Kicked out.
Painfully accurate.
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Haha cheers guys. I only got sent a photo of it⌠does google translate work for photos? Are are you all proficient in Chinese?
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Yes! You can import a photo into Google translate.
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please double check my math for TBDD motor Kv calculation
ERPM: 40527.0
Pole Pair: 14
Volts: 47.2
Duty: 95.0%
(40527/(28 x 47.2 x 0.95)) = 56 Kv
Can I get monstrous torque out of 63 series motors reduced with 3:31 gear drive - and 6â pneumatics? 6374 wont fit but anything smaller will.
I was thinking if I limit my top speed to 20mph I could use a low over motor - day around 100kv. Would that give me tire spinning - dangerous amounts of starting torque?
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non sequitur -
has anyone disassembled a TBDD motor?
i have a motor that rattles more than the cells at multnomah county jail during @SeanHacker 's annual âHacker Holiday Hootenannyâ . The thing was a B* to get off the hanger (see what i did there) and iâm reluctant to apply force without experienced guidance
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if you tested in bldc and it has 14 magnets I get:
erpm 40527
40527erpm / 7erpm per rev (assuming 14 magnets) = 5789.5 rpm
47.2v bat
47.2v * .95 duty = 44.84v effective volts to the motor
5789.5rpm / 44.84v effective = 129kv
129.1 kv
if you tested in bldc and it has 28 magnets I get:
erpm 40527
40527erpm / 14erpm per rev (assuming 28 magnets) = 2894.7 rpm
47.2v bat
47.2v * .95 duty = 44.84v effective volts to the motor
2894.7 rpm / 44.84v effective = 64.5kv
64.5 kv
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thanks for the quick reply. yes i re-ran in BLDC after your comment last night.
so what i was missing was dividing the erpm by (7). thanks again
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itâs probably actually technically slightly higher because you have to turn the motor a bit faster than it will turn on itâs own because the no load speed (for measuring kv) is measured at 0 motor current
itâs the speed at which the back emf voltage equals the applied voltage so 0 motor current
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are you telling me that EMF is more than just a one-hit wonder from the early 90âs? the things you learn on the internetâŚ
thanks again!
Itâs 28.
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Hey guys! Chris here, just migrated from the other builders forum. Didnât have an account there but had been lurking on and off for the past year contemplating a diy build. I believe new users are not allowed to post new topics so I guess I shall direct my question to this newbie thread!
Just wondering - how do people place orders around here? I realise there are some people selling parts through this forum but I have no idea if they are trustworthy or not. Is there a tag on an individual for me to see if they are a trusted seller?
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Use Paypal and select âGoods and Servicesâ
This gives you recourse in case the person does not ship your goods. The seller also pays approximately a 3% fee from what you send them, for this insurance.
Donât use Paypal âFriends and Familyâ for anyone except friends and family, because itâs just like crisp cash banknotes in real life â once sent, itâs gone. However, no fees are paid by either party.
This is all assuming all transactions are within the USA borders. For international, there are other fees.
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Hey Chris-
I bumped your account so you can post and message. Itâs what I do around here.
Welcome!
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Hey thanks!
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It depends on the sales thread. Leave a comment on it and you transition into a pm for more details or just do the dm. Tell them what you want, you pay, give them your Adress and they ship it. Some sellers have a website which usually is listed within the Post itself.
Some topics about trusted sellers and trusted battery builders :
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Sorry if this is super noooob.
How do you calculate gearing like 3dsas does with 1: 3.5 or 1: 2.6?
I want to know how many teeth on each pulley because you canât add 1: 2.6 in an esk8 calculater.
Cheers
Just multiply everything by whatever (ten is easy) to get numbers the calculator likes. The numbers themselves donât matter, only the ratio. That way 1:2.6 = 10 and 26. You could also multiply by a hundred, or fifty, or fourty-two. Doesnât matter, as long as you do it to both sides.
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