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Looking for motor/esc advice

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Old 11-30-2013, 11:53 PM
  #1
FahrtAutoRC
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Default Looking for motor/esc advice

I'm an old hand when it comes to general bashers and racers, but this crawling stuff is new to me still, so, once again, here I am, asking questions like a noob!

In the morning I will be ordering the wife a WATERPROOF brushless system for her crawler. I am looking for advice on what the best one is to go with, not top-o-the-line expensive, but we have a modest budget for it. Here are our requirements:

She has a Losi 2.2 Comp crawler, with worm drive and DIG unit. She's running a FlySky FS-GT3b Tx/Rx, and hiTec titanium gear servo with a 2s 5400mAh 40c LiPo. I'm looking for decent speeds of about 8-12 mph, decent torque, and most importantly, waterproof.

Waterproof, speed and torque are what it needs as it will be used as a trail rig. I have already waterproofed everything else, but since having hassles with used equipment, I will be ordering it brand new for her. No more screwing around.

This is not a competition rig, it will be used for weekend runs with friends and likely nothing else.

Two options on my list have been the Turnigy Trackstar system and the waterproof Castle Sidewinder. Anyone have experience or a say on either of these?

One last thing: What is recommended Kv range?
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Old 12-01-2013, 01:36 AM
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All I can suggest is really think if sensorless is what u want, they don't have that smoothe transition from a standstill to driving. Like a brushed motor does because They have a minimum rpm.

This might be worth reading before u decide.
http://www.homebuiltrovs.com/rovforu...php?f=3&t=1139
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Old 12-01-2013, 09:54 AM
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So you're basically recommending sensored for crawling purposes because of the likely many low-RPM situations she will face? I really would like to keep things brushed but from what I've been told by many, that's not the best option. Still just looking for recommendations for waterproof BL setups for this thing.
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Old 12-01-2013, 05:36 PM
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Yep... Sensored or brushed

"...you do not already know, the motors need to be moving a bit before the ESC can sense the motor's position and know what phase and when to energise next. To get the motor moving, the ESC randomly energises a set of coils in the motor and looks for what comes out. Some ESCs will do this better than others at lower RPM's..."

Sensorless combos don't have that smoothe transition from a standstill to driving. Like a brushed motor does because They have a minimum rpm at witch the motor will rotate.

Example... With motors on a test bench...using made up fingers but it reflects whatn I'm talking about
say u apply 2% throttle to a brushed motor... It will buzz and most likely start turning very slowly
and if u bring the throttle up from 0-100% very slowly u will see it starts off at 0rpm and increased speed with the throttle input.

say u apply 2% throttle to a sensorless combo.... nothing happens... So u bring it up very slowly to 5% then all of a sudden the motor starts spinning at 2,000rpm....(depending on motors KV) And no matter what u can't get it to spin and slower... It's either that, higher or nothing

I guess ultimately sensored brushless would be better performance wise maby due to its torque curve.... But when u compare value for money... Brushed wins hands down..

Last edited by phmaximus; 12-01-2013 at 05:43 PM.
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Old 12-02-2013, 12:40 AM
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For an SCX10, you want a 18t pinion, a 35T motor and any ESC that can handle 35T brushed AND has a strong drag brake as well as instant reverse. You will set the ESC up to be instant forward/reverse and full drag brake, to hold on the rocks.

If you want a nice setup that isn't too expensive, get a Tekin FXR and a Holmes Hobbies Torquemaster 35T (smother than something that's very smooth that's just been polished extra smooth). I run this motor in my comp crawler and my SCX and it is 'amazing'. Bear in mind you need a strong servo too and ABSOLUTELY NEED a bec.

Don't go brushless. When the holmes motor wears out, send it back for a 20 buck rebuild and get it back like new.
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Old 12-02-2013, 12:48 AM
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Check out these ESC... Can beat the price... Cheapest I've seen with drag brake.... I'm currently using one and have ordered another...

what ya think?

http://www.ebay.com.au/itm/320A-7-2V...9ae3f82&_uhb=1
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Old 12-02-2013, 01:10 AM
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Id need to try it, the difference between a good and bad esc for crawling is how.many 'steps' it has in each direction and how.smoothly it can deliver small amounts of current. Holmes hobbies (.com) currently.has.a.sale.on.his.escs which are amongst the best in the biz.
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Old 12-02-2013, 05:14 PM
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I've been hearing that name a lot lately...

I dont think ive ever had a quality ESC so I've got nothing to compare it to lol...

Well all all I have is this video... Seems ok on 3s with dual 80t motors... But yeah, I've got nothing to compare to

http://youtu.be/ejOs-JI9VwM
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Old 12-02-2013, 06:54 PM
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Well, thanks, guys! I forgot I made this thread honestly, I was kind of panicked about getting the Losi right for her. Obviously with the G6 on its way I've given up on the Losi, and it's either getting sold or will become yet another of my "never ran shelf queens"! Those make nice bargaining chips for future trades! I've got my mind set on equipment and got everything ordered to show up with her G6 Jeep, and in my AX10 I'm happy with the XL5 ESC and old school Trinity P2K2 Pro motor powered by a 2s 40c LiPo, It's got TONS more power, speed and punch than the Tamiya silver can did (of course). If the truck will spin tires on carpet, I'm sure it's more than it really needs for casual trail runs, and since the P2K2 was my first upgrade to my first RC years and years ago, I can't get over the nostalgia of it! VERY happy guy here!

As for her G6, she's getting a brand new warrantied XL5, Axial 27t, and her 5200mah 40c 2s just arrived, and I already waterproofed a nice HiTec titanium gear servo for her, she should be more than happy with this combo.
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