tail control "mushy" MD 500 aling 500 with 900 KV motor

[marke]

Just flew my MD500 for the first time and the tail is very soft -holds but is struggling..i installed the Scorpion 900 kv motor to reduce the head speed of the 4 bladed head--but no I might have a tail rpm issue where its to low.

any suggestions?

I don't know if I can get speed up gear set for the tail

thank you

[Trooper7]

I see the Align 500 has both a 36T and a 31T front tail drive option. The 31T will give slightly more RPM on the tail - though I couldn't tell for sure which autorotation gear would go with it in my quick search. I know with my 600 you had to match up the set.

So there's that option and/or longer blades.

Both these ideas assume you have the tail gain set up correctly

Cheers

[BlackTitanium]

Three things you must do, for a 500 size scale, to fly with a multi blade rotor head.

1. Use the 31T Tail Gear/145T Autorotation Drive Gear, for the higher tail gear ratio.

2. Use 600 size tail rotor blades.

3. With the gear ratio and tail rotor blade mods, lower the main rotor pitch, until you find the sweet spot.
Sweet spot = Full throttle climb out without blowing out the tail.


H50G003XX - M0.6 Torque Tube Front Drive Gear Set/31T
H50019AA - 145T M0.6 Autorotation Tail Drive Gear set-Black

[marke]

This is perfect thank you

[marke]

Just checked my gears and the front gear is 31 and antirotation is 145 t. Also the 600 tail blades will hit the ground. Might have to extend the vertical fin to allow more blade clearance. So I think the tail speed is as fast as it can go

[Bm421]

I just ordered a set of 80mm and 85mm zeal green tails both will fit with no mods. 85 seem a bit scetchy. I'm having the same problem.

[BlackTitanium]

Notice that my Little Bird has lowered skids, and the 600 size tail rotor blades have plenty of ground clearance.

[ame="https://youtu.be/XyRxUDsRPT0"]TH-6B Cayuse & AH-6J Little Bird: RC Helicopters - YouTube[/ame]

[Keyrigger]

When you are building an MD500 of any size with a five blade head and two blade tail, you need tail speed along with blade size to keep the tail under control. With my TOW Defender, I had a 4.5:1 ratio tail gearing and that, based on a 1575 rpm main rotor speed, gave me a tail speed of 7087rpm. In a perfect world, the ideal range for a tail rotor for optimum performance with a two blade head, is between 8000 and 9000rpm. I'm not far off that but it is with a five blade head, so I am disadvantaged in the power department a bit. I ended up getting my ideal balance using 105mm tail blades rather than the shorter 95mm ones that I had told myself were the "right ones" to have on it. If you are below 6500rpm, it may be very difficult to get that ratio changed to speed up the tail if you are using the torque tube system. It might be possible to find a smaller tail shaft pulley, which will increase your tail rotor rpm. A larger pulley at the main gear will have the same result. Good luck.

Don

[allegro16]

I have a BO105 500 size with Align 4 bladed head, running 1,750 RPM. With a 90mm tail blade, the tail holds fine, no problems at all.

Go with 90-95mm tail blades, or alternatively semi symmetrical tail blades (Spin/Helitec)