontal weight about 49grams. With that weight a the rear end of the scale boom, it is going to make Center of Gravity way out.

So, I decided to build a similar one using balsa wood. It is sandwich of 2 thin sheet of balsa wood (sandwich with grain/line perpendicular each other). Since it is balsa wood, it is easily dented or break so I re-enforce it with thin layer metal epoxy. Haven't complete yet.

Here are the pictures.

SH

[MicroHeli-Nut]

Is the video taken in Yishun Ave 1? Near the Ring Road? It's near my workplace if it's there. Next time you fly this, please contact me! I can share your awesome work with my students and try to inspire them to become DIY builders!

Congrats on the successful build!

[Adrianli]

Video of the Pavehawk flying today. With "fuel tank release mechanism".

http://www.youtube.com/watch?v=tAWLfEFkrGQ&feature=mfu_in_order&list=UL

[kennethw]

Very nice ... making my hands itchy to go build and fly ... but no time and RC things here are so expensive.

[Super-Hornet]

Last Sunday, while I tried out more powerful battery (6S1P, 4000mAH), while heli already taking off, I tried to do a punch up to see what is the lifting power from the new batteries. While doing so, the main gear and the tail gear get "eaten" up. This force me to quickly land it. Lucky no damage to the fuselage.
Also lucky it is only the main gear that get damage. No damage on the torque tube and whatever gearing alone the torque tube as well.

This "eaten" up main gear, got me thinking. Here are the possible theory I suspect why the main gear (and the tail gear) got eaten up:

Theory #1
The main gear, after some time, the material got weaken and easily broken off.

Theory #2 (which I suspect more likely)
Friction exists between main gear and the motor pinion. When the heli is flown on normal (stock) configuration, the main gear is easily push to spin by the motor pinion due to lot LESS loading from the main blades (2 blades) and from the weight of the heli (lighter, main blades do not required to go higher pitch in order to take off).


When heli is used in the scale...and especially heli (in this case, Mini Titan) need to drive 4 blades of main and tail blades.. Further more, the main blades are a 370mm long. Couple to heavy weight from fuselage, the friction is much much higher at the main gear to motor pinion. The higher friction causes the main gear to heat up and weaken. Thus, causing the teeth of the main gear to break off.

To fix this problem, is to reduce the friction on the main gear. So, I going to apply some grease (Super-Lube) onto the main gear (and the tail gear as well). This should be able to fix the problem. I have to wait till this coming Sunday to test it out.

Friction on the gearing system that causes the gear to wear out is happen on tail gearbox before during development of this heli (see this thread, previous post at post #25, http://www.daddyhobby.com/forum/show...1&postcount=25). By applying grease onto it, it solve the problem. During replacement of the damage main gear, I visually check all the tail gearing systems (which I did put grease), and all those gearing are in good condition.

With that, my recommendation (especially on scale heli), is to apply some lubricant onto your scale heli gearing system.

SH