[EMAIL PROTECTED] writes:
With your setup, how can you get 90 degree flap throw? It's a bitch for
me.....
You engineer types drive me nuts :-) However thank you for all that, you are
right on the leverage thing. Your question above is a perfect reason for
why I answered the thread... and wrote the article.
I ran into a nice guy who had a third hand molded Psycho. No one who owned
it, could get a straight launch or a great launch. Obviously that made no
sense.... and in general none of the owners liked its performance...and it
was all due to your above observation.
The servos were glued to the top skins of the wing, and the servos had longgg
arms to get that beloved 90. It had the original Volz MM's in the wings so
there should have been plenty of power to hold the flaps for launch, yet on
launch it was easy to see both flaps go up, or depending on the release angle
the left or right.
The new owner was perplexed and couldn't understand why the Volz didn't seem
to have the holding power, when on the bench you couldn't get one to move
when plugged in by itself. (but that's a different topic)
They asked me to take a look at the plane (since I actually listen to guys
like Sage, JW, DP when they talk about stuff like that :-).
The first thing I addressed was the wild launch. I had him set the preset
then launch and asked everyone to watch the flaps. Yep they were not holding
and the launch was exciting the wrong way.
Then with the plane on and in his hand, flaps down fully, I reached over and
lifted one flap easily almost all the way up! (obviously he needed a 5 cell
pack ...not.)
Then with the flaps up, I showed him that he had nearly 1/2" of slop (no
kidding!).
On examination of his mounting and linkage, it looked like there was a bunch
of 'slop' at the servo output shaft...but closer exam showed that the way the
servos were 'glued' in was allowing the upper skin to 'oil can' some.
But the big culprit was his servo arm connection and his surface connection.
It was in a four hole arm at the end at the servo and at the bottom of the
surface horn hole.
Simply by switching his servo arm hole to the second hole and the surface
horn to the top hole, virtually all of the 'slop' disappeared and I could no
longer overcome the servos by lifting the flap.
A bunch of Nose weight was pulled (that was someones fix for the wild
launching), and the plane was launched a bunch, straight and true. Next was
to move the tow hook back to where it belonged (another 'supposed' fix for
the wild launches) and suddently the previous owners were feeling kind of
bummed!
Oh yeah, what about getting 90 with that link set up? Do it with the radio.
Travel adjustment. Also with setting the servo arm leaning a notch toward
the flap. More importantly do what Ben Clerx convinced me of at Visalia...
don't bother with 90 flap. Less turned out to be more as in a more
predictable speed approach on the landings. Full flap never really
'hits-the-brake" like we hope for in those "Yeow! I'm coming in to hot!!!"
situations.
And thats about all I have to say about that :-)
Gordy
Dallas this week
