Helicopters C

Locked
Blonded
Member
Member
Posts: 16
Joined: March 12th, 2018, 1:01 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by Blonded »

Rêveur wrote:
vjindal wrote:https://youtu.be/nn-x44gB0oA

This is our helicopters journey this year.

Let me know if you have any questions!
Very very impressive. Did you guys find any modifications to the FFM kit to be helpful, or were you able to get a 3 minute time without modding the original plans?
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
User avatar
daydreamer0023
Member
Member
Posts: 198
Joined: January 29th, 2015, 5:44 pm
Division: Grad
Has thanked: 1 time
Been thanked: 1 time

Re: Helicopters C

Post by daydreamer0023 »

Blonded wrote:
Rêveur wrote:
vjindal wrote:https://youtu.be/nn-x44gB0oA

This is our helicopters journey this year.

Let me know if you have any questions!
Very very impressive. Did you guys find any modifications to the FFM kit to be helpful, or were you able to get a 3 minute time without modding the original plans?
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
Or...you can watch how much glue you put on your Heli when building.
"I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale." - Marie Curie

Enloe '19 || UNC Chapel Hill '23

See resources I helped create here!
Blonded
Member
Member
Posts: 16
Joined: March 12th, 2018, 1:01 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by Blonded »

daydreamer0023 wrote:
Blonded wrote:
Rêveur wrote:
Very very impressive. Did you guys find any modifications to the FFM kit to be helpful, or were you able to get a 3 minute time without modding the original plans?
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
Or...you can watch how much glue you put on your Heli when building.
10 drops of glue will weigh about 0.1 grams.
This is significant if you are not careful and definitely important to remember while building.

The CF Tow added to both spreaders weights about 0.25 grams which is much more significant.

It's hard to stress this enough but, all these things matter a lot and have to be considered to efficiently reduce your Chinook weight.
Blonded
Member
Member
Posts: 16
Joined: March 12th, 2018, 1:01 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by Blonded »

And I'd like to just add that the total weight of all the plastic pieces is 0.5 grams. It's likely you can get around 0.1 grams of weight of those pieces.
Rêveur
Member
Member
Posts: 47
Joined: December 26th, 2017, 10:45 pm
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by Rêveur »

Blonded wrote:
Rêveur wrote:
vjindal wrote:https://youtu.be/nn-x44gB0oA

This is our helicopters journey this year.

Let me know if you have any questions!
Very very impressive. Did you guys find any modifications to the FFM kit to be helpful, or were you able to get a 3 minute time without modding the original plans?
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
Thanks for all the help you guys!
Is not putting CF on the horizontal spreaders safe? Really don't want a near 3.0g helicopter that you spend so much time and effort into to snap right as you're trying to transfer the rubber from the winder to the helicopter
vjindal
Member
Member
Posts: 35
Joined: January 16th, 2016, 3:34 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by vjindal »

Rêveur wrote:
Blonded wrote:
Rêveur wrote:
Very very impressive. Did you guys find any modifications to the FFM kit to be helpful, or were you able to get a 3 minute time without modding the original plans?
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
Thanks for all the help you guys!
Is not putting CF on the horizontal spreaders safe? Really don't want a near 3.0g helicopter that you spend so much time and effort into to snap right as you're trying to transfer the rubber from the winder to the helicopter

We were able to get to 3.0g using 1k tow on the spreader bars. I can't speak to whether it was necessary (I never tried without), however I will say that our helicopter still was bending considerably even with the tow due to the torque of the rubber band.

A couple other things about weight: we realized there was quite a bit of variation in the weight of Ziggy's parts. I'd recommend weighing all the parts and picking the lightest. Some parts varied by almost .1g

We also cut the tips of the triangles that hold the carbon fiber together on the blades. This cuts about .06g
2019:
Mousetrap
Wright Stuff
Sounds

MIT 2018:
Heli: 1st
Mousetrap: 6th

--- Helicopters --- https://youtu.be/nn-x44gB0oA
--- Robot Arm --- https://www.youtube.com/watch?v=gmHcG-bar7w&t=76s
--- Wind Power --- https://www.youtube.com/watch?v=603F7vPUbrg&t=34s
sciencegirl03
Member
Member
Posts: 50
Joined: December 26th, 2017, 6:41 pm
Division: C
State: MI
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by sciencegirl03 »

vjindal wrote:
Rêveur wrote:
Blonded wrote:
Here are a few:
1. Don't put any CF Tow on the horizontal spreaders.
2. Sand down ribs as much as possible.
3. Sand down the edges on the plastic pieces (they weigh a lot more than you might expect).

This very quickly gets you closer to 3.0-3.1 grams.
Thanks for all the help you guys!
Is not putting CF on the horizontal spreaders safe? Really don't want a near 3.0g helicopter that you spend so much time and effort into to snap right as you're trying to transfer the rubber from the winder to the helicopter

We were able to get to 3.0g using 1k tow on the spreader bars. I can't speak to whether it was necessary (I never tried without), however I will say that our helicopter still was bending considerably even with the tow due to the torque of the rubber band.

A couple other things about weight: we realized there was quite a bit of variation in the weight of Ziggy's parts. I'd recommend weighing all the parts and picking the lightest. Some parts varied by almost .1g

We also cut the tips of the triangles that hold the carbon fiber together on the blades. This cuts about .06g
We tried with and without the tow on the spreader bars and it is definitely a gamble. They do bow and can break without the tow. Shaving off the plastic pieces is a good idea, just don't shave too much.
"Success is not final, failure is not fatal: it is the courage to continue that counts." - Winston Churchill

2019 Nationals:
Wright Stuff: 3rd
Protein Modeling: 4th
Geologic Mapping: 5th
sciencegirl03
Member
Member
Posts: 50
Joined: December 26th, 2017, 6:41 pm
Division: C
State: MI
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by sciencegirl03 »

vjindal wrote:https://youtu.be/nn-x44gB0oA

This is our helicopters journey this year.

Let me know if you have any questions!

Nice!!! You didn't make it to Nats?
"Success is not final, failure is not fatal: it is the courage to continue that counts." - Winston Churchill

2019 Nationals:
Wright Stuff: 3rd
Protein Modeling: 4th
Geologic Mapping: 5th
Blonded
Member
Member
Posts: 16
Joined: March 12th, 2018, 1:01 pm
Division: C
State: NY
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by Blonded »

sciencegirl03 wrote:
vjindal wrote:https://youtu.be/nn-x44gB0oA

This is our helicopters journey this year.

Let me know if you have any questions!

Nice!!! You didn't make it to Nats?
Ward Meville came in 3rd. It was very close.
https://www.ezratech.us/competition/new ... es/results
sciencegirl03
Member
Member
Posts: 50
Joined: December 26th, 2017, 6:41 pm
Division: C
State: MI
Has thanked: 0
Been thanked: 0

Re: Helicopters C

Post by sciencegirl03 »

Has anyone noticed sag in kevlar thread? For us, it is tight on the helicopter where we build/practice, but sags at different locations- like at different schools/invitationals. I'm guessing it is not the Balsa contracting, but the kevlar sagging. Any thoughts?
"Success is not final, failure is not fatal: it is the courage to continue that counts." - Winston Churchill

2019 Nationals:
Wright Stuff: 3rd
Protein Modeling: 4th
Geologic Mapping: 5th
Locked

Return to “Helicopters C”

Who is online

Users browsing this forum: No registered users and 3 guests