Other Source For Roban Apache 700 Parts

[tip22v]

Sounds higher than 1400 to me, especially give how aggressively he is flying it. I will try to post a video of various optically tached head speeds this week. After reviewing my logs from my hovering yesterday I reallzed my headspeed was actually 1900, not 1250 as I previous posted. The heli in this video sounds like mine from yesterday. Today, I'm going to focus on trying to get the headspeed down to 1400ish and see how she flies. I went through the Roban manual again last night and no where does it say or recommend a headspeed, I think that is a deliberate omission on the Roban side. Has anyone seen any official recommendation on headspeed from Roban?

[sfcfury]

Well obviously it's a subjective thing to try and judge by sound, but I would say the Apache in the Roban video is in the ballpark of 1200-1300ish. I don't have a 4 blade to compare too (yet... have a EC-135 waiting on me lol).
Here's a video of my Cobra. When I take off I am 1250~rpm; around the 1:32 mark I switch to Idle Up 2 which is 1350~. I get a 'little aggressive'... All things considered cool foggy morning, 750mm blades x2... The 1350 Cobra to the Apache video sound similar to me.

[PawPaw]

Here’s what I have recently tried and believe it to be a better way to eliminate guessing on headspeed selection. The goal is to have a hovering blade pitch of around 5-6 degrees. So, make a note of your stick position at stable hover, then measure the actual blade pitch at that stick position on the bench. If it measures less than 5 degrees then headspeed is too fast. Idea here is to reduce friction and gear wear as much as possible. If it measures more than 6 degrees, and you are comfortable with the performance…roll with it. If not, bump the HS up to attain the 5 degrees. Just my 2 cents!

[tip22v]

Here is the Optical Tach that I use to check headspeed. I've had this about 10 years and don't remember where I bought it. I especially like this because you can tach the head from a distance. It has a little spinning wheel in the view window on the top left. All you have to do is adjust the speed of the wheel to make the head look like it's stopped, then read the display to see your head speed.

[tip22v]

Here’s what I have recently tried and believe it to be a better way to eliminate guessing on headspeed selection. The goal is to have a hovering blade pitch of around 5-6 degrees. So, make a note of your stick position at stable hover, then measure the actual blade pitch at that stick position on the bench. If it measures less than 5 degrees then headspeed is too fast. Idea here is to reduce friction and gear wear as much as possible. If it measures more than 6 degrees, and you are comfortable with the performance…roll with it. If not, bump the HS up to attain the 5 degrees. Just my 2 cents!

That is an excellent method! I like it because it keeps one from fretting over the headspeed. In the end, we all are going to need a certain headspeed to produce adequate lift to fly, what ever that will be will be.

[PawPaw]

My opto tach is due to arrive today and I plan to see what all the hoopla is about. This entire forum is a huge conspiracy to defund PawPaw’s meager retirement savings and I’m on to y’all now. I absolutely will not order another single thing just ‘cause y’all make me think I can’t live without it. Except sfcfury’s awesome sound system.

[DCORSAIR]

My opto tach is due to arrive today and I plan to see what all the hoopla is about. This entire forum is a huge conspiracy to defund PawPaw’s meager retirement savings and I’m on to y’all now. I absolutely will not order another single thing just ‘cause y’all make me think I can’t live without it. Except sfcfury’s awesome sound system.

...I ordered me a Tach as well, I see all these different numbers people are running and I realize my way by ear may not be accurate after 30+ yrs, so my goal is to learn the math better and figure it out, all this time I thought I had a gift or something, nope just dumb...

[sfcfury]

Hey I just suggested it … I needed something to try to confirm it was doing what I thought it was doing b/c I don’t run telemetry. I will say take some averages with the lil opto tach- I know certain light conditions will affect the reading…

[sfcfury]

Hey I just suggested it … I needed something to try to confirm it was doing what I thought it was doing b/c I don’t run telemetry. I will say take some averages with the lil opto tach- I know certain light conditions will affect the reading…

[tip22v]

Hey I just suggested it … I needed something to try to confirm it was doing what I thought it was doing b/c I don’t run telemetry. I will say take some averages with the lil opto tach- I know certain light conditions will affect the reading…

Are you taching the tail rotor then dividing by 4.7, or are you holding that tach over the main blades?

[DCORSAIR]

Hey I just suggested it … I needed something to try to confirm it was doing what I thought it was doing b/c I don’t run telemetry. I will say take some averages with the lil opto tach- I know certain light conditions will affect the reading…

Paw Paw is right, you make us spend money for some reason,. I sent you a message back, all fun aside I really do appreciate all the help I get and read what you guys do and use, now we just got to get tip22v up and flying his Apache....oh wait, who started this thread anyway?...

[PawPaw]

🤣

[PawPaw]

Doesn’t sound like telemetry is a perfect standard either. I have doubts with a 1900 HS telemetry result assuming gear ratio is set to 13.8, pole divider is at 5, and governor set point is entered at 1250. I am unfamiliar with Jeti (or any telemetry) so does the telemetry require or allow variable changes in a menu? I’m asking because you posted that in the Apache video it sounded fast to you. 1900 rpm on that 4 blade/700mm would sound absolutely insane by comparison! How do your motor and ESC temps feel like after a hover session?

[sfcfury]

Are you taching the tail rotor then dividing by 4.7, or are you holding that tach over the main blades?

I hold the tach over the main blades.

[tip22v]

Doesn’t sound like telemetry is a perfect standard either. I have doubts with a 1900 HS telemetry result assuming gear ratio is set to 13.8, pole divider is at 5, and governor set point is entered at 1250. I am unfamiliar with Jeti (or any telemetry) so does the telemetry require or allow variable changes in a menu? I’m asking because you posted that in the Apache video it sounded fast to you. 1900 rpm on that 4 blade/700mm would sound absolutely insane by comparison! How do your motor and ESC temps feel like after a hover session?

You were right to suspect the 1900 RPM. I rechecked everything last night, the 1900 was not correct. When I set the Pulse per Revolution to 5 (per your recommendation and the IKON instructions) the Optical Tach reading and the Jeti Telemetry are very close (+-30). Based on my calculations 1900 is not even mathematically possible with a gear ratio of 13.8 and a 500kv motor. I'm not sure how I thought the optical tach was reading 1900 when I came up with that number:).

[tip22v]

I broke one of the little air pressure sensors when mounting the blades at the field yesterday. MotionRC has the parts but they want $117 for a couple of small pieces of plastic. Anyone know of an STL file for these little antennas/pressure sensors? In the meantime, here is a video I compiled from flights this past weekend. I apologize in advance for the obnoxious music:).

https://www.youtube.com/watch?v=w76rIvgPNWQ

[PawPaw]

Very nice, tip! Impressive!

[sfcfury]

Looking great! So what head speed did you settle in on to fly with? I don't have any apache files... if you can't find someone on here to send you a STL file,
you can hit up TyG at www.tylergraymodels.com/... if he don't have it already, he should be able to draw it up, and he can print in resin for you as well.

[tip22v]

Looking great! So what head speed did you settle in on to fly with? I don't have any apache files... if you can't find someone on here to send you a STL file,
you can hit up TyG at www.tylergraymodels.com/... if he don't have it already, he should be able to draw it up, and he can print in resin for you as well.

I set the headspeed governor to 1250 RPM, verified it with my optical tach. It flies quite nicely at this headspeed, the tail feels very locked in with good authority.

[tip22v]

Very nice, tip! Impressive!

Thanks!