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Old 05-28-2007, 12:24 PM   #76
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now im not apart of the bl wagaon yet, well not like the novak sensored stuff..... but i want to ask, i have heard that those novak bl motors die with in a month of racing, now how far to a extent is that true? i mean i heat and all that, or do they just die from being ran?

my mamba max runs like a mad ape, and stills runs like day one! hasnt seen temps above 150 on the speedo and motor tho
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Old 05-28-2007, 12:32 PM   #77
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@V12

That is exactly why brushed speedos are far more efficient than brushless, and it gets worse as we use lower and lower turns motors as the switching speed in the speedo increases with the motor revvs. So we agree that brushed speedos are far more efficient due to the very design of both technologies and this won't change.

Re 3.5T, I believe 99% of the top 40 of the BRCA nationals use a 3.5T. They are easily driveable too, but runtime is an issue. However 1 driver showed that a 4.5T can be just as quick by putting it in the A. Kudos to Elliott Harper I bet you'll see this kid's name in A finals in international races soon, he's getting that good.
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Old 05-28-2007, 12:44 PM   #78
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Quote:
Originally Posted by BlackedOutREVO
now im not apart of the bl wagaon yet, well not like the novak sensored stuff..... but i want to ask, i have heard that those novak bl motors die with in a month of racing, now how far to a extent is that true? i mean i heat and all that, or do they just die from being ran?...
The early Velociti motors had bonded rotors that do not hold up as well as the newer sintered magnets. Late last year, Novak replaced the bonded rotors and upgraded the Velocitii series motors with sintered rotors.

Most of the older motors didn't actually "die"---many were revived with the installation of the sintered rotor by the user.
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Old 05-28-2007, 12:47 PM   #79
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This thread is a cripple fight.
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Old 05-28-2007, 01:48 PM   #80
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Quote:
Originally Posted by NovakTwo
Teching brushless motors is neither difficult nor complicated. TeamNovak has posted teching instructions on their website for a couple of years. The chart has recently been updated with instructions for teching motors with the rotors removed.
This is always the answer from those people who never organise a race, or do tech.

What you are saying is that every motor must be opened, have the rotor removed, and then have the stator checked with a meter. How long do you think that is going to be accepted by drivers who need their cars back for prep, and tech inspectors who spend their whole day taking motors out and dismantling them? Imagine having to do this for 100 drivers at a meeting, sealing them, then dealing with all the queries, or teching their spare motors, etc.

On a brushed, simply look at the armature ends, peer into the can slots for the label, check the brushgear, and the job's done.

Take it from me, teching a brushless motor is nothing like as easy as it looks. For anyone who doubts that, remember all the effort we put into checking 12T motors...

As for the efficiency issue, it's a no-brainer. BL has no friction losses, rare-earth magnets, and additional sensors for keeping an eye on the timing - BL will kill BD every time. Until we get the BD rare-earth magnets...
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Old 05-28-2007, 02:10 PM   #81
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Quote:
Originally Posted by NovakTwo
The early Velociti motors had bonded rotors that do not hold up as well as the newer sintered magnets. Late last year, Novak replaced the bonded rotors and upgraded the Velocitii series motors with sintered rotors.

Most of the older motors didn't actually "die"---many were revived with the installation of the sintered rotor by the user.

well how long do the sintered ones last? once a year, month, what?

and why does everyone call them special earth mags? there neo mags arent they?
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Old 05-28-2007, 02:15 PM   #82
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slower one , you need to learn how to tech a brushless...
Look for how on TeamNovak.com.....

Its not hard to do at all , even easier to inspect than a brush design....
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Old 05-28-2007, 02:15 PM   #83
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Quote:
Originally Posted by SlowerOne
What you are saying is that every motor must be opened, have the rotor removed, and then have the stator checked with a meter. How long do you think that is going to be accepted by drivers who need their cars back for prep, and tech inspectors who spend their whole day taking motors out and dismantling them? Imagine having to do this for 100 drivers at a meeting, sealing them, then dealing with all the queries, or teching their spare motors, etc...
No, Novak does not say that "every motor must be opened". It says "For the highest possible accuracy in testing your motor for compliance, we recommend removing the rotor prior to testing the motor phases."

Most teching can easily be done without disassembling the motor. At regional and national races, teching the disassembled motors of the winners should be adequate. Knowing that the motors can undergo this level of testing at any time should eliminate the desire to cheat.

Race directors can institute any level of testing of BL motors with which they are comfortable.
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Old 05-28-2007, 02:18 PM   #84
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The brushed holdout crowd is getting desperate. Look at what you guys are left with, and clinging to? I'm embarrassed for you.
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Old 05-28-2007, 02:32 PM   #85
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Quote:
Originally Posted by SlowerOne
On a brushed, simply look at the armature ends, peer into the can slots for the label, check the brushgear, and the job's done.
Oh yea... with that tech procedure there could be NO cheating
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Old 05-28-2007, 02:32 PM   #86
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Quote:
Originally Posted by BlackedOutREVO
well how long do the sintered ones last? once a year, month, what?

and why does everyone call them special earth mags? there neo mags arent they?
If you run motors with the sintered rotors within spec and with the appropriate gearing, the rotors should not require replacement. The Novak motors are thermally protected when used with a Novak esc.

Novak doesn't use the term "rare earth magnets". But here are descriptions of rotor materials:

Sintered Rotors: Sintered magnets are a type of ceramic composed of compressed Neodymium-Iron-Boron powder. Sintering involves the compaction of fine alloy powder in a die, and then fusing the powder into a solid material with heat. While the sintered magnets are solid, their physical properties are more similar to a ceramic, and are easily broken and chipped. Sintered NdFeB magnets are generally plated or coated with Nickel-Copper-Nickel plating to prevent corrosion. Nickel-Copper-Nickel plating has excellent corrosion resistance and durability as well as providing a clean and shiny appearance. Magnets used in Novak motors are high-energy 30 MGOe, and high temperature materials.

Bonded Rotors: A recent development in magnetic materials is the high-energy polymer bonded magnet. Magnetic powder, namely neodymium-iron-boron (NdFeB), is blended with polymer and injection molded to form complex shapes. A maximum magnetic energy level of 12 MGOe is attainable with bonded magnets. The biggest shortcoming of bonded magnets is the low operating temperatures.
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Old 05-28-2007, 02:38 PM   #87
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Quote:
Originally Posted by BlackedOutREVO
now im not apart of the bl wagaon yet, well not like the novak sensored stuff..... but i want to ask, i have heard that those novak bl motors die with in a month of racing, now how far to a extent is that true? i mean i heat and all that, or do they just die from being ran?

my mamba max runs like a mad ape, and stills runs like day one! hasnt seen temps above 150 on the speedo and motor tho
Thanks to the sintered rotor its not uncommon to see one last for a year or even longer. As long as you don't over heat it dramatically it would possibly last years, and I'm speaking from a lot of hands on testing.
I just ran a 20 minute main in off road truck, and I ran it against 1/10th gas trucks. In a 20 minute main with 6000 mah batteries and a GTB 4300 I ran 20 consistent minutes with no power loss and had voltage to spare, the motor came off 129 degrees. And the speedo was 99, the outside temp was about 75 to 80 degrees. Oh and I won the race.
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Old 05-28-2007, 02:41 PM   #88
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Quote:
Originally Posted by NovakTwo
If you run motors with the sintered rotors within spec and with the appropriate gearing, the rotors should not require replacement. The Novak motors are thermally protected when used with a Novak esc.

Novak doesn't use the term "rare earth magnets". But here are descriptions of rotor materials:

Sintered Rotors: Sintered magnets are a type of ceramic composed of compressed Neodymium-Iron-Boron powder. Sintering involves the compaction of fine alloy powder in a die, and then fusing the powder into a solid material with heat. While the sintered magnets are solid, their physical properties are more similar to a ceramic, and are easily broken and chipped. Sintered NdFeB magnets are generally plated or coated with Nickel-Copper-Nickel plating to prevent corrosion. Nickel-Copper-Nickel plating has excellent corrosion resistance and durability as well as providing a clean and shiny appearance. Magnets used in Novak motors are high-energy 30 MGOe, and high temperature materials.

Bonded Rotors: A recent development in magnetic materials is the high-energy polymer bonded magnet. Magnetic powder, namely neodymium-iron-boron (NdFeB), is blended with polymer and injection molded to form complex shapes. A maximum magnetic energy level of 12 MGOe is attainable with bonded magnets. The biggest shortcoming of bonded magnets is the low operating temperatures.
They are Neodynium magnets and so they are rare earth magnets. Sintered or Bonded only refers to the manufacturing process which is what you have described.
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Old 05-28-2007, 02:47 PM   #89
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Quote:
Originally Posted by syndr0me
The brushed holdout crowd is getting desperate. Look at what you guys are left with, and clinging to? I'm embarrassed for you.
Desperate for what ? There is no comparison with the smoothness of a brushed motor and this is it's main advantage. In boats and planes it doesn't matter how smooth a motor is as they are using a propeller. Brushless is much better at constant load than it is in a transitional mode.

For planes and boats you are applying a constant load most of the time whereas for cars we are always in transitional mode apart from the last part of the straight.

It would be nice to see both technologies on par that's what I say, so the user can choose what's best for him. A lot of people thought when brushless motors were first intriduced in the industry, that brushed were on their way out. Well I've got news for you, a lot of companies have gone to brushless and gone back to brushed. It's all about how you use them.

PS: I love the 5-cell mod class with b/l, having a lot of fun there so here's for me being a brushed lover.

PS2 : can't wait for the R1 to be released !
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Old 05-28-2007, 02:54 PM   #90
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Quote:
Originally Posted by TRF415boy
They are Neodynium magnets and so they are rare earth magnets. Sintered or Bonded only refers to the manufacturing process which is what you have described.
I said that Novak does not use the "term" rare earth magnets; I did not say that Novak does not "use" neodymium in the magnet material. I do understand the distinction.
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