Re: seeking some F1D tips?
Tim, Fred and Martin: I apreciate very much your help.
I will first reply Fred, because he is asking some important
details that I have missed to post:
1) Are you getting to the top of the site?
Yes, but giving a full load, only touching one or two times.
In a 30 meters ceiling I will be in problems to reach the top.
2) Do you use up all of the turns?
Yes, almost all
3) If not how many turns are left?
Always less than 10%, usually 5% left (50 out of 1100)
4)What is your average rpm?
Arround 48 RPM
5) What is your cruising rpm?
Not sure about this, I will check on next flights.
6)What batch and size is your rubber?
Tan II 5/99, average 1.35mm x 210mm (0.053" x 8.26")
7)What is your prop pitch and diameter?
Propeller is 19" x 30", S. Brown design.
8)What does your plane weigh?
Depending on several configurations (changing wings,
stab, etc) the weight is between 1250mg to 1300mg in
the way it keeps stiff.
> You should be able to get more turns and torque out of the
> motors, as Tim said 9.5" of even lesser batches motor should
> give up to 50% or more turns than you stated, and .45 to 5
> in oz of torque should be attainable. Even supersport should
> take more turns
Yes, I can add some more turns (an more torque), but not much
more because I'm using a bigger cross section.
My model can't handle 0.45 in-oz!! It will be destroyed :)
Do you launch with 0.45 ~ 0.50 in-oz??
>unless you are using a large cross section motor.
You are right
> Any motor with a broken in length of less than 9" is
> pretty large cross section and if you need motors that big
> you might have to make some changes to your prop and or
> model trim.
> Fred Tellier
Again you are right, but what are the tests I have to do
to determine if I have to build a new model, less draggy
or start working in a propeller?
Now Tim:
> 1. Check your spar deflection- Your spars need to be pretty
> strong as if they are too soft, they will deflect too much
> causing the plane to climb a lot less than it really can. If
> you are already hitting the ceiling anyway, then soft spars
> may actually help a little. On indoorduration.com theres a
> whole article about F1D type props by Steve Brown.
Do you mean the prop spars deflection? Or wing spars? Any
case i think they are ok, both spars (prop and wings) are
pretty strong.
> 2. Rubber- I think its one of the most important aspects. If
> you don't have the super rubber (5/99, 8/93, etc.) then the
> times over 30 min can be difficult to achieve.
Rubber seems not be the problem since I have some good 99 and 93
> You said you were only getting around 1000 turns at .35 in/oz.?
> What size rubber are you using and what batch?
Sorry, thats because my poor english.. I mean with those
numbers the launch turns and torque. Im using a big section
and model can handle up to .35 in-oz. Of course I can wind
more turns and higer torque in a stooge , but not for my
model.
> At Kibbie Dome last year, 5/99 .049-.050 x 9.4"-9.5" was
> getting about 1600-1700 turns at a max torque of about
> .45-.47 in/oz.. The good stuff has a huge difference.
Wow, well I can put 1600 turns in a .049- 9.5", then back
turns to reduce torque, but my model will not climb and it
will land with lots of turns.
> 3. Check your downthrust (especially during launch) and your
> thrust line. If you have too much, the plane won't go
> anywhere. Typically, having no downthrust without the stress
> of the rubber is pretty good. If the plane stalls on launch,
> you can adjust the tension of the bracing wire so that the
> rubber tension makes the motorstick bow a little- adding
> downthrust.
This is not the problem, at least with the torque im using.
It clims with a good angle, not stalls not dive. Anyway is
an excellent tip!
> There's a lot more things to look for when flying F1D or any
> other class of planes, but these steps may help to increase
> your time! Hope this helps and ask questions if you have
> any.
> Tim Chang
Thanks Tim, well sure it will help, and please keep going the
good tips. Its very hard to learn from a book or via email.
Here, in Argentina, there are too few people doing F1D and
we are all in a nebulose.
It will be priceless to see you guys flying in a world or
national contest. For now, i keep bothering you with
questions. :)
Now Martin:
> How many models have you made? Model making is like anything
> else,with practice you get better at it. Did you struggle to
> get to weight? Are you close to weight? You quickly learn
> that weight isn't the most important thing. The model has to
> be strong and stiff enough. If you struggled to get to
> weight you might have the weight in the wrong places.
Six, but from all thos I saved 3 models, the stiffer was the
selection criteria, then weight, almost there (~5% overweight)
> You say you have problems getting the turns in. Do you
> stretch wind? Do you use lube? The better flyers know how
> to pack in the turns. Like building, it really pays to
> practice winding, or at least do a lot of winding.
Martin, I explained above why the low turns. Yes, I strech wind.
Lube is 5000 cts silicone. And you are right, probably I need to
pack better the turns and practice winding.
>Don't be discouraged.
Yes, still fighting :)
> The guys with the great times have been doing this for a
> while now, or have mentors with a lot of experience. Even
> for the experienced guys the times didn't start out nearly
> as high as they have gone. Folks had to learn what works
> with the "new" rules. We benefit from their hard work, but
> there is a lot that goes into a sucessful indoor model.
> Good luck.
> Marty Sasaki
Sure, but how to do the step from 20 minutes to 30 minutes?
Will be incredably to have a mentor, but we are 8000 miles
away. If any of you travel to argentina, we have exelent
"Asado" to pay with :)
All above said, hope you can helpme with this 2
two questions that are breaking my head:
1) How do I know if I have to focus my work on propellers or trying to
reduce drag by triming?
2) What will be the "terical" or "ideal" propeller size (S. brown
design) to be used with a 0.49-9.5" 5/99 rubber?
Regards!
Ignacio
Received on Wed Mar 14 2007 - 09:45:20 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:45 CET