I added the pictures to my photos on the indoor free flight group page. Hope these help you.
________________________________
From: Bruce McCrory <hbm55_at_comcast.net>
To: Indoor_Construction_at_yahoogroups.com
Sent: Saturday, 20 December, 2008 4:48:07 PM
Subject: [Indoor_Construction] Re: Optimizing a ministick
I don't see images, but the Utube video was enlightening. Prop looked
good, and your comments mean there's a cheetah in the tank.
Definitely wound to "no touch" torque. You want a torque meter, to
record the no-touch force; then wind to 90% turns and back off to
the "no touch" power. It will extend the flight time, giving you more
turns, longer cruise torque.
.039" (1mm) is going to be too powerful for the weight adjusted
model. It's a good size for A6, however.
Others on the list might see more than me. My thoughts:
The wash can be reduced. I don't use any, relying on the MS to twist
it in during launch torque and climb. Fixed wash equals cruise
hassles and drag. This is a good opportunity to shave down the mass
of the motor stick. Remove smidges of incidence - the bobbing can be
that, or the high wash angles.
MS should be about .08 - .10 grams. Mine are .07(-) and hard wood,
7# - 8#. Thinner sections twist better. Put about 5-7 degrees tilt in
the stab - drop right side. Straighten the wing spars - no wash. Get
some .023"-.027" rubber, same 11" length and wind it to 90% of break
turns to test full model duration (and endurance). .027" is
competition size for your lower ceiling. Start grinding down the MS.
When the weight gets down close and the wound rubber doesn't break
the stick, but the stab levels out with the wing spar line, you are
close. The MS will automatically twist wash-in into the left wing
panel. It's ready for fine tuning in the field house.
If you can beat on the ceiling, test at full torque. A half, or third
motor might help at this stage. The idea is to file down more wood
section on the sides near the front wing post and increase the launch
wash slightly. I've never done anything with the stick behind the
posts but to reduce weight. MHO, the short moments counteract any
advantage to moving the thrust line, like in EZB. Mini-stick seems to
like steady, straight booms.
This is fun homework.
Bruce in Seattle
--- In Indoor_Construction_at_yahoogroups.com, matthew taudevin
<mattnsim_at_...> wrote:
>
> thanks bruce for the info.
>
> My props have helical twist.
>
> rubber is 11" loop of 1mm square and weighs .5grams
>
> The model weighs .6grams without rubber so all up weight with
existing motor is 1.1grams. A little heavy but it is my first
ministick. i may be able to take some weight off with some light
sanding of the fuselage.
>
> ceiling is normal pointed variety and is about 20 feet high. here
is video you will see the obstructions that I mean.
> http://www.youtube.com/watch?v=-wzy7v0funk
>
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Received on Sat Dec 20 2008 - 02:58:36 CET