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But with the tweeking comes a way to verify if tweeking has been done. By using a computer to plug into the speed control and "see" the software program. As simple as changing the profile in you KO speedo now. I like brusshless. It is all most unlimited HP.
 
Lots of good points here. Taking a step back, it sure seems like we are headed toward an F1 mentality that has been prevalent in 1/8th scale for years. Judging by 1/8th scale numbers, and the domination exemplified by the 2004 FIA season, is this really the direction we need to be taking things???
 
There will always be an advantage to having better batteries regardless of what motor you're using. The factory drivers will always get the better cells because they are factory drivers. Brushless won't make the battery war any worse. In fact, for the casual user it will make batteries less of an issue.

The current OEM's (mom and pops) will still buy motor "R" or "O" and wind the can to their specs. The two things that will hurt the small companies are longer lasting motors (we buy less) and the loss of consumable items like brushes and springs. These companies will have to start selling other consumable items to make up the differance.

With the current 8 turns (except the Orion) you're going to spend about $20 a race day on brushes. Even the Orion motors will use up a set of brushes in one day. The weekly brush savings is a huge improvement that can't be ignored.

BTW: The brushless motors (at least the Novak) use neodymium magnets and they won't demagnetize like the magnets in our brushed motors. When they say low maintenance, they really do mean it.
 
Discussion starter · #44 ·
DynoMoHum said:
One interesting thing I've heard a little about... Big Jim claims that brushed motors could be just as effcient and/or powerfull as a bushless motor if things such as exotic magnets and 5 segment armatures were used in them
And what would those cost? Look at current Colbat motors and they are priced at $200+, close the price of a full BL motor/ESC combo. Then you still have the consumables such as brushes and springs
 
now this is good...

ok, here's the thing.. ROAR sets guidelines for ROAR sanctioned events. ROAR does NOT mandate to manufacturers how to make their products. If the company wants to make a product for a racer to compete in ROAR events, they can and will do so. Basically, ROAR is about a standard set of rules and guidelines to mandate the running of ROAR events - not to dictate what YOU purchase.

Hank, the wheel thing was a good example. ROAR rules state what the wheel size can be to be considered legal in ROAR sanctioned events - which, that one, follows IFMAR policies for Worlds event participation. Proline had a situation with their molding process and it came to light with the new wheels about a year ago. ROAR allowed these wheels a 180 day grace period to allow Proline to retool the mold, for those who plan on competing in ROAR events. Coincidentally, Losi had the exact same issue with 4wd fronts.....

Brushless is here to stay. NOVAK DID NOT dictate the policies. There are 5 manufacturers following the basic set of guidelines we have established and will put into place for the next rule book. Again, these are basic guidelines that will be revamped as time goes on and technology increases and the needs and wants of the MEMBERSHIP requests it. :)

I hope I put some of the negative aspect of this new class into ROAR aside? Growth in the sport is what will keep it around.. not negating a new idea....
 
Some of the (proposed) Li-Poly solutions I've seen would put two or three cells in a parallel. Put a couple of those stacks in series and you've got something that produces 7.2V and can easily handle 30-40 amp draw. And the net weight would still be less than NiMH for the same capacity.

NiMH are still a great deal (from both a performance, reliability and price standpoint), so I don't see LiPoly storming into the land-based RC market any time soon.
 
Discussion starter · #48 ·
Some have said that some manufacturers present BL motors do not follow ROAR wiring standard with a comment that they are thinking of suing. We have to look at ROAR's recent history and how they have worked with manufacturers to help them become compliant. In the case stanted above, Pro-line was allowed a waver. We also know that GP was allowed a waver.

Why wouldn't these motor manufacturers approch ROAR asking for a waver instead of talking about suing. Maybe they could offer an adaptor that would convert their present wiring scheme to the ROAR standard with the understanding that new products will conform. I bet ROAR would be open to something like this... they are not here to hurt manufactuers and in fact have worked with them to help them make their current products usable at ROAR races.
 
LiPo cells are great for receiver cells and for smaller vehicles like mini T's but they can't source the current necesary for even stock racing at this time. Because of the high current spikes involved, the cells would heat up reducing their lifespan.


Has anyone seen what happens to a LiPo cell when it's dead shorted? It's pretty impressive. Just one of the reasons that they aren't a good option yet.

There are cells in the works that would actually handle the current but they're not LiPo and they're a couple of years out.
 
DynoMoHum said:
One interesting thing I've heard a little about... Big Jim claims that brushed motors could be just as effcient and/or powerfull as a bushless motor if things such as exotic magnets and 5 segment armatures were used in them...
With all due respect to Big Jim, the brushed motor has a commutator, which puts it at an inherent disadvantage. The brushes have resistance and friction, and the comm wears and gets out-of-round, none of which is present in a brushless.

I personally find it doubtful that Joe Racer (or even Joe Software Hacker Racer) is going to be able to reverse-engineer Novak's software (in machine code, NOT DOS) and re-write it to make it run better than the guys that designed it. Most of the "tweaking" that goes on with brushed motors is finding the right brush/spring combo and keeping the comm perfectly round. The only brushed motor variable that might apply to brushless is timing, but I suspect the manufacturers have already found the optimal timing point and ship them that way. The other big variable in brushed motors is the magnets & can they're in. Ceramic magnets aren't as consistant as the rare-earth ones used in brushless motors. As already mentioned, the neodymium magnets in the rotor aren't going to lose strength, so magnet zapping isn't an issue.

I've been running a Novak brushless since the outdoor season started (8-10 race days), and it hasn't lost any performance that I can detect. The only complaint anyone has had with them (there are 4-6 of us using them) is that when you over-gear them, the ESC shuts down due to overheating. If you wait 20-30 seconds, it cools off and you can keep racing. Compare this to a brushed mod motor. When you over-gear one of them, what could happen is:
A-You dump the battery
B-The brushes fry
C-The comm gets torn up
D-The windings fry
E-The magnets get hot & lose strength
F-Any combination of A through E

And here's some fun info for Glenn (a.k.a. DynoMoHum)
Code:
[font=Courier New]NOVAK SS5800 MOTOR SPECS (FROM NOVAK):[/font]
[font=Courier New]POWER RATING : 196 Watts[/font]
[font=Courier New]SPEED : 5800 RPM/Volt[/font]
[font=Courier New]TORQUE : 0.45 in-oz/Amp [/font]
[font=Courier New] [/font]
[font=Courier New]ACTUAL TURBO-DYNO NUMBERS AT 6.7 Volts:[/font]
[font=Courier New] RPM  TORQ WATTS EFF% AMPS[/font]
[font=Courier New]29767  3.6   80   80  14.9[/font]
[font=Courier New]27893  5.1  107   79  20.0[/font]
[font=Courier New]26406  6.6  130   77  24.8[/font]
[font=Courier New]25166  8.2  153   75  30.0[/font]
[font=Courier New]24106  9.5  170   72  24.9[/font]
[font=Courier New]23062 10.9  186   68  40.0[/font]
[font=Courier New]22244 12.1  199   65  45.0[/font]
Hey Hank, how come the columns don't line up anymore when you use the "code" tags??
 
??? I was wondering why the equally spaced text columns I used cut-and-paste with didn't line up after the paste. The "code" thing used to work when pasting from DOS or Notepad, but now it looks like space characters aren't the same size as normal letters.
 
I have enjoyed this hobby/sport since '88. As I age I am looking for more ways to make it more convenient to have fun. I am past the "I just gotta win" stage. Mind you I still really enjoy a good old 'Door to Door' race and have competed in many. Won some and lost some. To me the enjoyment is just being able to still pull the trigger. New inovations are cool, but the step from brushed to brushless is a giant leap forward. Many folks have wanted to and are telented enough to run modified but have been disappointed by the 'Maintenance' factor. "Gee I really want to run Mod but I don't have a lathe, can't solder too good, etc etc. Brushless opens up the opportunity of mod racing to many more people.
The most asked question I get from observers is. "How fast will it Go?", the next question is, "How much does it co$t", and "How much does it co$t to get started"? Then; What is all that stuff for on your work table for"? If you look at this from the standpoint of the person who is wanting to get started, the brushless system makes a lot of sense. Look what habppened when RTR vehicles first came out, we all said that It wouldn't do much for the hobby, and my LHS sells RTR 9 or 10 to 1. The point here is I think we need to adjust our thinking forward to what will increase the amount people involved in our hobby/sport. I know that I for one try to get more people involved at every opportunity.
 
In GR saturday the brushless guys where have problems with the unit overheating and turning off.It was hot out but the guy they where chasing had a brush motor he was faster and never had to stop for 30sec to cool down.The week before when it was cooler out the brushless was looking great I was think of geting one but now I dont know.A few of the guys had fans on the esc to and they still had problems .
 
Fred B said:
LiPo cells are great for receiver cells and for smaller vehicles like mini T's but they can't source the current necesary for even stock racing at this time. Because of the high current spikes involved, the cells would heat up reducing their lifespan.


Has anyone seen what happens to a LiPo cell when it's dead shorted? It's pretty impressive. Just one of the reasons that they aren't a good option yet.

There are cells in the works that would actually handle the current but they're not LiPo and they're a couple of years out.

I beg to differ, Lipo's can be extremely powerful and will last up to 45 min.s with a Brushless motor. Yes, they can explode or catch fire, but eventually that will be resolved.
Lipo's and Brushless are the future of electric racing. They would make electric much more desirable than nitro. If someone can go just as fast, w/ No maintance, and run just as long, what keeps them away from electric racing?

We all know it's coming, and sometime we'll have to give up our lathes, dynos, serrators, ect... but it will be in best interest of the hobby.
 
What about Lithium Ion rather than Lithium Polymer?

I have had some experience with them in 1/18 scale. They were 2 cells and i believe had a 7.2v output. They were extremely light as well. They also had a problem with exploding into flames and burning down houses, but it was very rare, and the people it happenned to were probably using a NiMH charger rather than a charger designed to charg L-Ion cells.
 
Like I said, LiPo batteries aren't there yet. That doesn't mean that they aren't going to improve. There are new chemistries and new constructions in the works that will make this type of cell viable for RC but they're years off.

Here are the three problems with LiPo cells currently:

1) A relatively high internal resistance means that the cells can't source the 100 amp spikes that mod racing puts on the cells (70 amps in stock) unless you use 3-4 packs in parallel.

2) High current draws and heat greatly reduce the life of LiPo cells. Not that the current GP's last forever but who knows how long these things will last at an average of 30-40 amps. The plane guys don't see the huge spikes that we do so this is less of an issue with them

3) The risk of fire after a crash is the one thing that will keep these cells out of the RC market. It only takes one person getting burned to kill these cells in RC. It's pretty easy for us to say that it's the user's fault for bad wireing but the insurance companies don't see it that way.



So, yes, new cell technology will make it's way into RC but not for quite some time. The LiPo cells are great and can be used in lower current draw stuff like receiver packs and MiniT's. But no, they aren't ready for 5 turn Orion motors yet.

Brushless motors may be better suited for LiPo but who knows...
 
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