[Sparkfarmer]

I recently received all the components I needed to complete my Venture 50 kit(Main blades, receiver). I'm almost done my final setup, and nowhere in the manual does it specify a head speed. I only ask because I remember reading on a few threads some members paying strict importance to this.

Is head speed only a concern for hard core 3D'ers?

If I needed to, how do you set it up? With a governor or a rev limiter? How do you measure? Basic optical tach?

Cheers!

[824TSV]

I'm not specifically familiar with your heli, but I'm assuming it's a .50 size. I was taught/ told that on larger helicopters, .30 and larger, never to exceed 2000 rpm with a plastic head, or if the main hub is metal and the blade grips are plastic. If the head is metal, than I suppose you could exceed that by a couple of hundred rpm, but I wouldn't go much past 2000rpm myself. You can use an optical tach to check blade rpm, or if your using a ESC like a Castle Ice unit, you can check several different parameters including engine rpm and ESC temp, voltage, etc, using the Castle link downloaded onto your PC. Any build manual that I've looked at has suggested pitch and throttle curves along with recommended motor pinions. That would be a good start, because the manufacturer has calculated the head speed given various combinations. I have a couple of larger heli's and they seem to fly very well with the head speed around 1900-2000 rpm. Have a look at www.drhc.rchomepage.com/calc.htm for a very good head speed calculator.

[hardcore]

Based on the manual, you have a gear ratio of 9.78:1

This would mean a headspeed right around 1750, at an engine speed of 17000. You could push to the upper envelope of the 50sx-h and get 2000, but i'd shoot for around 1800 on the Venture.....

An optical tach works, as does a gov/rev limiter. The optical (presuming good batteries) will let you know that the gov/rev limiter is set correctly



HC

[Sparkfarmer]

Originally Posted by hardcore

Based on the manual, you have a gear ratio of 9.78:1

This would mean a headspeed right around 1750, at an engine speed of 17000. You could push to the upper envelope of the 50sx-h and get 2000, but i'd shoot for around 1800 on the Venture.....

An optical tach works, as does a gov/rev limiter. The optical (presuming good batteries) will let you know that the gov/rev limiter is set correctly



HC

Ahhhhhh..... that makes sense. Thanks!

[Phil Noel]

A 9.78/1 gear ratio is high for a 50 (even for a modern 30). Most 50's today run a gear ratio of 8.7 to 1 or in that range.

The higher the head speed, the faster the cyclic and collective response.

We set up helis today for high head speeds for the fater response we want for the more extreme 3D.

For the more sedate flying as in training, sport aerobatics and scale, you may well consider setting for lower head speeds in around 1600. This will make the heli much easier to handle, and result in longer lasting heli components and engine.