Rotor blades for .60?

[creightoncarr]

I recently acquired a Raptor 60 which I will eventually convert to a 90. For now, however, I'm running the 60 stock with an OS .61. I had a set of TT 680 carbon graphite mains which I've been using but they seem to bog the head pretty easily. I'd like to replace the mains with Radix or V-Blades but before I do I would like to know if there is a concensus as to length for optimum performance. Would I be better offer running 620's or 660's over the 680's?

[DebianDog]

I run 690's but you can't run 12 degrees of pitch without bog. At least I have not figured it out.

I would not mind trying some 660's. I "think" 620s would be too small as she is a bit of a pig.

[creightoncarr]

Thanks - I think you meant you can't run 12 degrees of pitch? What are running for gearing and what HS are you getting? I'm running the 93T main with the 12T pinion. I haven't had a chance to tach it yet, but I think I'm getting about 1900-1950, but pitches of greater than +/- 9-10 degrees it drops significantly. 12 degrees of pitch for more than a second seems a big no-no right now. Would the OS .70 make a significant difference in performance?

[DebianDog]

Yes (corrected) can't. I am running the standard gear ratio and a YS motor. I have been told it is the wrong ratio but have not really looked into it yet.. quite honestly.

The are having a test and tune in a few week in Maryland and I was going to have some pros looking at it. I am trying to 1750 and 1850 on the governor.

Many folks do say the 70 livens it up but I personally would just go to a 90 and be done with it.

[flyinfool]

12° of pitch is hard on a raptor 90 with 680 blades.
Back when I had a YS61 I never could get more than 9.5° @ 1800 HS, reliably with 680 blades.
Remember that the Raptor head is one of the bigger ones out there, 680 blades on a Raptor will give close to the same disc area as 710's on a Fury.

[creightoncarr]

Well, after all of that, I've gone against what I originally was thinking and have put on a set of V-Blade 690's. I still haven't had a chance to tach it, but I think I'm getting about 1900rpm in hover at about 4-5 degrees of pitch and 95% throttle. My pitch curves are still ~ -10 to 12 degrees in idle ups and my cyclic throws are 8 degrees in all directions. My collective management is no Szabo-like, but it's pretty decent. With my current setup I'm scared to do more than one or two stationary flips in succession because the head seems to bog so much I'm worried about stalling. I'm going to play around with the pitch curves some this weekend and try +/- 9 degrees. On my flips though I'm only going back and forth between +/- 5-6 degrees so I can see decreasing the pitch range really having much of an effect. If this about what I should expect from the .61? If there anything I can do that might liven it up? I'm going to convert to the 90 in the not too distant future, but I would like to find a way to enjoy flying it in the meantime.

[flyinfool]

With 8° cyclic you may be using to much there also. Try backing the cyclic down a little and maybe go to lighter paddles to get the response back up.

The 690s will be a load for the 61 to swing AZ ran the 690's on the 90 engines.