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Re: Climbing issues

Posted: January 19th, 2020, 6:35 pm
by Nano1llus10n
If retrimming still doesn't work, I recommend using thicker rubber of the same weight as previous motors, which will preserve CG and provide more power for your flight.

Re: Climbing issues

Posted: January 30th, 2020, 6:15 pm
by kpanda22
My plane isn't climbing at all, it does get 2 full, slow turns before touching the ground but it does not go higher than when I let go of it. Are there any obvious changes I should make to the plane that I have missed? (sorry for the vagueness)

Re: Climbing issues

Posted: January 30th, 2020, 8:17 pm
by coachchuckaahs
kpanda22 wrote: January 30th, 2020, 6:15 pm My plane isn't climbing at all, it does get 2 full, slow turns before touching the ground but it does not go higher than when I let go of it. Are there any obvious changes I should make to the plane that I have missed? (sorry for the vagueness)
You give very little information to go on to help you.

Best is to post a video. Also, list key parameters such as decalage, CG location (with rubber), Biplane or monoplane, what kit (if any), Tail moment if not a kit, mass without rubber, how you are winding (max torque, launch torque, and number of winds, rubber linear density in g/in, rubber mass, loop size). There are many other variables. but to understand your basic trim and power conditions, these parameters would be a start.

Coach Chuck

Re: Climbing issues

Posted: January 31st, 2020, 3:37 pm
by kpanda22
coachchuckaahs wrote: January 30th, 2020, 8:17 pm
kpanda22 wrote: January 30th, 2020, 6:15 pm My plane isn't climbing at all, it does get 2 full, slow turns before touching the ground but it does not go higher than when I let go of it. Are there any obvious changes I should make to the plane that I have missed? (sorry for the vagueness)
You give very little information to go on to help you.

Best is to post a video. Also, list key parameters such as decalage, CG location (with rubber), Biplane or monoplane, what kit (if any), Tail moment if not a kit, mass without rubber, how you are winding (max torque, launch torque, and number of winds, rubber linear density in g/in, rubber mass, loop size). There are many other variables. but to understand your basic trim and power conditions, these parameters would be a start.

Coach Chuck
Hi sorry about that, here is the link to it flying: https://youtu.be/kpZZrnCB_1U

It is a monoplane of the Freedom Flyers kit. Mass without the rubber is 8.1 g, rubber is 0.075" width and was 42" before looped. Center of gravity is 1.1" in front of the rear wing post, and the number of winds has been tested from 50-100 winds using a 15:1 winder (all with poor results, 100 winds having the best performance). The video is taken outside but it is flying the same indoors as it is out.

Re: Climbing issues

Posted: January 31st, 2020, 5:07 pm
by bjt4888
kpanda22 wrote: January 31st, 2020, 3:37 pm
coachchuckaahs wrote: January 30th, 2020, 8:17 pm
kpanda22 wrote: January 30th, 2020, 6:15 pm My plane isn't climbing at all, it does get 2 full, slow turns before touching the ground but it does not go higher than when I let go of it. Are there any obvious changes I should make to the plane that I have missed? (sorry for the vagueness)
You give very little information to go on to help you.

Best is to post a video. Also, list key parameters such as decalage, CG location (with rubber), Biplane or monoplane, what kit (if any), Tail moment if not a kit, mass without rubber, how you are winding (max torque, launch torque, and number of winds, rubber linear density in g/in, rubber mass, loop size). There are many other variables. but to understand your basic trim and power conditions, these parameters would be a start.

Coach Chuck
Hi sorry about that, here is the link to it flying: https://youtu.be/kpZZrnCB_1U

It is a monoplane of the Freedom Flyers kit. Mass without the rubber is 8.1 g, rubber is 0.075" width and was 42" before looped. Center of gravity is 1.1" in front of the rear wing post, and the number of winds has been tested from 50-100 winds using a 15:1 winder (all with poor results, 100 winds having the best performance). The video is taken outside but it is flying the same indoors as it is out.
A significant potential source of your climb issue is that your motor needs a lot more turns in it. A 21” loop of .075” rubber will take 2,600 turns (with proper torque measurement and backoff winding). Of course, it is best to measure the density of the rubber and not rely upon width measurements. You would be well served to read the previous posts in this thread to learn more about winding the motor.

Have fun and research, research, research (meaning: read, read, read). To achieve excellence requires study of state of the art.

Brian T

Re: Climbing issues

Posted: January 31st, 2020, 5:11 pm
by coachchuckaahs
I agree with coach Brian.

Your plane looks to be terribly under powered in the video. Attitude is about right, perhaps even a bit nose high. but there is no forward thrust. Wind considerably more, possibly go to thicker rubber, possibly adjust the pitch of your prop.

Coach Chuck

Re: Climbing issues

Posted: January 31st, 2020, 5:37 pm
by kpanda22
bjt4888 wrote: January 31st, 2020, 5:07 pm
A significant potential source of your climb issue is that your motor needs a lot more turns in it. A 21” loop of .075” rubber will take 2,600 turns (with proper torque measurement and backoff winding). Of course, it is best to measure the density of the rubber and not rely upon width measurements. You would be well served to read the previous posts in this thread to learn more about winding the motor.

Have fun and research, research, research (meaning: read, read, read). To achieve excellence requires study of state of the art.

Brian T
Okay, thank you! Just curious, how did you calculate the 2,600 turns?

Re: Climbing issues

Posted: January 31st, 2020, 5:48 pm
by bjt4888
Kpanda,

See earlier posts for the link to John Barker’s “turns formula”.

Brian T