Brushless Help (Calling Motor/ESC Gods!)

[All Out Racing]

I've been diggin' through all the threads on brushless setups, including the definitive threads and I am still lost. From what I've gathered the brushless motors need to be in the 900-1200 rpm range, speedo needs to handle about 25-30 amps, and the shaft needs to be 1/8 inch just to make life easy. Now, what I don't get is if the RPM is directly related to the input voltage in what I think are KVs, woudln't 7.2 volts produce about 7000 RPM? Also, I've checked on the Novak systems, most of them say they are rated at 540 amps, how in the world is that possible with 14 gauge wire and plastic connectors? Is there really that big of a difference between name brand & off brand components? I've been all over ebay looking at brushless stuff, and there are hundereds (about 900 tonight) of motors and controllers and most of them are not names I've heard of. If the specs are the same ie: 25-30 amps, 6-12 Volts input, 5 volt 2 amp BEC will they not work just as well as the more expensive units? Finally, how in the world do you program the off brand units, or can you? Thanks in advance for the fog-lifting clarifications...

[All Out Racing]

Well, due to the overwhelming response to my question, I've decided to just put off the brushless setup until I can learn more about them. Looks like it'll be a lathe and Rooster setup for my rig...

[cartronicshn]

you should pm maybe johnrob holmes he might be able to help you out, www.holmeshobbies.com

[EeePee]

Since you're using name brand brushed stuff, why not use name brand brushless stuff and not worry about it?

[JohnRobHolmes]

I can simplify things a bit for you.

First off, it can take a day or two to get an answer around here or on any forum for that matter. 5 hours isnt that much time to wait!


If you are willing to do some work, your options on a motor are almost limitless. A very easy rule of thumb I use is that TLT's need at least 2 oz of outrunner, and unlimited scale rigs like to have 4oz or more, preferably 6oz. The outrunner should have at least 8 stator teeth, 12 stator teeth being preferable. From this point each motor will have its own shaft size and mounting pattern for you to deal with. There is no standard for an outrunner.

If you want a more definitive answer and you dont want to have odd pinions/ odd motor mount issues, your choice on an outrunner is boiled down to THREE companies right now. MPjet, AXI, and my own Revolver motors are the only ones I am aware of with 25mm bolt pattern compatible with our "540" motor mounts. MPjet has 5mm shafts on the motors that work, AXI has many differnt shafts including 3.2mm, and my motors have a 3.2mm shaft.


ESC's:
I assume you are in the states, So your choices for an available brushless sensorless esc are very limited. Castle creations and Quark are your best options. Mtroniks is out there too, but I have not read many good reviews of the brushless controllers. Yes, you can get other brands. MOST of the stuff you see on the internet is for a plane or heli and it will not work. For a ground based vehicle you wont find a new ESC under $80. Try to get warrenty work on other brands (in the U.S.) and you will see why I say you have two major brand choices. At the moment the Castle mamba 25, mamba maxx and the Quark 33 are most popular and easily available controllers for a crawler.


The other option that is in a class of its own is the Novak systems. They are sensored, and they work well from what I have seen. There is a crawler system being released right now, but the SS systems would work too.


Clear as mud? There is a lot to consider, and you didnt specify what vehicle you are putting it into.

[All Out Racing]

It was in the wee hours 1:24 AM when I posted, but I know I am not very patient. The crawler I'd like to put the brushless system in will be TLT based, and comperably heavier than most rigs. I am not as concerned as most with the RPM level, as the tranny I have planned has a wide range of final gear options. What I still don't understand is the difference between the plane/heli brushless and cars/crawlers/land based. Are the timing frequencies different, or the power curve setups? Would a Hacker system be worth looking into for a crawler, or are they too fast for a low speed vehicle? Also, is there any way to waterproof the brushless ESCs, or do they need to remain somewhat open for heat reasons? Thanks again for everyone's help

[Reflection]

Originally Posted by All Out Racing

It was in the wee hours 1:24 AM when I posted, but I know I am not very patient.

Patience is a virtue. Even if you get one quick responce on something your not sure of.....how do you know that guy ain't blowin smoke. It's better to get several opinions,makes it easier to understand and you can make a better choice for your set up. What works for one won't work for the next,if you know what I mean.

Originally Posted by All Out Racing

What I still don't understand is the difference between the plane/heli brushless and cars/crawlers/land based.

Reverse is a WONDERFUL thing,especially on a crawler,heck I probly spend as much time or more in reverse as I do foward. Some ESC's are foward only,some are foward/reverse and then some are even programmable as to how much foward and how much reverse. When I make an obsticle in foward,sometimes it's fun to,and sometimes alot more challenging,to turn around and try it backwards.

If you can't tell from my sig line,JohnRobHolmes is the man when it comes to electronics. He's done ALOT of trial an error and has a plethera of knowledge about how to move a crawler with axle twisting power. He's helped me alot with info,awesome prices and great customer service.

I'm currently running a Mamba Maxx and a MPJet brushless motor. You can see my set up by clicking HERE . The ESC in those pics is the Mamba 25. I tried it first and it worked great. It wasn't quite stout enough for the weight of my rig and the size of my BIG tires I run at times(8 1/2" LST/Kongs). The only thing it would do was thermal shutdown once in a while,other than that....it worked awesome. I didn't wanna risk burning it up so I upgraded to the Mamba Maxx. This ESC is ALOT happier in a big truck. For the 2.2 sized rigs,I feel the Mamba 25 is perfect. For a super sized rig,no question,this Mamba Maxx is AWESOME. As of right now,I wouldn't even concider another set up. I took JRH's advice and it works awesome.

[JohnRobHolmes]

To your Q about a hacker system, almost all non sensored inrunners do not work for crawlers, but the outrunners would work. I have tried 2 and 4 pole inrunners and they wont start up with a bound tire. An 8 pole inrunner might work, but they are generally huge motors that ouput a few horsepower.

FYI Quark is Hacker

[S-Dog]

JRH is my electronics HERO!!!!!!!!!

[S-Dog]

I personally went with the mamba25 and revoler... I can't wait till my motor comes in!!!! ITS IN!!! Yahooooo