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Punkin71
02-17-2009, 07:20 PM
to the people that started out with a blade 400 and have flown it for at least 6 months (or cx2 then moved up to the b400) what expo settings did you start out with and what are they now?

Slyster
02-17-2009, 07:31 PM
+10 for a few weeks.. then lowered by 1 each day I flew... you do want to get to INH (0) that's best! Some even go negative!

Punkin71
02-17-2009, 07:42 PM
so far I've worked my way down to 7% on cyclic and 10% on tail. I wish I had more room close to home to let her do what she really wants to do!

Wolfpackin
02-17-2009, 07:52 PM
I disagree with the need to get to zero Expo or INH.

Remember that Expo can be used to make the circular movement of the servo arm linear.

There's a great thread on the Trex forum explaining that expo is not necessarily just for beginners in that it turns the circular movement of the servo arm into linear motion translated to the linkages.

Here are some quotes from that thread:

By:TomRex

Quote:
I see this stuff about linear this and that, most if not any of you have seen or remember the old linear moment servos from the 70's, the ones with the eyelet on a long screw,now that was linear. The whole point of adding expo is to mimic a linear throw, you nay sayers think about your geometry before responding......

By: Gary JP4

Quote:
Like TomRex said above, expo can be used to make a circular servo, like we all use, mimic a linear servo. Since our servos output a circular motion and given that you are set up with mid stick in the middle of travel with the servo arm 90 degrees to the actuator rod there is more linear movement near the middle then at the ends (20 degrees from the middle gives more linear response then 20 degrees at the ends) in response to the same stick movement. Expo can smooth this out into a more linear response. So, without expo we don't get linear response on the servo

Here's a link to the whole thread.
http://www.helifreak.com/showthread.php?t=44882 (http://www.helifreak.com/showthread.php?t=44882)

BTW, I started with around 25% on cyclic and 10% on rudder.
I'm down to 15% cylic, 5% rudder and will probably keep it there.

Slyster
02-17-2009, 07:58 PM
Good points. Truth is one can get used to anything. If I went up to %15 is would feel very slow to me. I never used expo on the tail. Just experiment until you like how it feels I suppose.

Penguin
02-17-2009, 08:03 PM
I started out with 80 DR and 25 expo and left it there till flight 80 then quickly went to 100 and inh. I started using sim at flight 80 and I found I couldn't fly my real heli like the sim because of DR and expo.

Punkin71
02-17-2009, 08:07 PM
never really thought about it like that wolfpackin, but your post does make sense. but I think getting used to a more sensitve center stick can only help develop skills.

Wolfpackin
02-17-2009, 08:15 PM
Just experiment until you like how it feels I suppose.
+1

Blade~400~er
02-17-2009, 08:56 PM
to the people that started out with a blade 400 and have flown it for at least 6 months (or cx2 then moved up to the b400) what expo settings did you start out with and what are they now?


i got my cx2 in january of last year, then got a fixed pitch heli and flew that from march-june then got my b400 in early june and been flying primarily it since the end of the summer....

I turned my D/R settings on both elevator aileron down to 90% (this limits overall servo throw)

Then I added POSITIVE expo 30% elevator and 35% aileron( the expo curve does not begin to take a noticeable effect until above 25%)

Rudder remains unchanged

after doing that the heli became way more manageable,.....you may also want rueduce the amount of negative pitch you have in normal mode......this will keep you from slamming the heli into the gorund in the event you want to "chop stik" :thumbup:

Currently my D/R is 95% for both but still the same expo settings of 30 and 35......gotten used to the way the sticks respond at these setting and changing them I fear wouold throw my muscle memory to crap

Slyster
02-17-2009, 08:58 PM
And you fly great! Another vote for "when you like how it feels" I guess... so really there are no rules!

Blade~400~er
02-17-2009, 09:12 PM
And you fly great! Another vote for "when you like how it feels" I guess... so really there are no rules!


thanks sly.....i dont know if its "great"...lol...deff got it smoothed out though but now i need to start working on the exotic stuff and catch up to guys like you and sokal :)......if i could get a few calm days in a row i could really work on getting my stall turns perfected so when i go to pull the trigger on my first loop, the recovery will be second nature should the heli decide it dosnt want to pull through,....also been working on my "Split S" in the sim, also a form of recovery from the loop, split-s-ing out of a loop uses alot less altitude in a failed attempt but requires more co-ordination IMO.....kinda a user preference there i guess....

helidevil
02-17-2009, 09:32 PM
i had to re set everything at first, but im running about 20-30(i change it if its windy:YeaBaby:)

xspare
02-17-2009, 10:20 PM
The "RTF" B400 is my first heli. Initially I thought the tail was too fast so I tried expo, but I turned it off after one flight since even 25% couldn't make much difference with the limited stick motions that I was using while running through the RADD program. After this realization, I decided to use stock the tx curves and remain satisfied with them to this day.

I was never happy about the stock rudder throw binding the tail slider (at perhaps 2/3 stick) so I soon adjusted the tail servo to use the innermost hole on the tail servo horn. You really need to raise the tail servo towards the boom if you do this mod, and can likely increase your gyro gain to 77%.

I'm still using the stock gyro and tail servo and (using frame-by-frame video measurements) the heli still pirouettes at 120 rpm (2 revs per second). I don't suffer from any wag or kick on the tail.

By using the inner hole on the horn, and based on the concept that wolfpackin has related to us, I am operating with something akin to negative expo on the tail.

xspare
02-17-2009, 11:04 PM
t....also been working on my "Split S" in the sim, also a form of recovery from the loop, split-s-ing out of a loop uses alot less altitude in a failed attempt but requires more co-ordination IMO.....kinda a user preference there i guess....

I think you might have a misconception about the split-s:"A Split-S is a very useful positioning maneuver, since it turns you around and you drop a bit of altitude"
Do you mean you're bailing out at the top half of a botched inside loop (by rolling to level flight) and turning it into an immelman, or are you talking about turning it into a half cuban-eight by rolling out of inverted at 5/8ths of the inside loop and pulling back up into level flight?

If you think you're in deep doodoo as approaching 5/8ths, then I expect you're probably better off skipping the roll and transitioning to the outside loop by going negative on the collective, pushing the cyclic forward, and pulling negative g's.

http://en.wikipedia.org/wiki/Aerobatic_maneuver

mr2mkii
02-17-2009, 11:30 PM
While I started out on the mcx, then cx2, I found in each case I began with a good bit of expo (like +30%) and now have NEG expo on both. I've had the b400 now for nearly two months. I started out with 90% & +30% expo on everthing but 85% & +5%expo rudder. In a month it was down to 25% expo on the cyclic.

As soon as I removed the training skids, she was moving faster, and I felt I was making this huge and slow (due to movement distance) stick changes to keep up. Then I reduced down to 15%, bingo! I like having it react more with lesser movement now, and I feel more comfortable! I also bumped all the limits, except the rudder, up to 100% now as well.

Blade~400~er
02-17-2009, 11:31 PM
I think you might have a misconception about the split-s:
"A Split-S is a very useful positioning maneuver, since it turns you around and you drop a bit of altitude"
Do you mean you're bailing out at the top half of a botched inside loop (by rolling to level flight) and turning it into an immelman, or are you talking about turning it into a half cuban-eight by rolling out of inverted at 5/8ths of the inside loop and pulling back up into level flight?

If you think you're in deep doodoo as approaching 5/8ths, then I expect you're probably better off skipping the roll and transitioning to the outside loop by going negative on the collective, pushing the cyclic forward, and pulling negative g's.

http://en.wikipedia.org/wiki/Aerobatic_maneuver


i guess i had my slpit s and cuban 8 mixed up buu yea i meant bailing out at the top half of a inside loop (by rolling to level flight) and turning it into an immelman .....like i was telling sly ive got upright flight nailed dwon but ive yet to break that 90 degree barrier....and i wish i could show you with a vid but im simless.... currently awaiting my copy of pheonix......i kicked real flight to the curb today...

odam2k
02-18-2009, 09:46 AM
I started out witha Blade CP Pro, a very very twitchy little rascal. When I got my 400 a month later, I set my expo to -35% (Yes, thats NEGATIVE) I guess I got so used to the CP Pro that the 400 just felt way to mushy... Now, I've been flying the 400 for about 7 months, and I think I'm up to -10% now...