Lightest Gearbox for Turnigy 80-100-B?

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socalfusions   10 mW

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Lightest Gearbox for Turnigy 80-100-B?

Post by socalfusions » May 12 2012 10:38pm

What is the lightest 25:1 gearbox, or variable ratio gearboxe, that is a good choice with the Turnigy 80-100-B?

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sn0wchyld   1 MW

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by sn0wchyld » May 13 2012 9:40am

socalfusions wrote:What is the lightest 25:1 gearbox, or variable ratio gearboxe, that is a good choice with the Turnigy 80-100-B?

is there a reason you're looking for 25:1? Because if you're trying to do all you're reduction in 1 stage you need to be aware that a box to handle a 80100 will be at least 100mm long... probably more. add that to the ~100mm of the 80100 and you've got 200++mm of stuff to mount to your bike. that's getting kinda wide. and then you still have to line up a chain with you're bike... if its for a BB drive then its going to be near impossible to mount it in a way that'll line it up with your chainring, and if its for a direct drive to the rear wheel then you dont need 25:1 in a box since you'll be able to have more reduction with the gearbox-wheel stage.

If you're not attaching the box directly to the motor's shaft, then there's little point in doing all your reduction in the box alone, since you'll typically need a chain or belt to go from the motor to the box, and another chain/belt to go from the box to you're cranks (I assume you're doing a BB drive given the 25:1 ratio). You may as well use the 2 chain/belt stages to gain some reduction, that'll let you use a smaller + lighter gearbox, say around 3-8:1.

Though ive yet to put mine to use, I'd suggest looking on ebay for PLE80's. They have a 100nm output continuous rating, and 14krpm input if I remember correctly. should be more than enough for the 80100. I've got a 5:1. Ill be doing roughly 2:1 for the first stage (motor to gearbox) and 3:1 for the last stage (box to BB) for a total of 30:1. you can see some pics in the link in my sig.

socalfusions   10 mW

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by socalfusions » May 13 2012 4:31pm

sn0wchyld wrote:
socalfusions wrote:What is the lightest 25:1 gearbox, or variable ratio gearboxe, that is a good choice with the Turnigy 80-100-B?

is there a reason you're looking for 25:1? Because if you're trying to do all you're reduction in 1 stage you need to be aware that a box to handle a 80100 will be at least 100mm long... probably more. add that to the ~100mm of the 80100 and you've got 200++mm of stuff to mount to your bike. that's getting kinda wide. and then you still have to line up a chain with you're bike... if its for a BB drive then its going to be near impossible to mount it in a way that'll line it up with your chainring, and if its for a direct drive to the rear wheel then you dont need 25:1 in a box since you'll be able to have more reduction with the gearbox-wheel stage.

If you're not attaching the box directly to the motor's shaft, then there's little point in doing all your reduction in the box alone, since you'll typically need a chain or belt to go from the motor to the box, and another chain/belt to go from the box to you're cranks (I assume you're doing a BB drive given the 25:1 ratio). You may as well use the 2 chain/belt stages to gain some reduction, that'll let you use a smaller + lighter gearbox, say around 3-8:1.

Though ive yet to put mine to use, I'd suggest looking on ebay for PLE80's. They have a 100nm output continuous rating, and 14krpm input if I remember correctly. should be more than enough for the 80100. I've got a 5:1. Ill be doing roughly 2:1 for the first stage (motor to gearbox) and 3:1 for the last stage (box to BB) for a total of 30:1. you can see some pics in the link in my sig.
25:1 isn't set in stone but is more of a general ratio I'm thinking around, I must state that although my project won't actually be an ebike but will incorporate similar mechanisms for the 80100 setup bikes.
Mounting space will be on a 3ft x 1ft piece of aluminum so their will be plenty of room. Can you elbaorate on the second method you were explaining which consisted of the 2 chain/belt stage? I was looking up the PLE80 in someones ebike build and it seems quite heavy at around 20+ lbs, what kind of smaller + lighter gearbox did you have in mind if I were to do a belt to chain primary reduction setup?

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by sn0wchyld » May 13 2012 7:25pm

socalfusions wrote:
sn0wchyld wrote:
socalfusions wrote:What is the lightest 25:1 gearbox, or variable ratio gearboxe, that is a good choice with the Turnigy 80-100-B?

is there a reason you're looking for 25:1? Because if you're trying to do all you're reduction in 1 stage you need to be aware that a box to handle a 80100 will be at least 100mm long... probably more. add that to the ~100mm of the 80100 and you've got 200++mm of stuff to mount to your bike. that's getting kinda wide. and then you still have to line up a chain with you're bike... if its for a BB drive then its going to be near impossible to mount it in a way that'll line it up with your chainring, and if its for a direct drive to the rear wheel then you dont need 25:1 in a box since you'll be able to have more reduction with the gearbox-wheel stage.

If you're not attaching the box directly to the motor's shaft, then there's little point in doing all your reduction in the box alone, since you'll typically need a chain or belt to go from the motor to the box, and another chain/belt to go from the box to you're cranks (I assume you're doing a BB drive given the 25:1 ratio). You may as well use the 2 chain/belt stages to gain some reduction, that'll let you use a smaller + lighter gearbox, say around 3-8:1.

Though ive yet to put mine to use, I'd suggest looking on ebay for PLE80's. They have a 100nm output continuous rating, and 14krpm input if I remember correctly. should be more than enough for the 80100. I've got a 5:1. Ill be doing roughly 2:1 for the first stage (motor to gearbox) and 3:1 for the last stage (box to BB) for a total of 30:1. you can see some pics in the link in my sig.
25:1 isn't set in stone but is more of a general ratio I'm thinking around, I must state that although my project won't actually be an ebike but will incorporate similar mechanisms for the 80100 setup bikes.
Mounting space will be on a 3ft x 1ft piece of aluminum so their will be plenty of room. Can you elbaorate on the second method you were explaining which consisted of the 2 chain/belt stage? I was looking up the PLE80 in someones ebike build and it seems quite heavy at around 20+ lbs, what kind of smaller + lighter gearbox did you have in mind if I were to do a belt to chain primary reduction setup?


you need to knock a 0 off that weight (well, almost). a single stage ple80 is about 2kg, or about 4lb. extra stages add about 400g. There isnt going to be anything much lighter than that that will handle the 80100's torque. at 25:1 even the ple80 isnt enough, as a 80100 has a peak torque of ~10nm, with a 25:1 box thats 250nm (the ple is rated at 110nm output). hence why you should use the reduction from you're output shaft to your wheel to get part of that 25:1. if you use a 3:1 on your final stage, then you only need a 8:1 gearbox, which means it'll only have to handle 80nm, rather than 250.

if you want a better idea of the 2nd method check the link to the d8 build in my sig. there's some pics of that exact setup - the chains on p5.

heres a spec sheet on the ple's
http://www.neugartusa.com/Produkte/E-cat-08.pdf

Tell us more about how you want to use it, its kinda hard to give advice without knowing its intended purpose.

socalfusions   10 mW

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by socalfusions » May 13 2012 9:02pm

you need to knock a 0 off that weight (well, almost). a single stage ple80 is about 2kg, or about 4lb. extra stages add about 400g. There isnt going to be anything much lighter than that that will handle the 80100's torque. at 25:1 even the ple80 isnt enough, as a 80100 has a peak torque of ~10nm, with a 25:1 box thats 250nm (the ple is rated at 110nm output). hence why you should use the reduction from you're output shaft to your wheel to get part of that 25:1. if you use a 3:1 on your final stage, then you only need a 8:1 gearbox, which means it'll only have to handle 80nm, rather than 250.

if you want a better idea of the 2nd method check the link to the d8 build in my sig. there's some pics of that exact setup - the chains on p5.

heres a spec sheet on the ple's
http://www.neugartusa.com/Produkte/E-cat-08.pdf

Tell us more about how you want to use it, its kinda hard to give advice without knowing its intended purpose.
2 pounds sounds much more reasonable, I must have misread that in another thread. I plan on using it in a large ornithopter setup with belts + pulleys for the primary reduction stage and chains + sprockets for the final drive. The setup of these components will be similar to ones used in modern ornithopters as shown in the video and picture below. Can the reduction method you stated above be applied to a configuration such as this?



Image

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E-racer   1 kW

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by E-racer » May 14 2012 4:23pm

the thought of an 80-100 powered ornithopter is frightening but i love it! good luck with your build!
Kona Stinky: custom swing arm w/ batteries
-13s3p Turnigy Li-po
-Turnigy 80-100 rewound 130kv (Burtie's optical board)
-Kelly KBL 48201
-Nuvinci Dev Kit
http://endless-sphere.com/forums/viewto ... 28&t=35341

Goped ESR750
-12s2p Turnigy Li-po
-Turnigy 80-100 HXT w/halls
-Kelly KBL 48201
http://endless-sphere.com/forums/viewto ... 35&t=20732

socalfusions   10 mW

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Re: Lightest Gearbox for Turnigy 80-100-B?

Post by socalfusions » May 14 2012 5:10pm

E-racer wrote:the thought of an 80-100 powered ornithopter is frightening but i love it! good luck with your build!
Gratitude good sir 8)

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